I have a data-set containing rain value for 6 stations and station coordinates (lat,lon). I used lm function taking lat,lon,day, their interaction and rain as below:
G <- auto_basis(data = Rain[,c("lon","lat")] %>% *# Take dataset* SpatialPoints(), # To sp obj nres = 1, # One resolution type = "Gaussian") S <- eval_basis(basis = G, # basis functions s = Rain[,c("lon","lat")] %>% # spat locations as.matrix()) %>% # conv. to matrix as.matrix() # results as matrix colnames(S) <- paste0("B", 1:ncol(S)) # assign column names Rain2<- cbind(Rain, S) %>% # append S to dataset select( -mydate) # will not be using in the model Rain_lm <- lm(z ~ (lon + lat + day)^2 + ., # model data = select(Rain2,-id)) # omit station id Rain_lm %>% summary()
The LM summary shows NA for Estimate regression coefficients and the standard errors Std. Error and of lat:lon interaction . Could you please help me to interpret the producing NAs?