I am working on a dataset where two raters indicated whether or not particular features were present in the same individuals. So each individual was assessed by each of these two raters and received a score of 0 for no feature and 1 for a feature. Most of the features were very minor and as a result, many of the individuals received a 0 from both raters on that feature.
I am trying to calculate a Cohen's Kappa in R for each feature to determine reliability between the two raters, but my the kappa values are very low and I am thinking it has to do with the prevalence of the 0 values for the ratings. I saw there used to be a package in R that did something called the Bryt's Kappa for prevalence correction, but this no longer exists.
Is anyone aware of Kappa calculations in R or SPSS that can be done that account for this prevalence?