Hi all,
I'm attempting to compare differences between 2 unequal group sizes (one ~ 97 the other ~ 714). The reason for the large discrepancy is I am looking at a program done by one class to see if it is significantly different than what has occurred in previous classes. I've been reading about robust stats recently and decided to use a yuen bootstrap in RStudio from the WRS2 package for a more valid comparison, especially with the difference in sample size.
My formula is yuenbt(DataExample$PT500 ~ DataExample3$ClassPT500, tr = 0.2, nboot = 599, side = TRUE)
and it returns
Call:
yuenbt(formula = DataExample$PT500 ~ DataExample$ClassPT500,
tr = 0.2, nboot = 599, side = TRUE)
Test statistic: NA (df = NA), pvalue = 0
Trimmed mean difference: 65
95 percent confidence interval:
NA NA
The NA's return on other variables that I've tried out as well, or in some cases the confidence interval will state INF. Any ideas why this is happening (such a big difference in sample size?) and suggestions on what the next best step would be are greatly appreciated. I've updated a spreadsheet with some of the variables.
Thank you in advance.
I'm attempting to compare differences between 2 unequal group sizes (one ~ 97 the other ~ 714). The reason for the large discrepancy is I am looking at a program done by one class to see if it is significantly different than what has occurred in previous classes. I've been reading about robust stats recently and decided to use a yuen bootstrap in RStudio from the WRS2 package for a more valid comparison, especially with the difference in sample size.
My formula is yuenbt(DataExample$PT500 ~ DataExample3$ClassPT500, tr = 0.2, nboot = 599, side = TRUE)
and it returns
Call:
yuenbt(formula = DataExample$PT500 ~ DataExample$ClassPT500,
tr = 0.2, nboot = 599, side = TRUE)
Test statistic: NA (df = NA), pvalue = 0
Trimmed mean difference: 65
95 percent confidence interval:
NA NA
The NA's return on other variables that I've tried out as well, or in some cases the confidence interval will state INF. Any ideas why this is happening (such a big difference in sample size?) and suggestions on what the next best step would be are greatly appreciated. I've updated a spreadsheet with some of the variables.
Thank you in advance.
Attachments

346.7 KB Views: 3