StroupGLMM (version 0.3.0)

Exam7.7: Example 7.7 from Generalized Linear Mixed Models: Modern Concepts, Methods and Applications by Walter W. Stroup (p-235)

Description

Exam7.7 is an explaination of segmented regression

Author

1. Muhammad Yaseen ()

2. Adeela Munawar ()

References

1. Stroup, W. W. (2012). Generalized Linear Mixed Models: Modern Concepts, Methods and Applications. CRC Press.

See Also

DataSet7.7

Examples

library(splines)
library(ggplot2)

DataSet7.7$a  <- factor(x = DataSet7.7$a)
knots <- c(0, 0, 0, 0, 10, 10, 20, 30, 40, 40, 40, 45, 45, 45, 50, 50, 50)

bx <- splineDesign(knots = knots, x = DataSet7.7$x, outer.ok = TRUE)

Exam7.7fm <- lm(formula = y ~ a*bx, data  = DataSet7.7)
anova(Exam7.7fm)

Data  <- data.frame(DataSet7.7, fit = Exam7.7fm$fit)
##---Estimated response surface by using segmented regression
Plot <-
     ggplot(data = Data , mapping = aes(x = x, y = y, colour = a)) +
     geom_point() +
     geom_line(linewidth = 1) +
     ggtitle("Response surface by using segmented regression")

print(Plot)