RaviSelker

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• Interaction contrasts can be pretty complex, and we're not quite sure how to implement this in a way that is still very easy to use. So we would like to include this at some point but don't expect it any time soon.

  in Interaction contrasts Comment by RaviSelker September 2016
• Hi Matt, I checked the code that is used to create the contrast weights and there seems to be an error in the way they are created at the moment. I fixed it now, and committed the change (see, https://github.com/jasp-stats/jasp-desktop/pull/1385/co…

  in Inconsistent contrasts Comment by RaviSelker July 2016
• This is how we calculate skewness and kurtosis: .descriptivesKurtosis <- function(x) { # Kurtosis function as in SPSS: # http://www.ats.ucla.edu/stat/mult_pkg/faq/general/kurtosis.htm # http://en.wikipedia.org/wiki/Kurtosis#Estimators_…

  in Skewness and kurtosis values in descriptives Comment by RaviSelker May 2016
• Are you doing the analysis on the "ThreeWayRepeatANOVA.csv" data set? Because that is the one that you should use in JASP as this is in wide format. The "Ancova.csv" is in long format. If I try the analysis I assume you want to d…

  in JASP: DFs for ANCOVA with within-subjects design Comment by RaviSelker May 2016
• Ah, I thought you were talking about the regular ANOVA. I'm not completely sure how SPSS produces its results so I will look into it and get back to you.

  in Polynomial contrasts Comment by RaviSelker April 2016
• I see that SPSS provides t-tests and an omnibus F test which is the same as the result in the ANOVA table. As the F test is already provided in the regular ANOVA table in JASP I don't really see a reason to give the same exact result again for the c…

  in Polynomial contrasts Comment by RaviSelker April 2016
• Sorry for not getting back to you sooner. I discussed it with the maintainer of the R package and it appears that the R function assumes that the variances (and thus the SE's) are equal to each other. This makes sense because one of the assumptions …

  in [open] JASP: Standard Error in Post-hoc comparisons Repeated Measures ANOVA Comment by RaviSelker April 2016
• Hi Marie, Thanks for you response. It's definitely not possible for eta squared to be bigger than partial eta squared as SStotal will always at least include SSerror and SS. In your hand calculations you forgot to include the SSerror in SStotal, an…

  in Repeated Measures ANOVA Effect Size Comment by RaviSelker April 2016
• Can you please provide an example. The only reason for them to have the same value would be if you only have one factor (as SStotal = SS + SSerror). I'm also pretty sure that the formula we use to calculate omega squared is the correct one (https://…

  in Repeated Measures ANOVA Effect Size Comment by RaviSelker April 2016
• Yes, this is a bug. We already fixed it (https://github.com/jasp-stats/jasp-desktop/pull/1248) and we are going to do a small release soon to incorporate this fix.

  in No t values for linear regression in JASP 0.7.5.5 Comment by RaviSelker March 2016
• We use the lsmeans package in R (in combination with the afex package) to calculate post-hoc tests for repeated measure. Here's an example of how we use it: # load packagesrequire(afex)require(lsmeans)# simulate data setset.seed(1)dataset <- dat…

  in [open] JASP: Standard Error in Post-hoc comparisons Repeated Measures ANOVA Comment by RaviSelker March 2016
• Hi Tom, JASP only allows repeated measures data in wide format. Your data is in long format (for the difference, see http://www.theanalysisfactor.com/wide-and-long-data/), so you must reformat the data in order to use it in JASP. Subsequently, to r…

  in JASP: DFs for ANCOVA with within-subjects design Comment by RaviSelker February 2016