THANK YOU SO MUCH! I literally spent five hours reading articles and statistics pages that did no more than confuse me and watching your video was so nice and relaxing for me because not only were you clear but you were able to explain it with a useful example
I don't know why I was having so much trouble understanding this test with written direction but your video was very helpful to me. It presented the necessary info concisely and in a manner east to understand.
thanks Sir for explaining the topic in such a good manner 👍👍......it is in my MBA syllabus and I am thinking of learning in advance about this topic and after watching your video I can surely say I learned about the Mann Whitney U Test and it will be very helpful for me now to understand when college starts explaining about this topic
Thank you so much for posting these videos. I keep running into explanations with shortcuts because calculators usually do the work now, but I get stuck on the details. Wish I had you as a teacher in high school!
Thank you very much for your videos! By writing down the statistical tests it is easier to understand and you explain it very well, slowly and in a very clear way !
Thank you so much! I'm taking an online class, and they never mentioned how to do the ranking, so I've always been really confused at how the answer was gotten.
Amazing!! I am studying for the 6-sigma black belt exams and this made me understand the Mann Whitney U test. I have subscribed as your explanations even for the Kruskal-Wallis test was equally very clear!
Great explanation! my module provided an Excel spread sheet to do this, on which it said they expect us to also do it by hand but they didn't explained how. Thanks for the help!
Once again, thanks for the assist : ) This was an awesome and useful video for me. I am great with the parametric statistical methods, but one of the college students that I tutor had questions about non-parametric students. Great explanation!
Thank you for that immensely helpful video. I have a small clarification question. Let's say there are three scores that tie, does the procedure of calculating the average apply as well? That is, if you had three 2's among your scores, would each get rank 2 by (1+2+3)/3=2?
this video is excellent, thanks! I have a small sample size and R couldn't deal with all the tied values, was able to do it myself in 15 mins following this.
According to Wikipedia Ua+Ub should equal Na*Nb. in my data set i have 2 groups for a total of 126 responses. Na=67 Nb=59. Responses range between 0 and 10 in their value. Group A has: 17 responses of 0 ranked at 11.5 3 responses of 1 ranked at 26 4 responses of 2 ranked at 33 5 respoonses of 3 ranked at 44 6 responses of 4 ranked at 55.5 20 responses of 5 ranked at 78.5 2 responses of 6 ranked at 99 3 responses of 7 ranked at 103 2 responses of 8 ranked at 110 0 responses of 9 and 5 responses of 10 ranked at 120.5 Group B has 5 responses of 0 ranked at 11.5 4 responses of 1 ranked at 26 3 responses of 2 ranked at 33 10 responses of 3 ranked at 44 2 responses of 4 ranked at 55.5 18 responses of 5 ranked at 78.5 1 responses of 6 ranked at 99 2 responses of 7 ranked at 103 7 responses of 8 ranked at 110 0 responses of 9 and 7 responses of 10 ranked at 120.5 So I calculated my Ua and Ub and tried to check whether I did it right, However, when i add Ua and Ub i get 3985, whilst Na*Nb amounts to 3953. So i must be doing something wrong. I have no clue what. Does anyone have any clue what is going wrong?
Happens almost fail-proof. You calculate something wrong, and you know it is but not why... as soon as you start panicking and flailing around until you give up and ask others for help you see your mistake...., Mine was that i calculated the U's wrong. I did Ua= Ra-((Na(Nb+1)/2) instead of Ua=Ra-((Na(Na+1)/2)..... Aaaanyway thanks a bunch for the vid, also helped me alot. Cheers from the Netherlands!
The explanation was very clear, thank you for sharing it. I would like to make a suggestion - include a slightly more elaborate example that connects these numbers to the real world. In this case you mentioned that the numbers came from the results of two distinct treatments. For me it would be more helpful if that was accompanied by something like "The numbers you see correspond to the number of lesions that remained on a person's body after treatment was applied; thus we want to compare the lesion-healing effects of drug A and drug B". This would make the problem less abstract. Otherwise there is a chance that some people will be able to do the number-crunching, but struggle to come up with an answer when asked "so where can you apply this?".
Why is the U value being calculated differently in this example? The original paper by Mann-Whitney 1947 uses a different formula. You are also not the only professor I have seen using a different formula.
Two questions - 1. Why did you take U statistic instead of Z for comparing calculated and critical values ? 2. U statistic is calculated with the formulae : U1 = n1n2 + n1(n1+1)/2 - Sigma R U2 = n1n2 + n2(n2+1)/2 - Sigma R your formula for U-statistic is different. I could not find that in any statistic book or internet. All of them give the listed above formula. would appreciate if you could answer that. Thanks, Bhaskar
The formula is different, but the values calculated for U1 and U2 are just exchanged. This is because the above formula just subtracts the formula used in the video from n1n2. In the end while selecting the min(U1,U2) it wouldn’t matter if the values of U1 and U2 are exchanged. But still, I wonder why change the formula anyway.
Mr. Eugene if you are a class teacher and you conduct exams for two different classes but in the subject. mathematics two data is different in number one class is 32 and one class is 14. they are both skewed. con you please use this approach to compare the performances between theses classes?
i have been searching and looking for how to do this for five hours now... this finally helped. thank you. may i just ask one question? when you whipped out that paper, and where the columns met and you had to choose either 0.01 or 0.05. why did you choose 0.05?
iirc 0.05 is a significance value of 95%, 0.01 is 99% so if you want to be even more confident use 0.01 but most use 0.05. I could be wrong though as I am trying to remember all this from many years ago.
This is the day before my exam and let's just say you turned a 1hr class into 9 min! Thank You!!!
Day of exam💪💪
@@VaporyBeathow did it go
The best video I have found regarding the Mann Whitney U test! Thank you!
Once again, clear, right to the point, easy to understand, only 10 minutes. Thank you for your work!
I'm doing a Thesis for the Dentistry Degree in Italy and you saved me! God Bless You, man!
THANK YOU SO MUCH! I literally spent five hours reading articles and statistics pages that did no more than confuse me and watching your video was so nice and relaxing for me because not only were you clear but you were able to explain it with a useful example
Thank you so much! My exam is tomorrow and I just spent all day stressing over this and I am so glad I found this video!
You're a legend. I am embarrassed to say how long I spent trying to figure this out before i watched this video. Thank you.
My 1 hour tutorial that had no favorable outcome had been solved in 9 minutes. Thank you, great job.
I'm currently writing my dissertation and this was immensely helpful - THANK YOU!
U just turned a 2 and a half hour lesson into 9 mins and I learnt way faster thank you
I don't know why I was having so much trouble understanding this test with written direction but your video was very helpful to me. It presented the necessary info concisely and in a manner east to understand.
thanks Sir for explaining the topic in such a good manner 👍👍......it is in my MBA syllabus and I am thinking of learning in advance about this topic and after watching your video I can surely say I learned about the Mann Whitney U Test and it will be very helpful for me now to understand when college starts explaining about this topic
I don't have to perform it by hand but your explanation helped me understand what I'm "clicking" in Statistica. That was so helpful, thank you.
Thank you so much for posting these videos. I keep running into explanations with shortcuts because calculators usually do the work now, but I get stuck on the details. Wish I had you as a teacher in high school!
This man is out here saving lives.
Mr. O'Loughlin, you are my hero. Thank you so much!!
Thank you very much for your videos! By writing down the statistical tests it is easier to understand and you explain it very well, slowly and in a very clear way !
Thank you sir , this video has cleared all my doubts which my university teachers couldn't solved!
You just saved my classes bacon on their psychology coursework, Thank you!
The best video on RUclips for mann Whitney u test
Excellent work sir. Understood it in a single watch.
I'm taking Stats online and I only have my book to guide me step by step and this video helped so much! Thank you!
Thanx proffessor u save my life today bcz tomorrow I have exam but bcz of this video everything is fine now thank u so much😍
Thank you so much! I'm taking an online class, and they never mentioned how to do the ranking, so I've always been really confused at how the answer was gotten.
thank you so much for this. your video series is so clear and concise. you are a legend sir
Thanku so much! Tomorrow is my exam and your video is so helpful ❤
Amazing!! I am studying for the 6-sigma black belt exams and this made me understand the Mann Whitney U test. I have subscribed as your explanations even for the Kruskal-Wallis test was equally very clear!
Well done Eugene on another great video. Clear and concise as always. Please keep up the good work
I was confused about the last bit, thanks for clearing!
Thank you!!!! This video made everything sound so simple!! Saved my grade!!
Great explanation! my module provided an Excel spread sheet to do this, on which it said they expect us to also do it by hand but they didn't explained how. Thanks for the help!
You're the best sir. Take a bow.
Thank u for being a genuine life saver...like I can't even express how much you have just helped me THANKYOU!!!!
Once again, thanks for the assist : ) This was an awesome and useful video for me. I am great with the parametric statistical methods, but one of the college students that I tutor had questions about non-parametric students. Great explanation!
Thank you for that immensely helpful video. I have a small clarification question. Let's say there are three scores that tie, does the procedure of calculating the average apply as well? That is, if you had three 2's among your scores, would each get rank 2 by (1+2+3)/3=2?
Yes. 😊
I've got an exam after 4 days and thanks your video
Thanks a ton. Please keep making videos on stats and enlighten us through knowledge.
Watching this 1hr before exam :). Thx
This was extremely helpful! Very clear, simple, easy to understand explanation.
this video is excellent, thanks! I have a small sample size and R couldn't deal with all the tied values, was able to do it myself in 15 mins following this.
Thanks God I met your video! You're an ANGEL!!!
Amazing video. It's essentialy one of my statistic lectures in a fraction of the time.
Keep up the good work!
You are amazing! Best video for exams EVER! Thank you so so much!!!
Great video, everything is explained simple and steb by step. Thank you!
Great Sir, very simply you taught it, I felt like I learned it in a class.
Very simplified and well explained. Thank you
Thank you for your very clear and helpful explanation.
wow, i wish my stats teacher was as good at teaching as you are
You helped me to pass my exam .
Thanks a lot !
thanks so much my exam was is today and i missed the lectures on this saved me
Beautiful, instructive example sir!
this was super helpful!! thank you for taking your time to do this im so grateful!!!
I am finding your videos very helpful! Thank you for sharing your knowledge!
Thank you very much! It was a big help for me. You save my assignment.God bless.
Sir thanku for such a comprehensive vedio. Beautifully presented sir
According to Wikipedia Ua+Ub should equal Na*Nb. in my data set i have 2 groups for a total of 126 responses. Na=67 Nb=59. Responses range between 0 and 10 in their value.
Group A has:
17 responses of 0 ranked at 11.5
3 responses of 1 ranked at 26
4 responses of 2 ranked at 33
5 respoonses of 3 ranked at 44
6 responses of 4 ranked at 55.5
20 responses of 5 ranked at 78.5
2 responses of 6 ranked at 99
3 responses of 7 ranked at 103
2 responses of 8 ranked at 110
0 responses of 9
and 5 responses of 10 ranked at 120.5
Group B has
5 responses of 0 ranked at 11.5
4 responses of 1 ranked at 26
3 responses of 2 ranked at 33
10 responses of 3 ranked at 44
2 responses of 4 ranked at 55.5
18 responses of 5 ranked at 78.5
1 responses of 6 ranked at 99
2 responses of 7 ranked at 103
7 responses of 8 ranked at 110
0 responses of 9
and 7 responses of 10 ranked at 120.5
So I calculated my Ua and Ub and tried to check whether I did it right, However, when i add Ua and Ub i get 3985, whilst Na*Nb amounts to 3953. So i must be doing something wrong. I have no clue what. Does anyone have any clue what is going wrong?
Happens almost fail-proof. You calculate something wrong, and you know it is but not why... as soon as you start panicking and flailing around until you give up and ask others for help you see your mistake...., Mine was that i calculated the U's wrong. I did Ua= Ra-((Na(Nb+1)/2) instead of Ua=Ra-((Na(Na+1)/2)..... Aaaanyway thanks a bunch for the vid, also helped me alot. Cheers from the Netherlands!
What pen do you use for writing..it is so neat and legible! Needless to say your explanations are on-point!
Excellent...Well explained👏
Thanks so much, you just saved my psychology group´s life!
Very concisely and clearly explained, thank you
Love your videos, please keep making them. I have learned loads =)
I got an A 🥳🥳 thank you!!
Exceedingly well explained
Very clear and strait to the point thanks
The explanation was very clear, thank you for sharing it.
I would like to make a suggestion - include a slightly more elaborate example that connects these numbers to the real world. In this case you mentioned that the numbers came from the results of two distinct treatments. For me it would be more helpful if that was accompanied by something like "The numbers you see correspond to the number of lesions that remained on a person's body after treatment was applied; thus we want to compare the lesion-healing effects of drug A and drug B".
This would make the problem less abstract. Otherwise there is a chance that some people will be able to do the number-crunching, but struggle to come up with an answer when asked "so where can you apply this?".
This was very useful. Thank you!
Thank you. I understand this so much better now
Very nicely explained
Thanks.very easy to understand the way you taught us
Hi, please can you do a video on Wilcoxon signed rank test?
How delightfully easy to understand! :)
But I think the h stastic falls in the acceptance region when represented in a skewness how comes we're rejecting the null hypothesis
Thanks, Eugene!
You, Sir, are too the point !! Kudos!
Why is the U value being calculated differently in this example? The original paper by Mann-Whitney 1947 uses a different formula. You are also not the only professor I have seen using a different formula.
Thank you so much! Made it super easy for me.
Fantastic video. Thank you Eugene
Thankyou random Irish man you saved my geography work horrayyy🎉🎉
So, how many of you are on the day of exam or a day from exam?
I love this man's voice.
One correction whenever your stat value is less than critical value then we accept null hypothesis and reject alternative hypothesis
You are an absolute godsend xx
you’re amazing ! thank you so so much
Two questions -
1. Why did you take U statistic instead of Z for comparing calculated and critical values ?
2. U statistic is calculated with the formulae :
U1 = n1n2 + n1(n1+1)/2 - Sigma R
U2 = n1n2 + n2(n2+1)/2 - Sigma R
your formula for U-statistic is different. I could not find that in any statistic book or internet. All of them give the listed above formula.
would appreciate if you could answer that.
Thanks,
Bhaskar
Cause this just would make sense with a sample size bigger than the one in the video.
You use the z statistic if your sample size is at least bigger than 20, in this case in the video, it is not, so he took the u statistic instead.
same question. our professor used that formula so i got confused.
The formula is different, but the values calculated for U1 and U2 are just exchanged. This is because the above formula just subtracts the formula used in the video from n1n2. In the end while selecting the min(U1,U2) it wouldn’t matter if the values of U1 and U2 are exchanged. But still, I wonder why change the formula anyway.
Also because a z statistic assumes a normal distribution but here the data isn't.
Sound is very good!
Thank you for this sir!
Thank you! You made me actually understand the test. Wow.
Thank you very much. It helped me a lot.
Thanks for this vedio...it's very helpful
Thank you! This is perfect
Mr. Eugene if you are a class teacher and you conduct exams for two different classes but in the subject. mathematics two data is different in number one class is 32 and one class is 14. they are both skewed. con you please use this approach to compare the performances between theses classes?
Great explanation!. What happens when Ua is equal to Ub?.Thanks!
super comprehensive. thanks
why we have rejected the null hypothesis even we know that Ustat< Ucritical
But for a two tailed test , you are supposed to use the higher u calculated value, right??!! so is this a slight error ?
Thank You, Sir
Saved my life
Thanks a lot,well explained❤
I love it so much. Thanks so much
i have been searching and looking for how to do this for five hours now... this finally helped. thank you. may i just ask one question? when you whipped out that paper, and where the columns met and you had to choose either 0.01 or 0.05. why did you choose 0.05?
iirc 0.05 is a significance value of 95%, 0.01 is 99% so if you want to be even more confident use 0.01 but most use 0.05. I could be wrong though as I am trying to remember all this from many years ago.