Re: [R] predict function in regression analysis

2015-05-06 Thread Stéphane Adamowicz
Maybe this is what you wanted : Data - structure(list(y = c(4.5, 4.5, 4.7, 6.7, 6, 4.4, 4.1, 5.3, 4, 4.2, 4.1, 6.4, 5.5, 3.5, 4.6, 4.1, 4.6, 5, 6.2, 5.9, 3.9, 5.3, 6.9, 5.7), lot = c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L), duration =

[R] predict function in regression analysis

2015-05-05 Thread li li
Hi all, I have the following data in which there is one factor lot with six levels and one continuous convariate time. I want to fit an Ancova model with common slope and different intercept. So the six lots will have seperate paralell regression lines.I wanted to find the upper 95% confidence

Re: [R] predict function in regression analysis

2015-05-05 Thread Bert Gunter
I think you want CI's for intercepts, not means (what is a mean for a line??). If so, the ?confint function will give this to you for the lot effect estimates when applied to a model fitted without an intercept: myfit -lm(y~ lot-1+time) confint(myfit) Further discussion should be directed to a