Not really r-specific: Z = (b1 - b2) / SQRT ( SEb1^2 + SEb2^2)
-------Original Message------- From: Gijsbert Stoet <[EMAIL PROTECTED]> Sent: 07/20/03 09:51 PM To: [EMAIL PROTECTED] Subject: [R] how to test whether two slopes are sign. different? > > Hi, suppose I do want to test whether the slopes (e.g. determined with lsfit) of two different population are significantly different, how do I test this (in R). Say for example, I found out what the slope between age and number of books read per year is for two different populations of subjects (e.g. 25 man and 25 woman), say using lsfit. How can I tell whether the slopes are different in R. (And how would I do it for regression coefficients?) Thanks a lot for your help. ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help > ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
