Hi, when I run > plot.default(z1, z2, xlab = "x", ylab = "y", main = "xxxx", pch = "+") > abline(lm(z1 ~ z2)) then the plot is plotted perfectly (scatterplot), however, the lm() function doesnt appear on the plot. What could be wrong? (Yesterday it worked perfectly, with the lm() line.) Running R 2 on OS X. Mathias Hunskår Furevik Norway