Mediation with Bootstrapping

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  • Опубліковано 3 гру 2024

КОМЕНТАРІ • 66

  • @JoceOnFire
    @JoceOnFire  11 років тому +3

    Hi Emma,
    You are very welcome. I am delighted to hear that I was able to help someone else out there. It motivates me to post more videos like these.
    Cheers!

  • @riadvm
    @riadvm 10 років тому

    Thank you so much for this video! You covered every parts that someone who is looking for this video for sure has to know and do.

  • @emmah6216
    @emmah6216 11 років тому +1

    Hi Jocelyn, thank you for making my life so much easier :) Been trying to get my head around this all day. I'm so happy there are people like you making these awesome videos!
    Em xx

  • @aquablueemerald
    @aquablueemerald 9 років тому

    Hey Jocelyn... i would to thank you so much for this very informative video... you literally saved my life.... i was so confused about performing mediation analysis for my research... may god bless you with all good things in your life.... can't thank you enough..... lots of love from Malaysia~

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Thank you for your question Emma! If the A and B paths are significant, but the indirect effect is not, it is possible that you lack statistical power to detect the effect. If possible, try to increase the sample size. My guess is that your confidence interval is very close to being significant. Have you tried running the analysis again using 5000 samples? There are some small variations among bootstraps and that might help you get the confidence interval that you need.

  • @swsiew
    @swsiew 11 років тому

    Hi Jocelyn,
    Thank you for the wonderful explanation and video clip. It's very information and well organized.

  • @JoceOnFire
    @JoceOnFire  11 років тому

    HI!
    Thank you for asking this important question. There are many ways of getting standardized betas. You could (1) run Multiple Regression Analyses for every path or (2) standardize your variables before running the analysis. The latter solution will provide you with standardized coefficients, however the bootstrap confidence interval would not be those of the standardized effects. Remember also that standardized effects of dichotomous predictors do not yield very substantive interpretation.

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Hi there!
    Thank you for your comment. Traditionally, Baron and Kenny (1986) made the argument that the C-path is necessary to test mediation. However, in a more recent paper (see Kenny, Kashy, Bolger, 1998), Kenny suggested that the C-path was no longer necessary in order to test for mediation. The latter argument has caught on and it is not uncommon that researchers test the ab path even if the c-path is not significant. After all, mediation is primarily about the ab path, not the c-path.

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Hi Hazman,
    Thank you for your question! I am much surprised by Preacher's comment. I am pretty sure he meant the C-path was optional (i.e., only the ab path is mandatory). I personally cannot conceive how mediation is possible without the a-path. At least something needs to be significant! ;)

  • @inexpensivetrick
    @inexpensivetrick 9 років тому

    The video was unbelievably helpful. I might actually finish my research by the deadline. Thank you!!!!!!!

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Hi Justin,
    Bootstrapping can be used if you are comparing groups, no problem!

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Hi Ye,
    including control variables is very simple. In the INDIRECT SPSS window, insert your control variables (e.g., demographics) in the Covariate(s) box. Et voilà!

  • @bjorngoossens9108
    @bjorngoossens9108 9 років тому

    Great video! Especially the tips about how to describe it in a thesis were very nice!

  • @mercutiosullivan
    @mercutiosullivan 11 років тому

    Hi Jocelyn! Very nice video...clear and useful, thanks a lot!

  • @lethecat
    @lethecat 10 років тому

    Thank you so much for this informative, considerable demonstration.

  • @icetyrael1
    @icetyrael1 11 років тому

    What an awesome video. Thanks a lot! This thorough explanation is helping me a lot for my thesis and made me understand the entire process way faster.
    I have a model
    IV: network configurations
    DV: performance
    M: entrepreneurial orientation
    the IV was originally built up from two constructs, namely network size and network diversity
    network size makes for a great mediation model
    network diversity certainly not
    should I do both, explain the issue, then drop diversity and just use only size?

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Hi!
    The idea is that if the Confidence Interval includes 0 then the indirect effect is not significant. This is the case with your CI. A simple trick: If the confidence interval includes two different signs + and -, then it is not significant. If the CI has two similar signs e.g., - and -, or + and +, then the indirect effect is significant. Hope that helps!

  • @abdurahmanaliye2616
    @abdurahmanaliye2616 10 років тому

    thanks again Jocelyn. i am using Smart PLS.

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Hi Emma
    It is possible that 80 cases is too little. Although I have seen significant indirect effect with fewer cases. It all boils down to the notion of effect size. I would recommend increasing the sample size if the effect your examining is low in magnitude. Good luck!

  • @amalaokpalanze9772
    @amalaokpalanze9772 10 років тому +4

    hi Jocelyn thank you for this video. please i have a question. how can i conduct mediation when i have 2 independent variables, 1 dependent variable and 1 mediator variable?

  • @KamalAsasi
    @KamalAsasi 10 років тому

    Thank you dear Jocelyn for this productive and informative lecture, I wish you all the best. Keep the good work up :)

  • @Hazmanshah1
    @Hazmanshah1 11 років тому

    Hi Jocelyn, I find the video a good addition to my materials for my students. I have one question though. Recently, hayes mentioned in his workshop on mediation that significance of the a path is not necessary to determine mediation. Like to hear your comments on this. My opinion is that if the requirement of a significance a path is not required, then the mediation could just be viewed as another independent variable.

  • @emmah6216
    @emmah6216 11 років тому

    Hey Jocelyn, thank you so much for the reply! I wanted to see whether there were indirect effects separately for males and females so split the sample, and then there was only 80 cases for males- perhaps that's too small a sample? This was with 5000 bootstrap re-samples too. CI was -.07 - .56 so I don't know what's going on...
    Can't wait for the regression ;-)
    Thanks again,
    Em x

  • @yeliu4092
    @yeliu4092 11 років тому

    Hi Jocelyn, your show is very helpful to my research, many thanks!!!
    However, How to add in some control variables in the mediation effects, such as demographics?

  • @petra_b709
    @petra_b709 11 років тому

    Thanks! You're video is very instructive.

  • @65sm
    @65sm 11 років тому

    Thank you very much for an excellent & well explained tutorial!
    May I ask a question regarding reporting confidence intervals please?
    I have been given a handout with mediation analysis assumption checking & bootstrapping, but at BOTH 95% & 99% CI to do an APA write-up on. I cannot work out which CI I should report. Looking at the indirect effect of x on y, both the LLCI & ULCI for 95% & 99% are negative values (so don't include zero). The sample size is 120. Any advice please? Thanks

  • @emmah6216
    @emmah6216 11 років тому

    I'd love you to post more videos like these, on hierarchical regression please XD
    Could I be cheeky and ask a question? I've just conducted the analysis in the vid, and the a and b paths are significant, but 0 is included in the confidence intervals. So I was wondering how you would report this? Do you say that the mediation model is non-significant, even though the a and b paths are significant?
    Would really appreciate any help :)
    Thanks,
    Em x

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Hi!
    I've never tried with Smart PLS. However, if it is an issue, you can perform bootstrapping using the free SPSS trial version.

  • @Migsterxoxo
    @Migsterxoxo 11 років тому +1

    Very nice tutorial Jocelyn, thanks for posting this.
    In the path modelling, issues mostly lie in interpreting the results (as usual). For example, how would you interpret this outcome: A-path significant, B-path non-significant, C-path (total effect) significant, and C1-path (direct effect of IV on DV), non significant?

    • @JoceOnFire
      @JoceOnFire  10 років тому

      In that case you would simply say that the A and C paths are significant, but not the b-path, which suggests that the proposed mediator is not the mechanism at play.

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Hi! I'm glad you found the video helpful. Could you please send me one of the paper you are referring to? I'd be happy to take a look at it to help you out.

  • @nonstopexpo
    @nonstopexpo 11 років тому

    Thanks Jocelyn, was a great help ! The only problem I have is that the coefficients differ with the coefficients that I get when I do a regression analysis on the individual paths. Do you have any idea how that's possible? Regards Omar

  • @Austin_IK
    @Austin_IK 11 років тому

    Hi jocelyn,
    Thank you very much

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Hi!
    I'm glad I could help. This a difficult question to answer. Perhaps it is of interest to demonstrate that only network size is related to performance, but ultimately it depends on your theory and your hypotheses. Could you explain this difference? Do you have extra information to support that claim? Welcome to the world of academic writing. Convince me! :)

  • @ruiwenkoh963
    @ruiwenkoh963 11 років тому

    Hi Jocelyn,
    this is a very good video. However, following Justin question, could I ask if the procedure for bootstrapping is the same when there are 3 levels of IV. My independent variable is level of helpfulness with 3 different level. My mediator is negative affect and there is a curvilinear trend. Will this method still work?

  • @justingarber7992
    @justingarber7992 11 років тому

    Hi Jocelyn,
    Your explanation was very clear and understandable! Much appreciated. I am currently in the process of determining what meditational analyses to use for my dissertation. My independent variable is racial identification. I plan to incorporate three racial groups. Is bootstrapping still applicable when utilizing 3 groups?
    Thanks again for the video!

  • @nicolapetrocchi6440
    @nicolapetrocchi6440 10 років тому

    Thank you very much for this amazing video!!!!!!!!!!!

  • @abdurahmanaliye2616
    @abdurahmanaliye2616 10 років тому +1

    Jocelyn thank you very much for the video. I am using multiple IVs, one mediator and 1 DV, can I treat each IV-M-DV as separate simple mediation?

    • @JoceOnFire
      @JoceOnFire  10 років тому +1

      HI! Thank you for your question. There is nothing preventing you from testing three different models, but my preference would be a model including all three independent variables simultaneously, especially if they are correlated. This approach could be tested using path analysis or Structural Equation Modeling with more advanced statistical packages such as AMOS, Lisrel, or EQS.

    • @amalaokpalanze9772
      @amalaokpalanze9772 10 років тому

      hi Abdulrahman, i also have a model that is like your. with 2 IV, IM and IDV. please how did you eventually do your analysis?

  • @JoceOnFire
    @JoceOnFire  11 років тому

    You are very welcome!

  • @francescotomaselli7853
    @francescotomaselli7853 10 років тому

    outstanding job, thanks. keep up the good work!

  • @hm3580
    @hm3580 10 років тому

    simply you are the best!!!!

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Hi,
    The value 0 is included in the interval -.0057; .1556, therefore the indirect effect is not significant.

  • @mustafaoztx
    @mustafaoztx 11 років тому

    Great video many thanks

  • @RyCrisp86
    @RyCrisp86 10 років тому

    Thank you, thank you, thank you!

    • @JoceOnFire
      @JoceOnFire  10 років тому

      You are more than welcome!

  • @oanatube
    @oanatube 11 років тому

    what if c path is not significant? (p>.05)

  • @russianrpincess
    @russianrpincess 10 років тому

    helpful lesson! thank you!

  • @carmenmejia8783
    @carmenmejia8783 10 років тому

    Any idea on how to do it with categorical?? with dummies is not working.. and i don't know why

  • @alyssasinger6582
    @alyssasinger6582 10 років тому

    Hi, great video. You say to bootstrap to 5000. Why? What literature suggests this. I'm looking for a source, thanks :)

    • @JoceOnFire
      @JoceOnFire  10 років тому +1

      Hi Alyssa,
      I would suggest you look into the following reference:
      Preacher, K. J., & Hayes, A. F. (2008). Asymptotic and resampling strategies for assessing and comparing indirect effects in multiple mediator models. Behavior research methods, 40(3), 879-891.

    • @alyssasinger6582
      @alyssasinger6582 10 років тому

      Jocelyn Bélanger Thanks!

  • @sylviakalindi5534
    @sylviakalindi5534 9 років тому

    So helpful! Thanks:)

  • @mahdiidham2
    @mahdiidham2 10 років тому

    could i use 90% interval instead of 95%. the C' path would be significant in that case. i mean 90& of accuracy for a small sample of 125 is good isnt it?

    • @JoceOnFire
      @JoceOnFire  10 років тому

      Hi Mahdi,
      You could use a 90% interval instead of a 95% one. It's still pretty good. However, conventionally, scientific publication (at least in Psychology) requires a 95% interval.

    • @mahdiidham2
      @mahdiidham2 10 років тому

      Dear Jocelyn,
      Thanks for the reply. which result is more accurate? results obtained from macros or hierarchical regression?

    • @JoceOnFire
      @JoceOnFire  10 років тому

      Bootstrapping results from macros are more accurate because they correct for bias.

    • @mahdiidham2
      @mahdiidham2 10 років тому

      Thanks

  • @JoceOnFire
    @JoceOnFire  11 років тому

    The betas from the indirect dialog and standard regression analyses in SPSS should be identical. I suspect you have missing values and that your regression analyses have different degrees of freedom.

  • @julienlamda9771
    @julienlamda9771 10 років тому

    Thanks a lot mate !!!

  • @seanicusvideo
    @seanicusvideo 10 років тому

    at 6:30 you say "unstandardized Beta coefficients" don't you mean "standardized" ? thanks!

    • @JoceOnFire
      @JoceOnFire  10 років тому

      Hi Sean,
      Thanks for your comment. The betas are unstandardized, unless you centered your variables before running the analyses.

  • @tkfdls0326
    @tkfdls0326 9 років тому

    thank you!!

  • @JoceOnFire
    @JoceOnFire  11 років тому

    Re: Hierarchical Regression: Challenge Accepted!

  • @ankithac
    @ankithac 10 років тому

    Many Thanks for your work it was really useful. Will contact if I need your help in the process.
    KRs.