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nlme (version 3.1-166)

Pixel: 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

Arguments

Format

This data frame contains the following columns:

Dog

a factor with levels 1 to 10 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

Examples

Run this code
fm1 <- lme(pixel ~ day + I(day^2), data = Pixel,
           random = list(Dog = ~ day, Side = ~ 1))
summary(fm1)
VarCorr(fm1)

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