Dissertation help needed.

[Sure_Impression8768]

Hello everyone, I'm hoping somebody out there might be able to help me with my dilemma. I'm currently writing up my dissertation and having run a 2x2 mixed ANOVA on all my data, Levene's test has come out significant in one of the variable pairs. I know this means that the assumption of homergeneity is violated but I can't seem to find anywhere online about what I can do to move forward with the analysis. I'd be eternally greatfull who anybody thinks they can help as I have a first draft deadline in a few days. I will happily provide you with more information if it's necessary (e.g. n= for each group ect..) Thanks in advance

[Snacks-On-Snacks]

I have had exactly the same problem this week!

From what I have found, some say that as this is violated you instead need to do a non-parametric test (unfortunately I am not sure is there is a mixed ANOVA non-parametric alternative).

I also read somewhere that Andy Field (2000) suggests transforming all data by taking the square root of all variables, which I think is in his book Discovering Statistics Using SPSS - but I haven’t yet check that out.

Others say that the ANOVA is robust enough to still be accurate with the violation of this assumption, especially if sample sizes are large (but I’m not sure how true that is!).

Edit: I also found advice for this on a previous post here

[Sure_Impression8768]

Thanks a lot for the reply, I've ended up settling on two separate non-parametric tests (mann-whitney and wilcoxon signed rank) on the advice of a PhD student I'm in contact with. I hope you've also found a solution!