I have two binary variables, naturally dichotomous, yes no They present information on whether a college has multi-stream recycling or single-stream recycling. I did Pearson's product-moment correlation as I read in a research paper that naturally dichotomous variables can be used in pearson's correlation. Ia also did Phi coefficient correlation to see the comparison. I found that the value of association is the same, but the signs have reversed from negative in pearson's to positive in phi. I am not able to understand why the signs changed. Also, additional information, the variables are not exclusive; there are some colleges that have both types of recycling streams. Will that cause a problem in the analysis? Should I re-code these variables?

I have two binary variables, naturally dichotomous, yes no They present information on whether a college has multi-stream recycling or single-stream recycling. I did Pearson's product-moment correlation as I read in a research paper that naturally dichotomous variables can be used in Pearson's correlation. I also did Phi coefficient correlation to see the comparison. I found that the value of association is the same, but the signs have reversed from negative in Pearson's to positive in phi. I am not able to understand why the signs changed. 

Also, additional information, the variables are not exclusive; there are some colleges that have both types of recycling streams. Will that cause a problem in the analysis? Should I re-code these variables?