Correlation analysis of non-normal proportion data

Question

Hi JMP community,

I'm analyzing a dataset, and I would like to analyze how the proportion of damage measured on fruits correlate with the proportion of ants and the number of fruit flies. The data is not normally distributed (see histogram), and I'm planning on making a GLM with binomial distribution. I've learned that correlation analysis of proportion data is a bit tricky, and therefore I seek help for how to do this in the best way.

idacj · Answer

Thank you! I've been recommended to try a beta-binomial or zero-inflated beta-binomial model, due to the zero-inflation of my data, but I've never done any of those before, so if it fails I'll try a "normal" binary GLM, which I'm much more familar with.

idacj · Answer

Thank you, I'll try that!

I have about 13.000 data points for each variable, so the sample size is quite large, but the variables are zero-inflated. So model-wise I might try my luck with a zero-inflated beta-binomial distribution, but I've never tried it before, so wish me luck!

Mark_Bailey · Answer

If you know which of the two outcomes occurred in each case, then you could also use logistic regression or a binary generalized linear model. I agree with @statman's suggestions. I am just adding an alternative approach to the analysis.