Output for Wilcoxon signed-rank test correct?

lindeloev / tests-as-linear

Common statistical tests are linear models (or: how to teach stats)

https://lindeloev.github.io/tests-as-linear/

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Output for Wilcoxon signed-rank test correct? #17

Closed SteveRxD closed 5 years ago

SteveRxD commented 5 years ago

Hi, thanks for this great resource! I'm working through the book now.

Can I confirm that the p-values published in the table of section '4.1.3 R code: Wilcoxon signed-rank test' are correct? I get different p-values for both the Wilcoxon test and the linear model using signed ranks (0.2628 and 02650 respectively). I have been able to replicate all other tests in the book so far using the toy data set. Thanks.

lindeloev commented 5 years ago

They are not completely identical, as are none of the non-parametric "equivalents". In your case, p is off by 0.0022. This, you can also see in the website version.

Or are you pointing to a different issue?

SteveRxD commented 5 years ago

My apologies, I see the problem - it was to do with the toy data. When reproducing your work I created the toy data sets in a different order (x, y, y2 instead of y, x, y2). When I ran it again I get the same results as you.