Pixel {MEMSS}

X-ray pixel intensities over time

Description

The Pixel data frame has 102 rows and 4 columns of data on the pixel intensities of CT scans of dogs over time

Format

This data frame contains the following columns:

Dog

a factor with levels A to J designating the dog on which the scan was made

Side

a factor with levels L and R designating the side of the dog being scanned

day

a numeric vector giving the day post injection of the contrast on which the scan was made

pixel

a numeric vector of pixel intensities

Source

Pinheiro, J. C. and Bates, D. M. (2000) Mixed-effects Models in S and S-PLUS, Springer.

Examples

options(show.signif.stars = FALSE)
str(Pixel)
summary(Pixel)
(fm1 <- lmer(pixel ~ day + I(day^2) + (1|Dog:Side) + (day|Dog), Pixel))