Re: [R] Different random intercepts but same random slope for groups

2015-06-10 Thread li li
Thanks all for the reply, I think what Bert specified is what I wanted. Thanks very much. So this model allows different random intercept term but the same random slope term for the three methods. I have an additional question. I would like to require differnt residual variance also for the three

Re: [R] Different random intercepts but same random slope for groups

2015-06-09 Thread Ben Bolker
li li gmail.com> writes: > [snip] > I'd like to fit a random intercept and random slope model. In my > data, there are three groups. I want to have different random > intercept for each group but the same random slope effect for all > three groups. I used the following R command. > However,

Re: [R] Different random intercepts but same random slope for groups

2015-06-09 Thread Bert Gunter
Thierry: I don't think so. It looks to me like her syntax/understanding is confused. I think the call should be: mod2 <- lmer(result ~ group*time+(group + time|lot), na.action=na.omit, data=alldata) Her request for "the same random slope for each group" -- I assume it's for time -- means to me

Re: [R] Different random intercepts but same random slope for groups

2015-06-09 Thread Thierry Onkelinx
Your model is too complex for the data. This gives you two options: a) simplify the model and b) get more data. Best regards, ir. Thierry Onkelinx Instituut voor natuur- en bosonderzoek / Research Institute for Nature and Forest team Biometrie & Kwaliteitszorg / team Biometrics & Quality Assuranc

[R] Different random intercepts but same random slope for groups

2015-06-09 Thread li li
Hi all, I'd like to fit a random intercept and random slope model. In my data, there are three groups. I want to have different random intercept for each group but the same random slope effect for all three groups. I used the following R command. However, there seems to be some problem. Any sugge