The Kruskal-Wallis Test

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  • เผยแพร่เมื่อ 6 ก.ค. 2024
  • statisticslectures.com

ความคิดเห็น • 97

  • @aureliohess9349
    @aureliohess9349 7 ปีที่แล้ว +10

    Dear teacher, it was a wonderful explanation. Very clear and didactic. Thank you very much.

  • @anandakrishnan844
    @anandakrishnan844 5 ปีที่แล้ว +2

    This is just so clear and beautifully explained.

  • @rukhsanazaidi629
    @rukhsanazaidi629 7 ปีที่แล้ว +7

    You are amazing. Seriously. Such an amazing presentation. So clearly explained. Thanks so much.

  • @SuhasBajgurMD
    @SuhasBajgurMD 12 ปีที่แล้ว +4

    I really like the way you simplify the process into numerous steps. Now, I know what exactly is the logic behind those calculations when I use STATA. Thank you very much :)

  • @joanwaithera7485
    @joanwaithera7485 3 ปีที่แล้ว

    I love this channel, thank you❤

  • @anandakrishnan844
    @anandakrishnan844 5 ปีที่แล้ว +1

    I regret not finding this channel before.

  • @kareenkk356
    @kareenkk356 2 ปีที่แล้ว

    I watched many videos and read many sites this tutorial only made it clear what is df and h statistic value. Thank you very much.

  • @onlyyouareworthy
    @onlyyouareworthy 7 ปีที่แล้ว +1

    Brilliant explanation man. Really well done.

  • @sudhak8073
    @sudhak8073 7 ปีที่แล้ว +2

    Excellent presentation. Thank you....

  • @marcianasedentario7981
    @marcianasedentario7981 2 ปีที่แล้ว

    It' helps a lot to me as a beginner.
    Thank you very much for imparting and sharing your knowledge ♥️

  • @patte7k
    @patte7k 12 ปีที่แล้ว

    Great work!!!!

  • @fmwan1
    @fmwan1 7 ปีที่แล้ว +1

    Lovely, thank you! 😊

  • @lanzcordero2132
    @lanzcordero2132 3 ปีที่แล้ว

    this is actually very clear! Kudos!

  • @yungeodubbleg
    @yungeodubbleg 9 ปีที่แล้ว

    Video of the year

  • @rohankoroth2410
    @rohankoroth2410 3 หลายเดือนก่อน

    Thank you very much for the easy and wonderful explanation

  • @dylanparker130
    @dylanparker130 6 ปีที่แล้ว +1

    thank you so much - this helped a lot

  • @ceriamargareta8117
    @ceriamargareta8117 ปีที่แล้ว

    Thank you so much❤

  • @ginalynmostrales3145
    @ginalynmostrales3145 2 ปีที่แล้ว

    Wow, very brief and concise... My thanks

  • @AGaneshKumar73
    @AGaneshKumar73 9 ปีที่แล้ว +1

    Really very useful and thanks a lot..!

  • @surajisenanayake4345
    @surajisenanayake4345 2 ปีที่แล้ว

    Very clear. Thank you.

  • @faizaalee353
    @faizaalee353 5 ปีที่แล้ว

    so well explained GOD bless you

  • @mroosie7488
    @mroosie7488 4 ปีที่แล้ว

    Great video

  • @vismayadinesh745
    @vismayadinesh745 6 ปีที่แล้ว +1

    thank you for your lecture......

  • @siddharthmohansingh6065
    @siddharthmohansingh6065 3 ปีที่แล้ว

    Thank You Sir !

  • @sasohataba1
    @sasohataba1 11 ปีที่แล้ว

    رااااااااااااااااااااااااااااااائع جدا ...............شكرا

  • @tinalovesboston
    @tinalovesboston 12 ปีที่แล้ว +1

    Thank you for your fast reply. I realized my error- I was averaging the wrong column for the mean ranking so I had rank values that were lower than what they should have been. I was trying to compare the responses for the three different groups, but I'm thinking the one-way ANOVA is the best test. Thanks!

  • @mustafapoison6546
    @mustafapoison6546 ปีที่แล้ว

    perfectly done

  • @wasafisafi612
    @wasafisafi612 3 ปีที่แล้ว

    Thank you for the explanation

  • @SNIPE263
    @SNIPE263 3 ปีที่แล้ว

    nice and clear. Thanks!

  • @autriliarinella
    @autriliarinella 8 ปีที่แล้ว +1

    thanks a lot!

  • @parithimathi
    @parithimathi ปีที่แล้ว

    நன்றி. எளிதாகப் புரிந்தது.

  • @selaromnatsirt3949
    @selaromnatsirt3949 5 ปีที่แล้ว +1

    great help!

  • @Siwsonvirusman
    @Siwsonvirusman 9 ปีที่แล้ว

    Thanks!

  • @soninikul
    @soninikul 10 ปีที่แล้ว +1

    thanks a lot

  • @chuyuri3776
    @chuyuri3776 8 ปีที่แล้ว +1

    u helped me a lot!!!1

  • @xitsEHIMEx
    @xitsEHIMEx 11 ปีที่แล้ว +3

    What to you do if participants have the same number in each condition? How would you rank it

  • @jbvcxtr3056
    @jbvcxtr3056 4 ปีที่แล้ว +2

    What happens with the ranks if two numbers are the same, for example you have three 9's. How do you rank them?

  • @shalamandy10
    @shalamandy10 6 ปีที่แล้ว +1

    thanks

  • @roseb2105
    @roseb2105 6 ปีที่แล้ว

    what does the h test statistic mean exactly? why do we choose this formula? So let me get this straight my conclusion in this case would tell me me of some difference between my samples and the chi values tell me the probablity of having some number difference between my samples? I understand how to calculate the formula but how is it derived i dont want to just memorize it?

  • @Scynikk
    @Scynikk 10 ปีที่แล้ว +28

    I sleep during lectures and my professor is brain dead. Thanks a lot for the help.

    • @muhammadumair7781
      @muhammadumair7781 5 ปีที่แล้ว +6

      Respect Teachers Plz.

    • @danieleatzeni3400
      @danieleatzeni3400 3 ปีที่แล้ว +3

      @@muhammadumair7781 when they deserve respect, they are respected. Respect is not granted, is obtained through competence.

  • @tamerlanyusifov
    @tamerlanyusifov 3 ปีที่แล้ว

    Thank you for the video, very clear explanation, but there is one thing that I do not really understand. Why are we using Chi-Square distribution in this question?

  • @mansoorehjami7493
    @mansoorehjami7493 7 ปีที่แล้ว

    Perfect explanation.tnx

  • @minshugarg8166
    @minshugarg8166 11 ปีที่แล้ว +1

    Actually I have a question sir. I understood everything in the video but what will we do if we have tied ranks?
    thanks sir

  • @MrStefan135
    @MrStefan135 11 ปีที่แล้ว

    How would you put the formula on the calculator? It doesn't match your answer for the test statistic

  • @tinalovesboston
    @tinalovesboston 12 ปีที่แล้ว

    P.S. The reason why I was used this test initially was due to the Likert Scale. I read that using a one-way ANOVA isn't a good idea for scores ranging from 1-5, 1=strongly disagree, 5=strongly agree. Thanks again!

  • @WA-hq6ls
    @WA-hq6ls 3 ปีที่แล้ว

    good enough

  • @ahmedisse7641
    @ahmedisse7641 3 ปีที่แล้ว

    Thank you sir..
    But If have more than one sig. Value, should I do the average?

  • @vkys4594
    @vkys4594 10 ปีที่แล้ว

    please tell me how to code semantic differential scale in SPSS

  • @aregahaile707
    @aregahaile707 11 ปีที่แล้ว

    hi dear how are you doing?
    Could Friedman's test be applied to data from a one-way layout in which there are the same ,n, of observations from each of k treatments? Explain.
    Should Friedman's test be applied to such data? Explain.

  • @Draven.G
    @Draven.G 8 ปีที่แล้ว +1

    Which test can i use in case i need to use a non-parametric two way ANOVA? From what i understand, Kruskal-Wallis test is the non-parametric alternative for one way ANOVA

    • @woodchuk1
      @woodchuk1 8 ปีที่แล้ว

      Assuming that you have two way ANOVA with replication (where each combination of the two factors has more than one data point), and that all combinations have the same number of elements (that is, the ANOVA is balanced) and that this number is at least 5, you can use a test called the Schierer Ray Hare test as a nonparametric alternative to two way ANOVA. Reply back to me if you want the details.

  • @MJ-ye7dd
    @MJ-ye7dd 2 ปีที่แล้ว

    Why is the second table different form the first one?

  • @rc823
    @rc823 2 ปีที่แล้ว

    Hello guys,
    where can i find the Table with alpha and df online ? Does anyone have a link for me ?:) I need the source from the table for my excercise :) Thanks

  • @aregahaile707
    @aregahaile707 11 ปีที่แล้ว +1

    Show that maximum value of Friedman test statistic, s, is Smax=n(k-1)

  • @pranjalnath6850
    @pranjalnath6850 6 ปีที่แล้ว

    Thnx

  • @mikezimmer999
    @mikezimmer999 12 ปีที่แล้ว +1

    Hello. Excellent video! Question for you: In the formula for 'h' there was a numeric value of 3. Is this because there are 3 groups? In other words, if I have two groups (say, males and females) rather than 3, would I use 2 in the formula? Thanks! Mike

    • @woodchuk1
      @woodchuk1 7 ปีที่แล้ว

      Michael Zimmer No, that 3 is a constant, as is the 12 in the numerator of the fraction on the left hand side.

  • @tinalovesboston
    @tinalovesboston 12 ปีที่แล้ว

    I am analyzing survey scores for three questions using a Likert Scale (1=Strongly disagree to 5=Strongly agree) for three independent groups. Unfortunately, here is the breakdown for the first question:
    Score # Respones
    1 0
    2 0
    3 1
    4 21
    5 64
    As a result, I have only 3 ranks, low in value, yielding a negative H value. Am I doing the right test?

  • @aidan7646
    @aidan7646 2 ปีที่แล้ว

    What if when youre ranking you have lots of the same values?

  • @steven_grande
    @steven_grande 11 ปีที่แล้ว

    This is actually exactly what I want to do, how to do it on excel?

  • @cionasha-ked6907
    @cionasha-ked6907 3 ปีที่แล้ว

    what happens if I have different sample sizes?

  • @Jonpaulim
    @Jonpaulim 3 ปีที่แล้ว

    Hi great video I have subscribe can I ask a question please

  • @jamaecajalata7220
    @jamaecajalata7220 5 ปีที่แล้ว

    😍😍😍😍

  • @aravindssingapore4327
    @aravindssingapore4327 4 ปีที่แล้ว

    Kruskal Wallis sounds like a Pokémon's name.

  • @MegaMasturbator
    @MegaMasturbator 10 ปีที่แล้ว +1

    So it's always -3 before the (N+1), in the test stat.?

    • @qa1030
      @qa1030 9 ปีที่แล้ว

      MegaMasturbator yes

  • @sjornlim5301
    @sjornlim5301 9 ปีที่แล้ว +1

    how to find critical level

  • @neillpatterson
    @neillpatterson 12 ปีที่แล้ว

    You ranked the data but then never used the results of that. Since you are doing a chi-squared test, are you supposed to subtract the actual data from the ordinal rank and square that quantity?

  • @beckyb8929
    @beckyb8929 2 ปีที่แล้ว

    I watched this video without watching anything else, so where does the 12 come from on the last equation (H=etc)? Otherwise is clear. thank you

    • @woodchuk1
      @woodchuk1 ปีที่แล้ว

      I believe the 12 comes from the formula for calculating the variance of a uniform distribution, of which a series of rankings would be an example.

  • @kiransuz8226
    @kiransuz8226 3 ปีที่แล้ว

    Please do write down your source also

  • @neillpatterson
    @neillpatterson 12 ปีที่แล้ว

    @statslectures
    OK nevermind, I missed something you said. At 3:10 you say that you replace the data in your original table with the ranks. That's what I was missing, hence my misinformed comment.

  • @PhilipADonahue
    @PhilipADonahue 9 ปีที่แล้ว +2

    I have 24 as my N, and (48sq/8+32sq/8+27sq/8) (the last part is -75).
    After doing this equation I come up with -64.8575 as my H answer.
    It does not seem right that it should be negative.
    Any ideas?

    • @woodchuk1
      @woodchuk1 8 ปีที่แล้ว +1

      The sum of your ranks must be wrong...if you have 24 scores, the left side of the KW statistic (12/(24*25)) simplifies to 1/50. You would subtract 75 from the end, as you have done. If each group has 8 values, your denominators are correct. The only other part is the numerators...check your ranks again to make sure the sums are correct. They're too low if you're getting a negative result.

    • @woodchuk1
      @woodchuk1 8 ปีที่แล้ว

      +woodchuk1 The sums of your ranks should be equal to (1+2+3+...+24), or 300. So the numerators for each group should add to give 300.

  • @MIZRAIM1984
    @MIZRAIM1984 4 ปีที่แล้ว

    The tables for H values in respect to K-W test look different.

    • @jm6610
      @jm6610 4 ปีที่แล้ว

      I was thinking the same. The alpha = 0.01 column looks different.

  • @kinjaws9606
    @kinjaws9606 6 ปีที่แล้ว

    Quick question (URGENT), in the conclusion you say (2, N=18), p>.05: what is the "2" reffering to, and why p>.05?? Thanks

    • @woodchuk1
      @woodchuk1 6 ปีที่แล้ว

      I've deleted my previous replies since I screwed up...I was using the F statistic for the KW test when I shouldn't have. My error, sorry. The KW test uses the chi-square distribution, which has only one degree of freedom, equal to the number of groups minus 1. So since we have three groups here, we use 2 degrees of freedom in the chi-square distribution, not the F distribution. At an alpha of 0.05, our critical value is 5.991, and since our chi-square value of 2.854 falls short of the critical value, our test statistic cuts off an area greater than 5% on the right side of the curve. So our p value is greater than 0.05 and our value is not significant. The 18 here just refers to the total number of observations, but it's strictly not needed, since we don't have two separate degrees of freedom like we do in the F distribution. All we need for chi-square is the number of groups minus 1. Sorry for the mixup!

  • @mycollection5935
    @mycollection5935 8 ปีที่แล้ว +1

    is it possible that the group 1 has 6,6,6,6,6,6,6,8,6,66,8,6 and group 2 8,8,8,8,8,8,6,8,8,8 and group 3 10,10,8,10,10,10,8,10....how can i rank these? oh my g....pls help

    • @woodchuk1
      @woodchuk1 8 ปีที่แล้ว +1

      First, let's assume that the 66 was meant to be two 6's. Then, I get that we have 12 6's, 13 8's, and 6 10's. If the 6's were all distinct, they would occupy ranks 1-12 in numerical order. Since they are identical, we assign each 6 the average rank of 1-12 (1+2+3+...+12, all divided by 12), which is 6.5. Likewise, the 8's would occupy ranks 13-25 if distinct; averaging as before, I get 19 to be used as the rank for all the 8's. Lastly, the 10's would occupy ranks 26-31, so they would all receive an average rank of 28.5. Run the KW test using these ranks, and divide the result by 0.864919 as a correction factor for the extensive ties. That's your answer. If you want more info, message me back.

    • @woodchuk1
      @woodchuk1 8 ปีที่แล้ว +1

      +woodchuk1 The correction factor should be 0.861895 instead...sorry for the error! It makes no difference in this case, as the correction factor always increases the value of the test statistic, which was already far over the critical value before the correction in this case. So your conclusion would have been the same either way.

    • @autriliarinella
      @autriliarinella 8 ปีที่แล้ว +1

      well in my opinion if you have the same score perhaps you can do this:
      You know in the group one 6 is the smallest score (since the biggest is 8), then it should be put before the 8 score. The problem is you have no idea whats the rank for each 6 score since there are eleven of 6 score, then to know the exact rank all you have to do first is divide the first and second rank so you can get the rank for each 6 score.
      Example:
      6,6,8,7----> supposed to have 4 ranks, but oops we have the same score. But 6 is the smallest, so it must be put in the first and second rank before 7 and 8. But whats the exact rank for them?
      (1+2)/2: 1,5.
      So the rank for each of them is 1.5
      Since you have more than two of 6 score then you have to do this several times.

  • @taylortalarico2729
    @taylortalarico2729 7 ปีที่แล้ว +1

    can anyone explain to me how to solve the equation? how do they get 2.84??

    • @woodchuk1
      @woodchuk1 7 ปีที่แล้ว +1

      39^2/6 = 253.5
      65^2/6 = 704.167
      67^2/6 = 748.167
      253.5 + 704.167 + 748.167 = 1705.834
      1705.834 * 12 = 20470.008
      20470.008/(18*19) = 59.854
      59.854 - (3)(18 + 1) = 2.854

    • @brandonpaquette1762
      @brandonpaquette1762 5 ปีที่แล้ว

      woodchuk1 I love you so much

  • @meeteshdhulapkar
    @meeteshdhulapkar ปีที่แล้ว

    Sir thank you:
    Translated by google

  • @thetinkertech
    @thetinkertech 3 ปีที่แล้ว

    At 5:11 how is N=18? Wasn't it 6?

    • @ellizabtty
      @ellizabtty ปีที่แล้ว

      That’s a big N, so you’re multiplying the 3 samples that’s 6*6*6=18 since it’s big N which means total of all 3 Ns. Small n is 6

  • @montymondal3709
    @montymondal3709 4 ปีที่แล้ว

    Excuse me your formula is not visible due to your subtitle.

  • @patelsourabh7291
    @patelsourabh7291 4 ปีที่แล้ว

    Bro the smallest value is one

  • @rupeshraut727
    @rupeshraut727 3 ปีที่แล้ว

    V

  • @rupeshraut727
    @rupeshraut727 3 ปีที่แล้ว

    H

  • @rupeshraut727
    @rupeshraut727 3 ปีที่แล้ว

    H

  • @rupeshraut727
    @rupeshraut727 3 ปีที่แล้ว

    H