Hi.Please help if someone can. Problem: I have 2 matrices Eg matrix 1 Freq None Some Heavy 3 2 5 Never 8 13 8 Occas 1 4 4 Regul 9 5 7 matrix 2: Freq None Some Heavy 7 1 3 Never 87 18 84 Occas 12 3 4 Regul 9 1 7 I want to see if matrix 1 is significantly different from matrix 2. I consider using a chi-squared test. Is this appropriate? Could anyone advise? Many thank you. Aaral Singh -- output of sessionInfo(): n/a -- Sent via the guest posting facility at bioconductor.org.