How to interpret coefficients of standardized variables in a Poisson regression?

Question

I am studying the determinants of patenting; accordingly my response variable in a Poisson/count data model is the number of patents in a year and country (i.e. this is a macro-panel study; I use dummies for fixed effects).

I would like to be able to compare two variables measured in different units, i.e. R&D spending in $ and the number of universities. If this were an OLS, I would simply standardize both variables (create "z-scores") and compare the effect of 1 standard deviation increase in the variables. Does it work the same way in a Poisson, i.e. are the coefficients of standardized variables in a Poisson regression output equally comparable, even though they do not have the same straightforward interpretation?

Thanks for any answer or pointer in the right direction!

Answer 1

When people do ths for linear regression they often also standardise the outcome variable as well which you would not do in a Poisson regression. With that caveat the interpretation would be similar.

I do wonder though with the variables you quote why you would want to do this. At present you can say something like: having one extra university is associated with a 5% increase whereas spending 10000 dollars is associated with a 6% increase. That seems more meaningful to me than saying that changing the number of universities by 0.1 standard deviation is the same as changing the spend by 0.15 standard deviations.