I prepared a reproducible example with an example of dataset here: patient <- c(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2) month <- rep (1:10, 2) fev1 <- c(58, NA, NA, NA, 57, NA, NA, NA, NA, 60, NA, NA, NA, NA, 32,… Read More R how to obtain the mean of previous values depending on a second column with data in long format

I have data like This (repeated measures), Testscore is the dependent variable, Time is the measurement time. | ID | TIME | TESTSCORE | VAR1 | VAR2 | |:– |:—-:|:———:|:—-:|:—-:| |20 |1 | 100 | 50 | 0 | |20 |2 |200 | 60 | 1 | |30 |3 | 400 | 70 | 0… Read More mixed model specification

Consider the sleepstudy data in the lme4 package as shown below. The contains 18 subjects with repeated measurements of Reaction (Reaction is the response) taken on different days. library("lme4") head(sleepstudy) Reaction Days Subject 1 249.5600 0 308 2 258.7047 1 308 3 250.8006 2 308 4 321.4398 3 308 5 356.8519 4 308 6 414.6901… Read More Prediction in a linear mixed model in R