# Recent content by Vthompson

1. ### Comparing means

Thank you very much for your help!!
2. ### Comparing means

Hello, I hope you can help. I am working with numerical data and I wish to compare means. Data set 1 has N=30 (normally distributed) Data set 2 has N=24 (not normal) Data set 3 has N=24 (not normal) Data set 4 has N=12 (not normal) I used the Shapiro Wilks test to test for normality and any p...
3. ### Applying the Bonferroni Correction to a T-Test considered

Yes it is related to the multiple testing ( data set A-normal will be compared to data set E-non normal). I will use the Mann-Whitney for that one.
4. ### Applying the Bonferroni Correction to a T-Test considered

Thanks O for all your input. Yes, I tested all the data sets separately using the Shapiro-Wilks test which found the data set not normal for E. The p value was .004.

6. ### Applying the Bonferroni Correction to a T-Test considered

Hello O, Thanks for your reply! 1) Shouldn't I divide by 4 because I am comparing AB, AC, AD and AE? Or are you saying because I am using a T-Test for AB, AC & AD, I should divide by 3? But in this case, when using the Mann Whitney test for comparing AE, do I leave alpha at .05? 2) The sample...
7. ### Applying the Bonferroni Correction to a T-Test considered

Hello! I need your help please:) I am comparing the mean scores for an exam for one class (A) to four different classes (B,C,D,E), such as AB, AC, AD and AE. The data for all classes is normal but in class E. I am performing a T-Test for AB, AC and AD only, but using the Mann Whitney test for...
8. ### Comparing withdrawal rates for a course

Thanks every one. You’ve been such a great help!
9. ### Comparing withdrawal rates for a course

Excellent. Thank you for confirming what I thought it was.
10. ### Comparing withdrawal rates for a course

Hello!! Which statical test should I use to compare withdrawal rates for a course for two semesters. I know I can report the means but need to know if the difference is significant. For example: Fall2017 10 out of 33 students withdrew Spring2018 5 out of 66 students withdrew Thank you in...