An Introduction to the Continuous Uniform Distribution

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  • Опубліковано 6 жов 2024
  • A brief introduction to the (continuous) uniform distribution. I discuss its pdf, median, mean, and variance. I also work through an example of finding a probability and a percentile. I don't do any integration in this video.
    (This video contains a (small) typo at 6:22, that I corrected with an annotation. A new version of this video with the mistake corrected can be found at • Introduction to the Co... .)

КОМЕНТАРІ • 178

  • @Leeannannaeel
    @Leeannannaeel 7 років тому +141

    I never comment on anything, but this is so excellent. Immediately understood a concept I have been trying to understand for twelve hours.

    • @jbstatistics
      @jbstatistics  7 років тому +5

      I'm glad to be of help!

    • @mulchdiggums3016
      @mulchdiggums3016 5 років тому +1

      You and me both! This makes SO much sense when explained properly

    • @rahulkatara6650
      @rahulkatara6650 4 роки тому

      Do you get the logic of formula of Variance?

  • @jbstatistics
    @jbstatistics  11 років тому +2

    The 20th percentile is the value of the variable that yields an area to the left of 0.20. The area to the left is the area of a rectangle with a base of a - 200, and a height of f(x). This means that (a-200)f(x) = 0.20. (d-c)f(x) = 1, since d and c are given as the endpoints.

  • @CatholicSeoul
    @CatholicSeoul 6 років тому +44

    Good instructors are usually found on UA-cam and not in classrooms! Thanks!

    • @jbstatistics
      @jbstatistics  6 років тому +8

      My main gig is in the classroom :)

  • @jbstatistics
    @jbstatistics  11 років тому +14

    Thanks for the feedback and compliment. For a continuous random variable, the pth percentile is the value of the variable that has p% of the area to the left. In the video I say "the 20th percentile is the value of the variable such that the area to the left is 0.2, or 20%". I'm not sure how much clearer I could make that, without going off on a tangent about the meaning of percentiles. At this point in a stats course students have usually been introduced to the concept of percentiles already.

  • @jbstatistics
    @jbstatistics  11 років тому +3

    The expected value is just the mean, which is given in the video (the midpoint between the minimum and maximum). To use calculus to show that, you would find the definite integral of x*1/(d-c) dx, between c and d.

  • @sheriffpina4102
    @sheriffpina4102 4 роки тому +2

    I have a professor that truly doesn’t understand the profession and subject he has selected. His poor choice has me searching through UA-cam videos for an idea to get started on my exams/homeworks. This video has helped me tremendously, you’ve earned yourself a like and a new subscriber!

  • @leneescott
    @leneescott 8 років тому +9

    You saved my life! I am taking Statistics online this semester so I have to learn everything on my own. But I was never one from learning straight from a book. I was so confused and getting frustrated. This video is a life saver! Thank you!

    • @jbstatistics
      @jbstatistics  8 років тому +2

      You are very welcome. I'm glad I could help!

  • @angelachanel9503
    @angelachanel9503 4 роки тому +2

    almost 8 years later.. and I also think this is brilliant! Thank you!

  • @lelelanaa2500
    @lelelanaa2500 10 років тому +2

    Whenever I have to watch Stats videos...always check for this channel first!!! Best channel for Statistics!! Would recommend to anyone!

  • @MissSilanda
    @MissSilanda 8 років тому +17

    If my professor explained it this well I wouldn't be here.. Thank you so much😀👌 it makes much more sense now💃

  • @mustahidhasan5098
    @mustahidhasan5098 5 років тому +2

    Thanks for your lecture.That seems these videos were made 7 years ago when i was just a kid, but still helpful for me in this stage.Again thank u for clearing the basic concept

    • @jbstatistics
      @jbstatistics  5 років тому +2

      Thanks for the kind words, and I'm very glad I could help. I built them to stand the test of time :) The basic concepts of statistics and the underlying mathematics stay the same of course, but I also chose examples that would't look out of place 50 years from now.

  • @abdullahshahid9051
    @abdullahshahid9051 2 роки тому

    What i like about your videos are that they focus on understanding and intuition; not tricks on how to compute. Great job!

    • @jbstatistics
      @jbstatistics  2 роки тому

      Thanks so much! I'm always happy to hear this type of compliment as that's what I always shoot for. I teach statistics here, not tricks and tips for answering statistics questions.

  • @lindaren9467
    @lindaren9467 4 роки тому +1

    I have been struggling with my stat studies over a week now and so grateful for all your videos and they really help me a great deal. So amazing how you can make complicated things so simple and understandable. Also nice to watch your videos without having to experience annoying commercials. Thanks!

  • @rasikmohamed500
    @rasikmohamed500 2 роки тому +2

    Woww..Short and crispy..Watching this 9years old video for my Data science introductory....Maths have no versions..Big Thanks to god ❤️

    • @jbstatistics
      @jbstatistics  2 роки тому +1

      I'm glad to be of help! I tried to build them to last the test of time.

  • @rahulvarma7257
    @rahulvarma7257 4 роки тому +3

    wonderful explanation sir. you’re way of teaching is very much comfortable even for average students. keep it up 👏👏

  • @shareemrasyidi9948
    @shareemrasyidi9948 3 роки тому

    Iam really struggling hard on statistics because of online class being very ineffective, glad this channel can really explain it pretty well and easy to understand

  • @tahamagdy4932
    @tahamagdy4932 7 років тому +4

    Just saved my life.
    I would give you a hug.

    • @jbstatistics
      @jbstatistics  7 років тому +3

      I would take one! I'm glad to be of help.

  • @Akshay-lj4fh
    @Akshay-lj4fh 6 років тому

    Great job!!! Very useful videos.. I was panicking till now; I open this channel and keep watching videos in loop and I find that I am done!!!! Superb!!!!!!

    • @jbstatistics
      @jbstatistics  6 років тому

      I'm glad you found my videos helpful!

  • @goodknight3072
    @goodknight3072 5 років тому

    My teacher used some terrible quality video for gamma and exponential distributions. I was wondering why until I noticed you didn't have a video on it (atleast that I could find). So glad to be back watching your videos again. Thanks again for teaching me stats!

  • @jbstatistics
    @jbstatistics  11 років тому +1

    You're very welcome Kary! Je t'en prie!

  • @markgao5963
    @markgao5963 7 років тому +45

    When it comes to the night before my pstat final.

  • @jimmybandme
    @jimmybandme 9 років тому +2

    Great job man, tons of respect for you. Thank you for helping all of us non-stats kids out, keep up the amazing job :)

    • @jbstatistics
      @jbstatistics  9 років тому +2

      +jimmybandme You are very welcome, and thanks for the compliment!

  • @shridz_
    @shridz_ 2 роки тому

    Your videos are brief and to the point. I really love them. However I want to point out something.
    I believe that for x in (c,d), the values c and d are not inclusive, hence we should write c < x < d.
    This is also because the c.d.f. of X is not differentiable at points x = c and x=d so the p.d.f. f(x) doesn't exist at these points.

  • @rehabmadkhali6649
    @rehabmadkhali6649 9 років тому +9

    it's so clear to understand ....thank you

  • @60daan
    @60daan 4 роки тому

    Thanks! learned more in this video than in an entire lecture from my "teacher" !

  • @christinenalwoga6008
    @christinenalwoga6008 3 роки тому

    Wow, your work is really of much help than you could even imagine

  • @jbstatistics
    @jbstatistics  11 років тому

    You are very welcome Jubayer.

  • @tlhomotsemoteme2423
    @tlhomotsemoteme2423 6 років тому

    Thank you so much, I really appreciate your work. I understand better than before when I watch your videos. Thank you.

  • @jbstatistics
    @jbstatistics  11 років тому +1

    Yikes! Thanks for letting me know -- I hadn't noticed that. I'll have to fix that up.

  • @Anu_Tuvs
    @Anu_Tuvs 4 роки тому

    I am beyond grateful for your stats videos! THANK YOU VERY MUCH!

  • @angie9zhou
    @angie9zhou 5 років тому

    easy to understand. easy sample. good job. hope to see the normal distribution video

  • @0301850
    @0301850 11 років тому

    Best video i've ever watched for the uniform distribution

  • @saikrishna2000
    @saikrishna2000 5 років тому

    Your channel is just awesome! You clearly explain each and every concept, and am happy for that. You just gained another sub. Cheers!

  • @maurogg9682
    @maurogg9682 8 років тому +1

    Great Job .These video series are awesome . Very well explained and expose . Thanks a lot men

  • @nernaykumar8334
    @nernaykumar8334 3 роки тому

    One of the best explanations !!!!

  • @ishanpandey4300
    @ishanpandey4300 5 років тому

    This was honestly so useful. I was going crazy over this. Thank you so much :)

  • @MisterBinx
    @MisterBinx 3 роки тому +1

    OMG why is this so simple here. I was thinking something completely different.

  • @abdallahgamal5092
    @abdallahgamal5092 6 років тому

    Your videos are amazing i hope you continue them by making videos for the joint disturbutions and the covariance and the correlations thank you so much

    • @jbstatistics
      @jbstatistics  6 років тому +1

      Thanks for the compliment! I'll be making new videos in the new year, and will try to get to your suggestions (they are commonly suggested topics). All the best.

  • @smartcupoftea8972
    @smartcupoftea8972 6 років тому

    Very well done. Easy to understand and easy to follow. Thank you!

  • @duytran-hg4cl
    @duytran-hg4cl 4 роки тому

    thank u so much, it still works until today !

  • @Hellstorm79
    @Hellstorm79 11 років тому

    This is an awesome video, super helpful. Right up until the percentile part. That needs to be greatly clarified. How you actually got the .2 is not clear at all.

  • @DarrellBarnes
    @DarrellBarnes 5 років тому

    Broken down for a simple guy like me....thanks!

  • @sharminmanocha3938
    @sharminmanocha3938 5 років тому

    This helped me understand so much better, thank you !!

  • @ICOD73
    @ICOD73 10 років тому

    Thx for this clear explanation but I am wondering why you didn't mention the moment generating function also. It is useful in finding the mean and variance.

    • @jbstatistics
      @jbstatistics  10 років тому

      To this point, my videos have been pitched at the level of an applied statistics course to students not majoring in statistics. While moment generating functions are certainly useful, they are not something that is typically discussed in this type of introductory statistics course. Cheers.

  • @jideenitan
    @jideenitan 3 роки тому

    Thank you so much.
    I've learned so much on probability distribution thank to you.

  • @mohammedyousri5826
    @mohammedyousri5826 4 роки тому

    very good explanation
    do not stop

  • @psudhir4336
    @psudhir4336 4 роки тому

    Excellent explanation, but one thing, you could have shown the equivalent way of doing with integration too i.e integration of f(x) dx with limits 230 to 250, many places I see the f(x) as 1 for uniform distribution ..how that rho(x) is calulated

  • @kinleyyangzom5318
    @kinleyyangzom5318 8 років тому +1

    thank you!! all the videos i watched of yours' were very helpful!!!

  • @DarkZoneGamingMain
    @DarkZoneGamingMain 10 років тому

    Your videos helped me immensely man, I can't thank you enough! I have done all my practice questions for the entire year but there is one type of question I can wrap around, its slightly different in its format don't know if you could take a look at it:
    Consider a uniform distribution between 0 and b where b is unknown, i.e. x~ U(0, b)
    i) A single sample is observed with value x=5.0. What is the maximum likelihood (ML) estimate for the parameter b?
    How would this type of question be done? Im not sure what is maximum likelihood..

  • @bijoudeaux1
    @bijoudeaux1 11 років тому

    Another great video but I don't understand why for the percentile part you used: (a-200) * 1/50= 0.2. According to the info, the formula is d-c * f(x). In this case, why didn't you use 250 as d and the other c. That's where I am confused.

  • @josebernardosanchezetchega501
    @josebernardosanchezetchega501 10 років тому

    The best channel to learn statistics! Thanks man!

  • @LiveLoveLifewithRima
    @LiveLoveLifewithRima 5 років тому

    It's so clear to understand. Thank you

  • @aishamalik2282
    @aishamalik2282 3 роки тому

    Thanks for the video, i believe 6:51 is mathematically incorrect bij saying 0.2=210

  • @samikshamallaiya2924
    @samikshamallaiya2924 2 роки тому

    nicely well explained.thank you so much

  • @Brownlee314
    @Brownlee314 11 років тому

    Nice video!! (except that part in the percentile example where you wrote 0.2 = 210)

  • @kushaleshshetty
    @kushaleshshetty 2 роки тому

    Thank you so much for this excellent video..

  • @carlossolrac4396
    @carlossolrac4396 4 роки тому

    At 6:27 minutes you claim that 0.2 is equal to 210!!!! Please, make a correction; just add another line saying a = 200 + 0.2x50 = 210.

  • @leetran7123
    @leetran7123 3 роки тому +1

    Thank you very much, very helpful for me!

    • @jbstatistics
      @jbstatistics  3 роки тому +1

      You are very welcome! I'm glad to be of help!

  • @ryans.6273
    @ryans.6273 6 років тому +6

    My college stats professor is goddamn useless. Thanks for this

    • @TheDekramer
      @TheDekramer 3 роки тому

      i think were in the same boat lmao

  • @muratcan__22
    @muratcan__22 6 років тому

    Right choice for all the distribution types

    • @muratcan__22
      @muratcan__22 6 років тому

      There are some minor things that makes these videos special. For example when you say it is not a distribution unless we write the Random variables Xs and the probabilities. That sentence solidify the term distribution in minds of students like me who are just memorized the distrubition word but have never got the intuition of it

    • @jbstatistics
      @jbstatistics  6 років тому

      Thanks so much for the kind words! I'm very happy that my methods help you develop a better intuitive understanding of the topics!

  • @that_guy_in_a_bowtie4849
    @that_guy_in_a_bowtie4849 4 роки тому

    Why are the random people on the internet so much better at teaching concepts than people who have trained for atleast 4 years to do exactly that?

  • @Kevin-cy2dr
    @Kevin-cy2dr 5 років тому

    Is your statistics course enough for data science/machine learning?

  • @Once-Upon-A-Dime
    @Once-Upon-A-Dime 6 років тому

    Hello Professor, if the median and mean is 50% of the distribution, the formula should be (a-200)x1/50 = 50/100 *not* c+d/2 because 0 to C is least of the concern, I think it should be (d-c)/2... If you have time, please guide.

    • @jbstatistics
      @jbstatistics  6 років тому +2

      For the example in this video, the mean and median would lie halfway between 200 and 250. Solving for a in (a-200)*1/50 = 50/100 yields a = 225, and (200 + 250)/2 = 225. Either way we get the same (correct) result. (d-c)/2 = 25, which is the *distance* from either endpoint to the median, but is not the median.

    • @Once-Upon-A-Dime
      @Once-Upon-A-Dime 6 років тому +1

      jbstatistics Thank you sire, sorry to disturb for my silly calculation error.

  • @ASURAN24
    @ASURAN24 4 роки тому

    Hey man, you've got an error when you loosely used the equal sign. You should separately say a = 210 instead.

    • @jbstatistics
      @jbstatistics  4 роки тому

      Yes, thanks for pointing that out. Had a brain fart there. I've addressed that in the comments, and created an updated version without the error. I put in an annotation fix long ago, but I don't know if those things show up anymore.

  • @hamoody3
    @hamoody3 7 років тому

    20th percentile. why to the left not the right. Why a-200 not a-250?

  • @shreyashankar6773
    @shreyashankar6773 8 років тому

    this is brilliant, thank-you so very much

  • @antisocialbarbie1587
    @antisocialbarbie1587 Рік тому

    May the almighty bless you thank you so much

  • @DbzFighter02
    @DbzFighter02 11 років тому

    is there an expected value when using a uniform distribution

  • @Kushagra_Gupta
    @Kushagra_Gupta 4 роки тому

    what if c =0,d=1 then 1/(c-d) would be equal to 1 for every number

  • @jmoney9439
    @jmoney9439 5 років тому

    So how do you know that u need to take the left side area or the right side?

  • @ollod
    @ollod 6 років тому

    I have a problem of concept here. If the probability of getting f(x) = 1/50 for 200

    • @jbstatistics
      @jbstatistics  6 років тому +1

      This video discusses the *continuous* uniform distribution, where the random variable can take on an infinite number of possible values. You're thinking of a discrete uniform distribution, with 51 equally likely possibilities, but that's not the case here.

  • @IggyOVOXO
    @IggyOVOXO 7 років тому

    You are the real MVP

  • @yashjain1695
    @yashjain1695 11 місяців тому

    Question: for P(X>230) shouldnt it be 250-231 and not 230 since the minimum value x can take on is 231

    • @jbstatistics
      @jbstatistics  11 місяців тому

      It's a continuous distribution. P(X > 230) = P(X > 230.0000000000000000000000000...) In the example, X doesn't take on only whole number values, it takes on any value in the continuum between 200 and 250.

  • @olgaromazan5894
    @olgaromazan5894 6 років тому

    excellent explanation. thanks

  • @Rahul-oq7wc
    @Rahul-oq7wc 6 років тому

    taking value of (b-a)1 don’t that contradict f(x) RANGE?

    • @jbstatistics
      @jbstatistics  6 років тому

      For continuous distributions, the restrictions on f(x) are: 1) f(x) >= 0 everywhere, and 2) f(x) integrates to 1. The value of f(x) can be (and often is) greater than 1. This is not a problem, as the value of f(x) is not itself a probability, but is simply the height of the curve at point x.

    • @Rahul-oq7wc
      @Rahul-oq7wc 6 років тому

      thanks for the instant reply and correct me

  • @leandronapalinga536
    @leandronapalinga536 10 років тому

    do you have a video of the discrete uniform distribution?

  • @arlettemunoz3639
    @arlettemunoz3639 5 років тому

    what does f(x) represent in the context of a problem??

  • @bijoudeaux1
    @bijoudeaux1 11 років тому

    I looked at it again and was able to understand. (Y)

  • @rugvedkulkarni1593
    @rugvedkulkarni1593 4 роки тому

    What happens when you are looking for Greater than and including or lesser than and including a certain point?

    • @jbstatistics
      @jbstatistics  4 роки тому

      If X is any continuous random variable, and b is any constant, then P(X=b) = 0, and thus P(X>=b) = P(X > b) and P(X

    • @rugvedkulkarni1593
      @rugvedkulkarni1593 4 роки тому

      @@jbstatistics Thank you! This helped me a lot! :)

  • @kingsleyking6690
    @kingsleyking6690 9 років тому

    can the interval be negactive? e.g -1=1

  • @GOODBOY-vt1cf
    @GOODBOY-vt1cf 4 роки тому +1

    thank you so much

  • @yap9660
    @yap9660 5 років тому

    Why the area is equal to 1?

  • @ashrafal-warraquiy6614
    @ashrafal-warraquiy6614 3 роки тому

    why in variance we divide by 12 this is unclear.

  • @hesahesa5665
    @hesahesa5665 8 років тому

    شكرا لك افضل فيديو شفته
    thanks very much

  • @dawsonschwatz4102
    @dawsonschwatz4102 5 років тому

    He explains it so well, this video is saving my ass right now 😂

  • @nuhabinganem2854
    @nuhabinganem2854 10 років тому

    I should say thank you because its amazing explanation
    thank you so much

  • @Manas-co8wl
    @Manas-co8wl 3 роки тому

    Huh. Shouldn't this be taught before Normal Distribution?

    • @jbstatistics
      @jbstatistics  3 роки тому

      Yes, it's typically best to discuss this simple distribution before the normal distribution. Why the "huh"?

  • @afaf6478
    @afaf6478 7 років тому

    thanks! great explanation

  • @anvin5251
    @anvin5251 10 років тому

    V good explanation. Thanks a ton!

  • @the_teemo1
    @the_teemo1 5 років тому

    intuitively, what does f(x) actually mean?

    • @jbstatistics
      @jbstatistics  5 років тому +1

      There's no super easy and understandable explanation to that. The value of f(x) at x is the rate of change of the cumulative distribution function F(x) at x. Probably the easiest explanation is the rectangle approximation to the integral: for a small change in x (delta x, say), f(x)*delta x is approximately P(x < X < x + delta x).

  • @m.l.f.rilwana
    @m.l.f.rilwana 4 роки тому

    I have a question what if a is negative and b is positive value
    When applying to equation do I disregard the sign?

    • @jbstatistics
      @jbstatistics  4 роки тому +1

      No, leave the sign in. There are no issues with a being negative (or a and b being negative). The only restriction is that b > a.

    • @m.l.f.rilwana
      @m.l.f.rilwana 4 роки тому

      Ok thankyou

  • @raggihosni4030
    @raggihosni4030 5 років тому

    god bless you dude again!

  • @cemturanl250
    @cemturanl250 7 років тому

    Man you are great thank you very much

  • @str223
    @str223 5 років тому

    Thank you Sir.

  • @se1toku
    @se1toku 3 роки тому

    Nice video!

  • @vansikasingh3228
    @vansikasingh3228 4 роки тому

    Thank you so much!

  • @orkhanhasanov1922
    @orkhanhasanov1922 3 роки тому

    Perfdct explanation!

  • @em5506
    @em5506 5 років тому

    Thank You!!

  • @69sydney
    @69sydney 8 років тому +3

    4 people already failed

  • @SB_Roy_Vlogs
    @SB_Roy_Vlogs Рік тому

    wow...excellent