Eugenio - > I am confused with SMATR's test for common slope. My null hypothesis here is > that all slopes are parallel (common slopes?), right? > So if I get a p value < 0.05 means that we can have confidence to reject it? > That slopes are different? > Or the other way around? it means that we have statistical confidence that > the slopes are parallel?
Try this: set.seed(5) n <- 20 x <- rnorm(n) y1 <- 2 * x + rnorm(n) y2 <- 2 * x + rnorm(n) y3 <- 4 * x + rnorm(n) # Slopes approximately equal slope.com(x = c(x, x), y = c(y1, y2), groups = rep(c(1,2), each = n)) #$p #[1] 0.4498037 # Slopes of 2 and 4 slope.com(x = c(x, x), y = c(y1, y3), groups = rep(c(1,2), each = n)) #$p #[1] 0.0003850332 Cheers, Kevin ------------------------------------------------- Kevin M. Middleton Department of Biology California State University San Bernardino ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
