EPID 766: Analysis of Longitudinal Data from ... - NCSU Statistics

CHAPTER 2 Epid 766, D. Zhang
I. Random intercept model:
Data from m subjects:
Subject Outcome Time Random
1 y11, y12, ..., y1n1 t11, t12, ..., t1n1 b1
2 y21, y22, ..., y2n2 t21, t22, ..., t2n2 b2
· · ·
i yi1, yi2, ..., yini ti1, ti2, ..., tini bi
· · ·
m ym1, ym2, ..., ymnm tm1, tm2, ..., tmnm bm
Other covariates: xij2, ..., xijp, i = 1, ..., m, j = 1, ..., ni.
A random intercept model assumes:
intercept
yij = β0 + β1tij + β2xij2 + · · · + βpxijp + bi + ǫij.
Graduate Summer Session in Epidemiology Slide 50