Hi I analyze grid based, spatial data, and for each grid cell I have several variables (fire severity, elevation, vegetation etc.). I would like to know if there is e.g. lower fire severity above 3000 m a.s.l. as compared to below 3000 m. Since the data are highly correlated, I wondered if it's possible to test the independence of two variables using chi-square tests. Is there any R function that could be used to correct the p values of a chi-square test? Thanks for any advice, Christof