This video was a refresher for me. I surprised myself at how much I remembered threats to external and internal validity from undergrad. I liked how Dr. Grande did not just list what was a threat to each, but broke down each threat so that it was viewer friendly. Definitely helpful!
Danielle Maldonado I also liked how Dr. Grande broke down and explained each threat for internal; and external validity. It helped me understand what to be on the look out for when I check the validity of a study. However, this was not a refresher video for me, but rather an entire new look on validity. I do not remember going over the threats in undergrad, but I have a greater understanding due to this video.
This video had so much information packed into it about the threats to validity in research. There are so many different things that can affect the validity, then to add on participants interacting together, it's a lot to keep in mind. The explanation of the ecological threats was very helpful.
Dr. Grande- This information proven to give me understanding internal and external validity. This information allowed me to think back to my course in undergrad which allowed me to process the differences. It is important to keep in mind, that we must keep the experimental groups separate or the scores would not be accurate. Thank you!
There are so many things that can threaten the validity of your research. I'm glad that he talked about them in detail to help avoid error and so that we would know if we are using the process when analyzing the research.
Thank you for the comprehensive treatment of this subject. The list of possible ways for an experiment to lose validity surprised me, especially the list of threats to external validity. I expected the generalization problem, but many of the other issues, such as the novelty effect, were new to me.
Dr. Grande, This video has some great examples of the different types of internal and external threats. Your examples really helped me understand some of the harder to understand types. This video showed me how difficult it is to keep your research valid, especially with school age children due to their maturation.
This video is extremely helpful to me, as after reviewing all the threats to external and internal validity of an experimental research, I realized how careful and cautious researchers have to be to make sure of validity of a study. I like that you also provided ways to prevent or improve the threats to validity. However, I need to review this very often in order to apply these concepts and cautions into practice.
I learned so much about the types of threats to internal and external validity. I would always be confused when reading research articles because I did not understand the correct definitions of mortality or deception in a study. I now understand that mortality refers to participants dropping out of a study, and deception can be used to avoid demand characteristics. This video will help me when reading future articles and in designing my own research experiment.
It is very important to know how to recognize the validity of data found during the design portion of your research. Knowing and understanding internal and external validity will prevent making mistakes early on in the research process. Providing examples in laymen's terms was very helpful as well.
The video helped me to understand how important it is to be aware of all of the possible threats to both internal and external validity when conducting research experiments.
Thank you for this refresher on validity, there are many factors to consider when conducting research in a manner that protects validity. It seems that many of these would be accidental or easy to overlook. A good reminder in this video is the value of a double-blind experiment to remove inadvertent biases by the experimenters.
This video helped me realize how detailed an experiment can be with all of the threats to internal and external validity. Just one threat can change the outcome of an experiment. It seems as if there is just as much attention to the preparation of a research as the conducting of a research. Once again, the examples help paint a pretty vivid "big picture" for me.
Thank you for sharing this video Dr. Grande. There are many factors that can manipulate the study, but the two that caught my attention was the contamination and compensatory behaviors factors. It's eye-opening to hear the participants can manipulate the results by knowing what the other groups are being tested for.
This video made me realize how important it is to be aware and be mindful to potential risk factors that could jeopardize your research. It could happen at any step of the process, not just during analyzing data step.
This was a nice refresher course for me in internal and external validity. Unlike some of the other topics that are covered in Dr. Grande's videos I (surprisingly) have heard of internal and external validity from past research classes. However, these classes happened long ago and I have since forgotten quite a bit about them. What I found most interesting about this video was the population validity threat to external validity. This reminded me of a quote about going to the ocean, taking a cup of water, seeing that there is no fish in the cup, and therefore deducing that there are no fish in the ocean. While this is an extreme example I believe that that same thought process can sometimes happen in studies.
I appreciated the second scenario for statistical regression. Dr. Grande provided an example of the possibility of scores moving towards the mean when they are measured multiple times. At first this did not make sense to me, but as he further explained how the changes in scores could be perceived as benefits from the treatment, I was able to better understand this concept. Thank you!
This material is slowly, but surely starting to come back to me. I have heard about several of the threats to internal validity (e.g., experimenter bias, confounding variables). However, I will say that I don't recall learning about ecological validity or population validity. I suppose that we all learn something new every day! While some of the threats to internal/external validity probably can't be avoided completely, it's important that researchers stay aware of these threats so that they can reduce them as much as possible.
I found this video very clarifying in order not to make mistakes that may end up compromising the validity of a research. Being careful at the time of the design of a research not only would save a lot of time but also would assure us an accurate result
It was definitely great to be reminded of all of the threats to internal validity; I had forgotten about all of them! Contamination was one threat to internal validity that I had not thought about that would have a major impact on differences between various treatment groups. For amateur researchers, they may not be as strict about keeping their participants separate when waiting to participate in their study, or when they are leaving, which could adversely effect any post-participation results. I also had not thought about just how important it is to be wary of having experimenter bias. Since we may have an obvious vested in our research, it is advantageous to have a double-blind experiment so that we are not tempted to report only what we want to report or neglect to see important indicators that may pop up that experimenter bias may make convoluted.
This video did a great job explaining the importance of internal and external validity. Something as simple as selecting a sample that is not truly random can throw off results. Confounding variables were always a mystery to me in undergrad.
The pretest and posttest concept was new to me, even after having done research, both clinical and experimental, in undergrad. The safer the hypothesis' route of testing, the better--and more efficient for the PI and RAs!
The specific and realistic examples are very helpful in understanding the different concepts associated with internal and external validity, especially as there are so many things that could affect a study's validity. I also found it helpful that common threats to internal validity were pointed out. I found it useful that tips were given such as it being better to select instrumentation measures before the experiment and continue to use the same ones to preserve the internal validity of the study. As before, pointing out similar or interchangeable concepts such as attrition and mortality eases confusion. I would be interested to learn about the best ways to account for the most common threats to internal and external validity.
By watching this video, I was reminded how many different threats to internal and external validity there is. When the video talked about population validity, it got me thinking about how much a person really does have to consider when they do a research study. By considering the population sample, if one thing is wrong with it, it could throw your whole study off, which is something that needs to be fully considered and remembered when conducting a study. Also, when mentioned how sensitive results can be and how time can be a factor, I realized that validity is important in studies especially with things such as technology, because it is always changing, so the results may not always be valid for that time period, or even applicable.
This overview brought back memories of my Experimental Psychology classes in undergrad. I really appreciated the real life examples provided which made it much more memorable.
It was interesting too see all of the internal and external influences to validity. It really got me to thinking about all of the threats to validity that are possibilities during an experiment. There is no fire proof way to ensure an experiment will not be compromised but this video shared a nice list of threats (internal and external) to look out for. I really enjoyed this video.
This was an informational video which makes me aware of the need for understanding validity and flaws in validity whether translating psychology or in creating new studies for future development. I know this has been touched on in other classes, but this really gives me what I feel is a well rounded view of potential issues which may give studies false results (in both positive and negative ways). I am looking forward to trying to be more cognizant of potential risk factors which are posed as I read future studies and deal with the author's/authors' conclusion(s).
There are some many different ways that a study can be influenced. It is completely important to keep awareness to all the risk factors that can influence a study in order for the validity to be as close to the objective goal. The video was very informative.
I always get confused when talking about threats to validity! There are just so many different types; but Dr. Grande's explanation of each helped me understand it better.
This video helped me navigate causation and correlation even more precisely - recognizing the specific threats to validity will allow me to better analyze a study holistically.
We talked quite a bit about validity in statistics as well but I liked how in depth this video goes about how different things may influence the validity of research.
I did not realize there were so many threats to internal and external validity until seeing this video. I had on,y learned about two or three in undergrad and am so surprised to learn how many there actually are. It also brought to my attention that I need to be better able to differentiate between the different types.
Internal and external validity are reminding me why it is so difficult to conduct research. There are so many things to consider to ensure a research study is valid. In addition to validity, there are confounding variables and relativeness to society to consider. This makes research so intricate and thought provoking. While validity is extremely important, it is a lot to ensure is correct in a research study.
Rachel Foster Agreed that these internal and external validities are what make research so intricate and difficult. I alo find it fascinating to a certain extent. It can be a good challange brainstorming all of the different ways to prevent these things from occuring.
I had the same reaction. This video caused me to think about where the line is regarding what counts as 'valid enough' where the results from a study would be meaningful? At what point do you just toss in the towel?
This video refreshed my memory a lot in regards to internal and external validity. It is important to be mindful of this information when conducting experimental research. Thank you. - Crystal S. Jacobs
I knew that there were a lot of things that could impact a study, I always thought that there was a way to calculate the results of the study not causing as much of an issue or causing you to redo a study. This gave a lot of information about the ways to go about facing these elements, including redoing the study as an option.
As I continue my educational career, I have come to find different materials and resources helpful. I am a big fan of lists and visual aids. Therefore, the lists that begin the sections of threats to internal validity and threats to external validity extremely useful. A threat to the internal validity that I had not thought about was participant communication. Our society is one that thrives off of gossip and communication, but I thought that communication between participant's in a study would be something that could be controlled. But as I said above, we are a society that thrives off of communication therefore, there is no certainty that communication would not occur. The information in this video is extremely important and will improve my research skills.
I am new to this area of research and am surprised at the many areas that could challenge the validity of an experiment. The design of a research experiment to account for these possible validity challenges is extremely critical.
Great refresher video of terms and concepts of validity there will be much room for error so constant planning and design will be necessary to eliminate threats caused by variables
This video serves as both a good overview and refresher. Although it is a great deal of information on validity, the dissection of the two categories and the differences within each, along with the examples provided, make it easier to comprehend. There is much to consider in terms of threats to the validity of research.
This video helps me recognize the importance of understanding both internal and external threats to research validity. interestingly enough, many of the internal validity errors have been shown to have existed (not so accidentally) when many the popular psycho pharm medications were first introduced to the market. Much of that research has not been debunked but the benefits of FDA approval and widespread use continue to accrue to those companies who engaged in less than honest research and reporting.
This video was extremely informative and will be useful when conducting experimental research. It seems essential to take each of these factors into consideration when conducting and analyzing research, and also opened my awareness to the multitude of potential threats. Furthermore, it is somewhat surprising to see how many factors are capable of affecting or altering the process and outcomes within experimental research. The video did a great job in presenting important things to keep in mind!
Jacklin Skibicki I hadn't ever really considered how many things can influence a research study. LIke you said, it was somewhat surprising. I knew, of course, that a researcher had to be careful, but this video made it clear just how careful a researcher must be.
Jacklin Skibicki I concur in the realization of the various factors that could affect and threaten research. As we are learning, we don't think about how something could potentially risk the research and it could occur at any step of the process.
I agree with Ashley and Jessie. I believe the more interaction with amongst the participants and the influence of external influences such as cell phones, PC, or TV can be a threat to validity
This was an excellent video on internal and external validity. I found the list in the beginning useful to follow the remainder of the video. I had forgotten about the Hawthorne effect but this video did a great job of explaining it. I will have to be sure in research that I read and this research proposal to keep a close watch on threats to both internal and external validity.
Alaina Van Gelder I do not recall ever learning about the Hawthorne effect, so I was really happy that this video did such a great job at explaining it, as you mentioned! After watching the video, I know that I need to be extra aware and sensitive to internal and external validity and how easily it can be a factor to research studies!
This lesson effectively explains both internal and external validity threats that are important to recognize and understand. One internal validity threat that stood out to me, compensatory behavior. The example given demonstrates how the competitiveness or giving up of participates can effect the true outcome of a study.
This helped me with understanding and being aware of risk factors that play apart in research. I love the examples as that is what helps me understanding the concept.
This was video had a great and understandable layout to both the internal and external threats to experiments. I was especially drawn to the Experimenter bias threat to internal validity. It did not occur to me that if the participants found out what I was trying to do they could change their behavior. The double-blind solution to this seems like it would be pretty successful.
I definitely put the pieces together better after this video regarding internal and external validity and the dangers that can come. I also really liked the lists of the threats I never realized there were so many. All around I think this was a great video and it really helped.
Thinking of these threats to validity was something I enjoyed when I was in school because I was good at thinking of creative ways the experiment could be compromised, and ways to try to avoid them. It is astounding to think of all the different things that can affect the results and execution of an experiment, and even more astounding to think about the experiments that have already been done and the results could be compromised without the consumer even realizing. Candace made a good point below about communication. In this day and age, we are in constant communication at all hours of the day, so I wonder how an experimenter would avoid this.
That's a good point, Jessie. It's gotta be tough to keep research participants from interacting with each other and potentially skewing the results. I wonder how they would even figure that stuff out. This research study stuff is pretty iffy stuff.
Jessie Howard It is both interesting and excellent that your mind works like that, Jessie. It sounds like designing research studies would be something that you might excel at because of this personal preference. I also agree with your and Candace's point about the communication bit. It seems like everything is posted all over every social media outlet now, which would definitely make executing sound research more difficult!
Jeff Pincin I agree with both of you. It's hard to know when you are working with participants if they know each other. especially if you are seeing them separately.
Jessie Howard As the experimenter your role would be to wear many hats when trying to find possible threats to internal validity. Any time that people are involved there will always be a a risk with threats.
Jessie Howard While I was listening to this video I was thinking the same thing. When I read about a study or watch a documentary about a study, I am always trying to understand how the researcher made sure that the results were not a result of some obscure circumstance that had not been thought of.
This video was certainly helpful in gaining a much better understanding of all of the key factors that may potentially impact the research and thus impact the outcomes that were identified and / or anticipated. Even if the study is very well thought out and consideration has been given to most factors that could influence the outcome, there could still be more that we did not anticipate.
This video helped me understand the impact and risk of internal and external forces on research outcomes. It is important ot be mindful of these elements through the process.
I love learning through video! it makes everything much easier to comprehend! in this video i learned the importance of internal and external validity. internal and external validity determines the strength of a study!
Ulysa, I couldn't agree with you more! I myself learn so much faster with videos as well! It takes me forever to read concepts and explanations from the book, and it's definitely not guaranteed that I could understand. However, through live, simple, and vivid explanations and all the examples provided in the video in minutes, I find myself understand much more easily and quickly!
The video helped as an overview from research classes in undergrad many many years ago. The threat of contamination to internal validity makes sense but I didn't remember it. It would be disastrous to find that your participants have been sharing information of treatment after you have your data.
This video was good in describing the differences between internal and external validity and potential risk factors they have on the impact of your research. Even when a research design is well thought out, an issue of validity can happen at anytime.
This video was interesting and full of new information for me. I've learned about validity before, but it was a long time ago so it was a great refresher for information I already knew and also allowed me to gain more knowledge of validity. There are a lot of threats to validity and we need to be careful during research.
The video also helped me refresh my memories of certain threats to validity, such as the Hawthorne effect. I also learned plenty of valuable terms. I didn't know that there were nine subtypes of external validity.
This was an informative video. I have heard of a lot of different factors that can affect validity, Placebo Effect & Hawthorne Effect, but most were new to me. There are many different factors to consider when completing research. This video gave good examples and was easy to follow.
In all honesty, I was surprised by the length of the video when I read the title. I did not expect there to be so much to internal and external validity. However, this was a great video and I can see why it was much longer than the previous videos I watched. I know I learned most of this content in my undergraduate program but there was no way I would have remembered it all. I am actually still having trouble with understanding statistical regression. I have notes on it and have re-read it but its still not all coming together for me. What I learned that was fairly surprising to me was the ecological validity threat of "interaction of tie of measurement and treatment effect." I had not thought about a treatment taking time to be effective but it makes sense when I think about it, especially in counseling. A person can get the treatment, learn it and understand it, but not realize anything has changed for them until much later when change becomes more obvious.
Alicia Zahn I, too, have given a lot of thought about treatment needing time to take effect (therefore, the posttest not capturing the expected change because it's given too early). It seems like this could be a somewhat common occurrence which really makes it seem like such a shame to put time, effort, and resources into conducting experiments but potentially walking away without the true results.
I was surprised that i remembered most of the internal validities from undergrad classes. One internal validity aspect that I did not consider or remember was contamination. I cannot imagine how frustrating it would be to have contamination occur during an experiment. However, some of the external validities were new to me. One that fascinated me was the experimenter effect. The idea that an experimenter's charisma could alter the validity of an experiment was slightly astounding. I do recall the hawthorne effect. The novelty effect was very interesting to me and does make sense.
Susan Wilder I agree with you that contamination would be dreadful. I too, found it amazing with the experimenter effect, the charisma of one experimenter may make it hard for a different experimenter to replicate the treatment. Fascinating stuff this research!
The information in this video can be potentially important for us as we do research to keep in mind the potential threats that can change or alter our data that we gather. I always wondered about contamination, (diffusion of treatment) in regards to participants communicating with one another. You made a great point that they could communicate and discuss the treatment they are receiving, and that can change the outcome of the research, if the participants take it upon themselves to change their treatment to what another participant is receiving.
Candace Fernandez Participants communicating with one another is an major concern. If communication between participants occurs, subjects could potentially loose their neutrality. Contamination between participants could derail the entire experiment by skewing data; ultimately yielding results with very little validity.
***** I wonder if it is ethical to remove participants devices for quiet communication, like phones and computers, during the duration of an experiment. If it is a short experiment, that cold be monitored. But if it is one that repeats or they have to leave and come back, I wonder how that could be monitored. Experimenters can, of course, ask the participants to not speak to each other or people outside about the experiment, but can they ever really know for sure?
Candace Fernandez I agree. When people talk amongst themselves they tend to take on the ideals of others. There is no sure way to stop participants from talking amongst themselves, in fact it's most likely to be a natural instinct for them to want to speak of their experience with another participant who can relate. At all times we want to ensure participants are giving use their true reactions to treatment and not just hopping on the bandwagon of other participants or making other's experiences their own. Things could get skewed and participants could start to ramble or gossip. I can see how this could be a major threat to validity.
The example of adolescence was very helpful for me to understand maturation. Also the information on pretest was helpful as well just knowing that the exposure to a pretest can change the dependent variable. Solman 4 group design.
The content discussed in this video was eye opening in regards to internal and external validity. When conducting an experiment, the researcher needs to be proactive in combating validity and discerning the potential threats to the research. I was under the impression that deception during research in any form was unethical. However, by watching this video I learned that deception could be instrumental in increasing validity and decreasing participant contamination. The researcher needs to have a keen grasp on issuing deception to avoid potential harm to participants.
***** I also found the part on deception interesting and useful in increasing the validity of research and decreasing participant contamination. I also agree that issuing deception to avoid any harm to participants could be tricky and it's important for the researcher to be careful in how they present it.
As the video listed more and more threats to validity (internal or external), I could not help but think "With all of these threats, can we be sure of validity in experimental research at all??". Thankfully, some methods account for these threats by countering them. An example was a double-blind experiment to counter experimenter bias. Some of these seemed obvious to me; the placebo effect, selection, or multiple-treatment interference. Others I did not think about, such a history, pretest (or posttest) sensitization, or experimenter effect. I feel a little more intimidated of doing my own research...but that might be a good thing as I will be more conscious of these threats.
I thought that this video did a great job explaining the many threats to the validity of an experiment. I had forgotten many of them and this was a great refresher. I had also never thought of the measurement used being a threat to the validity of the experiment. However, after watching this video I can see how it would be. What your attempting to measure may only respond to a certain type of measurement. If your not using that specific measurement then you may not get accurate results.
Mandy Moore I agree! I remember learning about internal and external validity before, but it never occurred to me that there were so many different types and scenarios! The measurement being used was a great point that I had not considered. In addition, I also had not considered how the person administering the treatment could affect validity. Very interesting!
Mandy Moore Agreed! This was a great refresher and I don't know that I fully understood all of the threats, both internal and external. I will find this useful going forward.
Although there are many more threats to internal validity than there are to external validity, the significance remains the same. One threat to the validity of an experiment, internal or external, can put its findings in jeopardy and make them much less credible. Being aware of all of these threats is very important because you want to make sure that you have taken these threats into account prior to beginning research in order to obtain good data.
When doing research you have to find the right balance balance between internal and external validity or control and generalization. In the lab you can have a lot of control, but in the field you have more generalizing.
Research design is difficult in that researchers must constantly be aware of the factors that contribute to or hinder internal and external validity. Mistakes, errors, and biases can easily distort results and lead to misleading conclusions. Understanding the many threats to validity and implementing ways to avoid them are integral to becoming a good researcher and conducting beneficial research.
I really made some connections to some of the threats of internal validity such as history having an effect even so small as a weather change. Within a classroom an instructor will see examples of maturation, testing effects and instrumentation. I think that pre-testing is crucial within a study because it really gives the researcher an idea of what is already known and what pre-conceived notions there. When looking at external validity I had a question about the time piece. If a researcher runs out of time and it looks like the treatment has failed should the researcher extend the time limit or begin another study with another sampler with longer time constraints? Thanks!
Wow, there are a lot of threats to validity. Great explanations throughout, especially for the ecological external threats. I wasn't sure what that means, but the explanation was great. This will definitely be a video to re-watch several times.
Michael Smith I too thought the explanations were great! I had forgotten about many of the threats to the validity and this video did a great job of jogging my memory of them. It also exposed me to some new threats that I hadn't heard of before such as the measurement used affecting validity.
Michael Smith There are a lot of threats to validity but this video helped me distinguish the difference between them. I will also be watching this video many times!
I found it interesting that one of the threats to internal validity is selection. I agree with random assignment over the individual selecting because that person is already biased affecting the validity of the research.
As I watched this video I was pleased that I had remembered most of these terms with internal and external validity. It seems that there are many more threats to internal validity than external validity. It also seems that the threats to internal validity are more complicated while the threats to external validity are a bit more straight forward. One of the threats to internal validity that I had not considered was Selection. I had not been aware that there are research studies that allow participants to pick their own group for the study. To me it seems odd that a researcher would design a study this way because of the implications to the validity to begin with. I did not really understand fully the concept of Statistical Regression. I understand the basic premise but what I am struggling with is why it occurs to begin with.
There are many threats to consider that can affect the validity of the study. I think that one most familiar to me is the placebo affect and the hawthorn affect. I work with young children who have behavior problems and for the first session we observe the interaction between the parent and the child through a one way mirror. Because the children we observe are so young, they may not realize that we are observing them, but I wonder if the parent's behavior changes since they are aware they are being observed. Haven't thought of that until now.
Great video, Dr. Grande. I wonder how much the novelty effect has impacted some of the standardized psychological testing for executive function, since a lot of the puzzle games, card-sorting tasks, recall lists, and stop cue routines are not really tasks for which clients (especially adult clients) have strong contextual reference. And, for that matter, the context issues may be large for children as well, since these sorts of tests usually implement rules unlike those in tasks at school. I suppose with replication it becomes less of a concern, but I do wonder how much the novelty angle impacts the scales.
All of these threats are a possibility. I like the idea of employing deception during demand characteristics as long as they are debriefed at the end of the experiment. I can see where individuals would want the person conducting the experiment to succeed and want to "help" with the results.
I was surprised that I had forgot some of the threats, such as confounding variables and history, that can compromise the internal and external validity of research and was reminded how important it is to be aware of these threats.
Kimberly Dixon I wasn't aware of (or didn't remember) each of the potential threats as well! This video definitely showed the importance of awareness and consideration surrounding both internal and external threats to validity within experimental research!
Aside from the concerns about internal validity with experimental methods, It is interesting that psychology still tends to favor experiments, which seem to me to have bigger problems with external validity and generalizability than anything else. There are so many experiments with undergraduate students, for instance, whose results are really debatably generalizable to any general population. And it is so difficult to simulate the outside world on any kind of realistic level in the laboratory.
Katie, I completely agree with you. I remember doing two experiments as a Psych major and feeling limited in terms of my sample. I also think you made valid points in terms of validity with these undergraduate experiments, as we learned from the video.
Internal and external validity can have certain variables that may affect the outcome of a study. The one that stood out for me was that of Demand Characteristics. One can never assume that their participants are not going to look for cues to the outcome of a hypothesis. The researcher has to almost use deception in order for the participant to continue without being bias toward the study. A debriefing is nessecary to avoid any harm.
Toniette Morda Demand characteristics are interesting and it makes sense that people will be naturally curious about what they are part of. The trouble is that curiosity can be harmful, even when it might seem like it is not to participants. Deception is an option which is a bit tricky and has to be done with caution, even with debriefing.
It's good that they're able to put names to these things. That must be helpful in describing what happens. I would like to see how these researchers find out if/when this stuff happens. I'm having a bit of trouble understanding the difference between internal and external validity. I guess it's pretty self-explanatory. Internal issues with validity are things within the study, but external are outside factors. Is there more to it though? Maybe it would help to see examples of these.
Wow, there are a lot of threats to internal and external validity! It makes me wonder if there are ever truly sound experiments that manage to go unscathed by these threats. It seems nearly impossible for an experimenter to ever know for sure, especially since there is a high number of threats that could easily fly under the radar (like the Hawthorne effect).
I guess documentation is very important while conducting a research and each threat may not apply to every study. Not all studies will require observing a person perhaps.
Prior to watching the video, I thought that internal validity was the most important and external validity was not as important. Although internal validity is necessary in order to ensure accuracy of outcome within your own experiment, external validity is extremely important as well. Without external validity, your results will not be applicable to the general population and therefore, not really beneficial.
This video was a refresher for me. I surprised myself at how much I remembered threats to external and internal validity from undergrad. I liked how Dr. Grande did not just list what was a threat to each, but broke down each threat so that it was viewer friendly. Definitely helpful!
Danielle Maldonado I also liked how Dr. Grande broke down and explained each threat for internal; and external validity. It helped me understand what to be on the look out for when I check the validity of a study. However, this was not a refresher video for me, but rather an entire new look on validity. I do not remember going over the threats in undergrad, but I have a greater understanding due to this video.
This video had so much information packed into it about the threats to validity in research. There are so many different things that can affect the validity, then to add on participants interacting together, it's a lot to keep in mind. The explanation of the ecological threats was very helpful.
Dr. Grande- This information proven to give me understanding internal and external validity. This information allowed me to think back to my course in undergrad which allowed me to process the differences. It is important to keep in mind, that we must keep the experimental groups separate or the scores would not be accurate. Thank you!
I have an exam in research methods in the morning and I’m so glad I found this! Yes! Thank you Dr. Grande 🙌
There are so many things that can threaten the validity of your research. I'm glad that he talked about them in detail to help avoid error and so that we would know if we are using the process when analyzing the research.
Thank you for the comprehensive treatment of this subject. The list of possible ways for an experiment to lose validity surprised me, especially the list of threats to external validity. I expected the generalization problem, but many of the other issues, such as the novelty effect, were new to me.
Dr. Grande,
This video has some great examples of the different types of internal and external threats. Your examples really helped me understand some of the harder to understand types. This video showed me how difficult it is to keep your research valid, especially with school age children due to their maturation.
This video is extremely helpful to me, as after reviewing all the threats to external and internal validity of an experimental research, I realized how careful and cautious researchers have to be to make sure of validity of a study. I like that you also provided ways to prevent or improve the threats to validity. However, I need to review this very often in order to apply these concepts and cautions into practice.
I learned so much about the types of threats to internal and external validity. I would always be confused when reading research articles because I did not understand the correct definitions of mortality or deception in a study. I now understand that mortality refers to participants dropping out of a study, and deception can be used to avoid demand characteristics. This video will help me when reading future articles and in designing my own research experiment.
It is very important to know how to recognize the validity of data found during the design portion of your research. Knowing and understanding internal and external validity will prevent making mistakes early on in the research process. Providing examples in laymen's terms was very helpful as well.
The video helped me to understand how important it is to be aware of all of the possible threats to both internal and external validity when conducting research experiments.
Thank you for this refresher on validity, there are many factors to consider when conducting research in a manner that protects validity. It seems that many of these would be accidental or easy to overlook. A good reminder in this video is the value of a double-blind experiment to remove inadvertent biases by the experimenters.
This video helped me realize how detailed an experiment can be with all of the threats to internal and external validity. Just one threat can change the outcome of an experiment. It seems as if there is just as much attention to the preparation of a research as the conducting of a research. Once again, the examples help paint a pretty vivid "big picture" for me.
Thank you for sharing this video Dr. Grande. There are many factors that can manipulate the study, but the two that caught my attention was the contamination and compensatory behaviors factors. It's eye-opening to hear the participants can manipulate the results by knowing what the other groups are being tested for.
This video made me realize how important it is to be aware and be mindful to potential risk factors that could jeopardize your research. It could happen at any step of the process, not just during analyzing data step.
Jasmine Aviles
yes i agree. doing research has so many levels to it. It can be very difficult to control everything
Dr. Grande, I did not realize the pretest contributes to a change in the DV, threatening the interval validity. Thanks.
This was a nice refresher course for me in internal and external validity. Unlike some of the other topics that are covered in Dr. Grande's videos I (surprisingly) have heard of internal and external validity from past research classes. However, these classes happened long ago and I have since forgotten quite a bit about them. What I found most interesting about this video was the population validity threat to external validity. This reminded me of a quote about going to the ocean, taking a cup of water, seeing that there is no fish in the cup, and therefore deducing that there are no fish in the ocean. While this is an extreme example I believe that that same thought process can sometimes happen in studies.
I appreciated the second scenario for statistical regression. Dr. Grande provided an example of the possibility of scores moving towards the mean when they are measured multiple times. At first this did not make sense to me, but as he further explained how the changes in scores could be perceived as benefits from the treatment, I was able to better understand this concept. Thank you!
This material is slowly, but surely starting to come back to me. I have heard about several of the threats to internal validity (e.g., experimenter bias, confounding variables). However, I will say that I don't recall learning about ecological validity or population validity. I suppose that we all learn something new every day! While some of the threats to internal/external validity probably can't be avoided completely, it's important that researchers stay aware of these threats so that they can reduce them as much as possible.
I found this video very clarifying in order not to make mistakes that may end up compromising the validity of a research. Being careful at the time of the design of a research not only would save a lot of time but also would assure us an accurate result
Roberto, I agree with you. This video helped a lot with the clarification of validity, both internal and external to avoid making mistakes.
It was definitely great to be reminded of all of the threats to internal validity; I had forgotten about all of them! Contamination was one threat to internal validity that I had not thought about that would have a major impact on differences between various treatment groups. For amateur researchers, they may not be as strict about keeping their participants separate when waiting to participate in their study, or when they are leaving, which could adversely effect any post-participation results. I also had not thought about just how important it is to be wary of having experimenter bias. Since we may have an obvious vested in our research, it is advantageous to have a double-blind experiment so that we are not tempted to report only what we want to report or neglect to see important indicators that may pop up that experimenter bias may make convoluted.
This video did a great job explaining the importance of internal and external validity. Something as simple as selecting a sample that is not truly random can throw off results. Confounding variables were always a mystery to me in undergrad.
The pretest and posttest concept was new to me, even after having done research, both clinical and experimental, in undergrad. The safer the hypothesis' route of testing, the better--and more efficient for the PI and RAs!
The specific and realistic examples are very helpful in understanding the different concepts associated with internal and external validity, especially as there are so many things that could affect a study's validity. I also found it helpful that common threats to internal validity were pointed out. I found it useful that tips were given such as it being better to select instrumentation measures before the experiment and continue to use the same ones to preserve the internal validity of the study. As before, pointing out similar or interchangeable concepts such as attrition and mortality eases confusion. I would be interested to learn about the best ways to account for the most common threats to internal and external validity.
Very good overview of internal and external validity, and the discussed examples really help make it more clear.
By watching this video, I was reminded how many different threats to internal and external validity there is. When the video talked about population validity, it got me thinking about how much a person really does have to consider when they do a research study. By considering the population sample, if one thing is wrong with it, it could throw your whole study off, which is something that needs to be fully considered and remembered when conducting a study. Also, when mentioned how sensitive results can be and how time can be a factor, I realized that validity is important in studies especially with things such as technology, because it is always changing, so the results may not always be valid for that time period, or even applicable.
This overview brought back memories of my Experimental Psychology classes in undergrad. I really appreciated the real life examples provided which made it much more memorable.
It was interesting too see all of the internal and external influences to validity. It really got me to thinking about all of the threats to validity that are possibilities during an experiment. There is no fire proof way to ensure an experiment will not be compromised but this video shared a nice list of threats (internal and external) to look out for. I really enjoyed this video.
This was an informational video which makes me aware of the need for understanding validity and flaws in validity whether translating psychology or in creating new studies for future development. I know this has been touched on in other classes, but this really gives me what I feel is a well rounded view of potential issues which may give studies false results (in both positive and negative ways). I am looking forward to trying to be more cognizant of potential risk factors which are posed as I read future studies and deal with the author's/authors' conclusion(s).
There are some many different ways that a study can be influenced. It is completely important to keep awareness to all the risk factors that can influence a study in order for the validity to be as close to the objective goal. The video was very informative.
I always get confused when talking about threats to validity! There are just so many different types; but Dr. Grande's explanation of each helped me understand it better.
This video helped me navigate causation and correlation even more precisely - recognizing the specific threats to validity will allow me to better analyze a study holistically.
+Tracy Marshall-Johnson Ashamed to admit that I never understood what a double-blind experiment was.
We talked quite a bit about validity in statistics as well but I liked how in depth this video goes about how different things may influence the validity of research.
I did not realize there were so many threats to internal and external validity until seeing this video. I had on,y learned about two or three in undergrad and am so surprised to learn how many there actually are. It also brought to my attention that I need to be better able to differentiate between the different types.
Internal and external validity are reminding me why it is so difficult to conduct research. There are so many things to consider to ensure a research study is valid. In addition to validity, there are confounding variables and relativeness to society to consider. This makes research so intricate and thought provoking. While validity is extremely important, it is a lot to ensure is correct in a research study.
Rachel Foster Agreed that these internal and external validities are what make research so intricate and difficult. I alo find it fascinating to a certain extent. It can be a good challange brainstorming all of the different ways to prevent these things from occuring.
I had the same reaction. This video caused me to think about where the line is regarding what counts as 'valid enough' where the results from a study would be meaningful? At what point do you just toss in the towel?
This video refreshed my memory a lot in regards to internal and external validity. It is important to be mindful of this information when conducting experimental research. Thank you. - Crystal S. Jacobs
I knew that there were a lot of things that could impact a study, I always thought that there was a way to calculate the results of the study not causing as much of an issue or causing you to redo a study. This gave a lot of information about the ways to go about facing these elements, including redoing the study as an option.
As I continue my educational career, I have come to find different materials and resources helpful. I am a big fan of lists and visual aids. Therefore, the lists that begin the sections of threats to internal validity and threats to external validity extremely useful. A threat to the internal validity that I had not thought about was participant communication. Our society is one that thrives off of gossip and communication, but I thought that communication between participant's in a study would be something that could be controlled. But as I said above, we are a society that thrives off of communication therefore, there is no certainty that communication would not occur. The information in this video is extremely important and will improve my research skills.
I am new to this area of research and am surprised at the many areas that could challenge the validity of an experiment. The design of a research experiment to account for these possible validity challenges is extremely critical.
Great refresher video of terms and concepts of validity there will be much room for error so constant planning and design will be necessary to eliminate threats caused by variables
This video serves as both a good overview and refresher. Although it is a great deal of information on validity, the dissection of the two categories and the differences within each, along with the examples provided, make it easier to comprehend. There is much to consider in terms of threats to the validity of research.
This video helps me recognize the importance of understanding both internal and external threats to research validity. interestingly enough, many of the internal validity errors have been shown to have existed (not so accidentally) when many the popular psycho pharm medications were first introduced to the market. Much of that research has not been debunked but the benefits of FDA approval and widespread use continue to accrue to those companies who engaged in less than honest research and reporting.
This video was extremely informative and will be useful when conducting experimental research. It seems essential to take each of these factors into consideration when conducting and analyzing research, and also opened my awareness to the multitude of potential threats. Furthermore, it is somewhat surprising to see how many factors are capable of affecting or altering the process and outcomes within experimental research. The video did a great job in presenting important things to keep in mind!
Jacklin Skibicki I hadn't ever really considered how many things can influence a research study. LIke you said, it was somewhat surprising. I knew, of course, that a researcher had to be careful, but this video made it clear just how careful a researcher must be.
Jacklin Skibicki I concur in the realization of the various factors that could affect and threaten research. As we are learning, we don't think about how something could potentially risk the research and it could occur at any step of the process.
I agree with Ashley and Jessie. I believe the more interaction with amongst the participants and the influence of external influences such as cell phones, PC, or TV can be a threat to validity
This was an excellent video on internal and external validity. I found the list in the beginning useful to follow the remainder of the video. I had forgotten about the Hawthorne effect but this video did a great job of explaining it. I will have to be sure in research that I read and this research proposal to keep a close watch on threats to both internal and external validity.
Alaina Van Gelder I do not recall ever learning about the Hawthorne effect, so I was really happy that this video did such a great job at explaining it, as you mentioned! After watching the video, I know that I need to be extra aware and sensitive to internal and external validity and how easily it can be a factor to research studies!
This lesson effectively explains both internal and external validity threats that are important to recognize and understand. One internal validity threat that stood out to me, compensatory behavior. The example given demonstrates how the competitiveness or giving up of participates can effect the true outcome of a study.
This helped me with understanding and being aware of risk factors that play apart in research. I love the examples as that is what helps me understanding the concept.
This was video had a great and understandable layout to both the
internal and external threats to experiments. I was especially drawn to
the Experimenter bias threat to internal validity. It did not occur to
me that if the participants found out what I was trying to do they
could change their behavior. The double-blind solution to this seems
like it would be pretty successful.
I definitely put the pieces together better after this video regarding internal and external validity and the dangers that can come. I also really liked the lists of the threats I never realized there were so many. All around I think this was a great video and it really helped.
Thinking of these threats to validity was something I enjoyed when I was in school because I was good at thinking of creative ways the experiment could be compromised, and ways to try to avoid them. It is astounding to think of all the different things that can affect the results and execution of an experiment, and even more astounding to think about the experiments that have already been done and the results could be compromised without the consumer even realizing. Candace made a good point below about communication. In this day and age, we are in constant communication at all hours of the day, so I wonder how an experimenter would avoid this.
That's a good point, Jessie. It's gotta be tough to keep research participants from interacting with each other and potentially skewing the results. I wonder how they would even figure that stuff out. This research study stuff is pretty iffy stuff.
Jessie Howard It is both interesting and excellent that your mind works like that, Jessie. It sounds like designing research studies would be something that you might excel at because of this personal preference. I also agree with your and Candace's point about the communication bit. It seems like everything is posted all over every social media outlet now, which would definitely make executing sound research more difficult!
Jeff Pincin I agree with both of you. It's hard to know when you are working with participants if they know each other. especially if you are seeing them separately.
Jessie Howard As the experimenter your role would be to wear many hats when trying to find possible threats to internal validity. Any time that people are involved there will always be a a risk with threats.
Jessie Howard While I was listening to this video I was thinking the same thing. When I read about a study or watch a documentary about a study, I am always trying to understand how the researcher made sure that the results were not a result of some obscure circumstance that had not been thought of.
This video was certainly helpful in gaining a much better understanding of all of the key factors that may potentially impact the research and thus impact the outcomes that were identified and / or anticipated. Even if the study is very well thought out and consideration has been given to most factors that could influence the outcome, there could still be more that we did not anticipate.
This video helped me understand the impact and risk of internal and external forces on research outcomes. It is important ot be mindful of these elements through the process.
I love learning through video! it makes everything much easier to comprehend! in this video i learned the importance of internal and external validity. internal and external validity determines the strength of a study!
Ulysa, I couldn't agree with you more! I myself learn so much faster with videos as well! It takes me forever to read concepts and explanations from the book, and it's definitely not guaranteed that I could understand. However, through live, simple, and vivid explanations and all the examples provided in the video in minutes, I find myself understand much more easily and quickly!
This video reminds me the importance of having external validity in order to link the results of a study to the general population.
The video helped as an overview from research classes in undergrad many many years ago. The threat of contamination to internal validity makes sense but I didn't remember it. It would be disastrous to find that your participants have been sharing information of treatment after you have your data.
This video was good in describing the differences between internal and external validity and potential risk factors they have on the impact of your research. Even when a research design is well thought out, an issue of validity can happen at anytime.
This video was interesting and full of new information for me. I've learned about validity before, but it was a long time ago so it was a great refresher for information I already knew and also allowed me to gain more knowledge of validity. There are a lot of threats to validity and we need to be careful during research.
The video also helped me refresh my memories of certain threats to validity, such as the Hawthorne effect. I also learned plenty of valuable terms. I didn't know that there were nine subtypes of external validity.
This was an informative video. I have heard of a lot of different factors that can affect validity, Placebo Effect & Hawthorne Effect, but most were new to me. There are many different factors to consider when completing research. This video gave good examples and was easy to follow.
I remember studying these topics when I was getting my B.A. in Psychology! It was nice to refresh this information.
In all honesty, I was surprised by the length of the video when I read the title. I did not expect there to be so much to internal and external validity. However, this was a great video and I can see why it was much longer than the previous videos I watched. I know I learned most of this content in my undergraduate program but there was no way I would have remembered it all. I am actually still having trouble with understanding statistical regression. I have notes on it and have re-read it but its still not all coming together for me. What I learned that was fairly surprising to me was the ecological validity threat of "interaction of tie of measurement and treatment effect." I had not thought about a treatment taking time to be effective but it makes sense when I think about it, especially in counseling. A person can get the treatment, learn it and understand it, but not realize anything has changed for them until much later when change becomes more obvious.
Alicia Zahn I, too, have given a lot of thought about treatment needing time to take effect (therefore, the posttest not capturing the expected change because it's given too early). It seems like this could be a somewhat common occurrence which really makes it seem like such a shame to put time, effort, and resources into conducting experiments but potentially walking away without the true results.
I was surprised that i remembered most of the internal validities from undergrad classes. One internal validity aspect that I did not consider or remember was contamination. I cannot imagine how frustrating it would be to have contamination occur during an experiment.
However, some of the external validities were new to me. One that fascinated me was the experimenter effect. The idea that an experimenter's charisma could alter the validity of an experiment was slightly astounding. I do recall the hawthorne effect. The novelty effect was very interesting to me and does make sense.
Susan Wilder I agree with you that contamination would be dreadful. I too, found it amazing with the experimenter effect, the charisma of one experimenter may make it hard for a different experimenter to replicate the treatment. Fascinating stuff this research!
The information in this video can be potentially important for us as we do research to keep in mind the potential threats that can change or alter our data that we gather. I always wondered about contamination, (diffusion of treatment) in regards to participants communicating with one another. You made a great point that they could communicate and discuss the treatment they are receiving, and that can change the outcome of the research, if the participants take it upon themselves to change their treatment to what another participant is receiving.
Candace Fernandez Participants communicating with one another is an major concern. If communication between participants occurs, subjects could potentially loose their neutrality. Contamination between participants could derail the entire experiment by skewing data; ultimately yielding results with very little validity.
***** I wonder if it is ethical to remove participants devices for quiet communication, like phones and computers, during the duration of an experiment. If it is a short experiment, that cold be monitored. But if it is one that repeats or they have to leave and come back, I wonder how that could be monitored. Experimenters can, of course, ask the participants to not speak to each other or people outside about the experiment, but can they ever really know for sure?
Candace Fernandez I agree. When people talk amongst themselves they tend to take on the ideals of others. There is no sure way to stop participants from talking amongst themselves, in fact it's most likely to be a natural instinct for them to want to speak of their experience with another participant who can relate. At all times we want to ensure participants are giving use their true reactions to treatment and not just hopping on the bandwagon of other participants or making other's experiences their own. Things could get skewed and participants could start to ramble or gossip. I can see how this could be a major threat to validity.
The example of adolescence was very helpful for me to understand maturation. Also the information on pretest was helpful as well just knowing that the exposure to a pretest can change the dependent variable. Solman 4 group design.
The content discussed in this video was eye opening in regards to internal and external validity. When conducting an experiment, the researcher needs to be proactive in combating validity and discerning the potential threats to the research. I was under the impression that deception during research in any form was unethical. However, by watching this video I learned that deception could be instrumental in increasing validity and decreasing participant contamination. The researcher needs to have a keen grasp on issuing deception to avoid potential harm to participants.
***** I also found the part on deception interesting and useful in increasing the validity of research and decreasing participant contamination. I also agree that issuing deception to avoid any harm to participants could be tricky and it's important for the researcher to be careful in how they present it.
As the video listed more and more threats to validity (internal or external), I could not help but think "With all of these threats, can we be sure of validity in experimental research at all??". Thankfully, some methods account for these threats by countering them. An example was a double-blind experiment to counter experimenter bias. Some of these seemed obvious to me; the placebo effect, selection, or multiple-treatment interference. Others I did not think about, such a history, pretest (or posttest) sensitization, or experimenter effect. I feel a little more intimidated of doing my own research...but that might be a good thing as I will be more conscious of these threats.
I thought that this video did a great job explaining the many threats to the validity of an experiment. I had forgotten many of them and this was a great refresher. I had also never thought of the measurement used being a threat to the validity of the experiment. However, after watching this video I can see how it would be. What your attempting to measure may only respond to a certain type of measurement. If your not using that specific measurement then you may not get accurate results.
Mandy Moore I agree! I remember learning about internal and external validity before, but it never occurred to me that there were so many different types and scenarios! The measurement being used was a great point that I had not considered. In addition, I also had not considered how the person administering the treatment could affect validity. Very interesting!
Mandy Moore Agreed! This was a great refresher and I don't know that I fully understood all of the threats, both internal and external. I will find this useful going forward.
Although there are many more threats to internal validity than there are to external validity, the significance remains the same. One threat to the validity of an experiment, internal or external, can put its findings in jeopardy and make them much less credible. Being aware of all of these threats is very important because you want to make sure that you have taken these threats into account prior to beginning research in order to obtain good data.
When doing research you have to find the right balance balance between internal and external validity or control and generalization. In the lab you can have a lot of control, but in the field you have more generalizing.
Research design is difficult in that researchers must constantly be aware of the factors that contribute to or hinder internal and external validity. Mistakes, errors, and biases can easily distort results and lead to misleading conclusions. Understanding the many threats to validity and implementing ways to avoid them are integral to becoming a good researcher and conducting beneficial research.
I really made some connections to some of the threats of internal validity such as history having an effect even so small as a weather change. Within a classroom an instructor will see examples of maturation, testing effects and instrumentation. I think that pre-testing is crucial within a study because it really gives the researcher an idea of what is already known and what pre-conceived notions there. When looking at external validity I had a question about the time piece. If a researcher runs out of time and it looks like the treatment has failed should the researcher extend the time limit or begin another study with another sampler with longer time constraints? Thanks!
Wow, there are a lot of threats to validity. Great explanations throughout, especially for the ecological external threats. I wasn't sure what that means, but the explanation was great. This will definitely be a video to re-watch several times.
Michael Smith I too thought the explanations were great! I had forgotten about many of the threats to the validity and this video did a great job of jogging my memory of them. It also exposed me to some new threats that I hadn't heard of before such as the measurement used affecting validity.
Michael Smith There are a lot of threats to validity but this video helped me distinguish the difference between them. I will also be watching this video many times!
The video, as much as it is informative, it serves as caution to be aware of the dangers and risks involved in internal and external validity.
I found it interesting that one of the threats to internal validity is selection. I agree with random assignment over the individual selecting because that person is already biased affecting the validity of the research.
John, I also find it interesting. I like how some of the ways to overcome threats to validity were discussed.
Yes this video did a great job in describing variables other than the IV and DV
As I watched this video I was pleased that I had remembered most of these terms with internal and external validity. It seems that there are many more threats to internal validity than external validity. It also seems that the threats to internal validity are more complicated while the threats to external validity are a bit more straight forward. One of the threats to internal validity that I had not considered was Selection. I had not been aware that there are research studies that allow participants to pick their own group for the study. To me it seems odd that a researcher would design a study this way because of the implications to the validity to begin with. I did not really understand fully the concept of Statistical Regression. I understand the basic premise but what I am struggling with is why it occurs to begin with.
There are many threats to consider that can affect the validity of the study. I think that one most familiar to me is the placebo affect and the hawthorn affect. I work with young children who have behavior problems and for the first session we observe the interaction between the parent and the child through a one way mirror. Because the children we observe are so young, they may not realize that we are observing them, but I wonder if the parent's behavior changes since they are aware they are being observed. Haven't thought of that until now.
Great video, Dr. Grande. I wonder how much the novelty effect has impacted some of the standardized psychological testing for executive function, since a lot of the puzzle games, card-sorting tasks, recall lists, and stop cue routines are not really tasks for which clients (especially adult clients) have strong contextual reference. And, for that matter, the context issues may be large for children as well, since these sorts of tests usually implement rules unlike those in tasks at school. I suppose with replication it becomes less of a concern, but I do wonder how much the novelty angle impacts the scales.
All of these threats are a possibility. I like the idea of employing deception during demand characteristics as long as they are debriefed at the end of the experiment. I can see where individuals would want the person conducting the experiment to succeed and want to "help" with the results.
I was surprised that I had forgot some of the threats, such as confounding variables and history, that can compromise the internal and external validity of research and was reminded how important it is to be aware of these threats.
Kimberly Dixon I wasn't aware of (or didn't remember) each of the potential threats as well! This video definitely showed the importance of awareness and consideration surrounding both internal and external threats to validity within experimental research!
Aside from the concerns about internal validity with experimental methods, It is interesting that psychology still tends to favor experiments, which seem to me to have bigger problems with external validity and generalizability than anything else. There are so many experiments with undergraduate students, for instance, whose results are really debatably generalizable to any general population. And it is so difficult to simulate the outside world on any kind of realistic level in the laboratory.
Katie, I completely agree with you. I remember doing two experiments as a Psych major and feeling limited in terms of my sample. I also think you made valid points in terms of validity with these undergraduate experiments, as we learned from the video.
Internal and external validity can have certain variables that may affect the outcome of a study. The one that stood out for me was that of Demand Characteristics. One can never assume that their participants are not going to look for cues to the outcome of a hypothesis. The researcher has to almost use deception in order for the participant to continue without being bias toward the study. A debriefing is nessecary to avoid any harm.
Toniette Morda Demand characteristics are interesting and it makes sense that people will be naturally curious about what they are part of. The trouble is that curiosity can be harmful, even when it might seem like it is not to participants. Deception is an option which is a bit tricky and has to be done with caution, even with debriefing.
Thank you!
Clear and thorough!!
It's good that they're able to put names to these things. That must be helpful in describing what happens. I would like to see how these researchers find out if/when this stuff happens. I'm having a bit of trouble understanding the difference between internal and external validity. I guess it's pretty self-explanatory. Internal issues with validity are things within the study, but external are outside factors. Is there more to it though? Maybe it would help to see examples of these.
Very informative
Wow, there are a lot of threats to internal and external validity! It makes me wonder if there are ever truly sound experiments that manage to go unscathed by these threats. It seems nearly impossible for an experimenter to ever know for sure, especially since there is a high number of threats that could easily fly under the radar (like the Hawthorne effect).
I agree with you that it might be difficult to consider ever threat.
I guess documentation is very important while conducting a research and each threat may not apply to every study. Not all studies will require observing a person perhaps.
Prior to watching the video, I thought that internal validity was the most important and external validity was not as important. Although internal validity is necessary in order to ensure accuracy of outcome within your own experiment, external validity is extremely important as well. Without external validity, your results will not be applicable to the general population and therefore, not really beneficial.
great list of threats.