[R] Performing negative binomial regression on data, using stepwise selection

hello all, I've been trying for some time to try and model a big dataset using generalized linear models, or more precisely negative binomial regression. Unfortunately i have too many explanatory variables and i'd like to cut some of them off using a stepwise selection method. i've been struggeling

[R] multiplying columns in matrix

Say I have two matrixes: one is 8x28 and other 8x8 I'd like to multiply, for example, first and second column from the 8x8 and plant them in first column of 8x28. Then take first and third of 8x8 and plant into second column of 8x28.etc. Any ideas? Thanks! [[alternative HTML ver