Re: [R] Problem with Slope.test function

2011-03-18 Thread Антон Морковин
Good evening! Thanks for your answer, but I don't really understand how to use vcov matrix for comarision of multiple regression line slopes... I've read this theme about using t-test in slope comarision: http://www.mail-archive.com/r-help@r-project.org/msg01713.html but how to use it in case o

Re: [R] Problem with Slope.test function

2011-03-18 Thread Daniel Kaschek
Hi Антон, my approach would be to use the estimated variance of the slope estimator. For your regression models m1 and m2 you can enter vcov(m1) vcov(m2) to get the variance-covariance matrix of m1 and m2. Then, assuming that the slope estimator is normal, you compute the p-value for slope_theo

[R] Problem with Slope.test function

2011-03-18 Thread Антон Морковин
Hi all, I need to test the significnce of difference between slopes of two regression lines and regression line with theoretical line. I try to use Slope.test function from emu package, but an error occured... library(emu) d1<-data.frame(P1=c(1,2,3,5,7,8,9,13,14,15), P2=c(1,2,5,8,11,13,15,15,1