dutchboys {expectreg}

Data set about the growth of dutch children

Description

Data from the fourth dutch growth study in 1997.

Usage

data(dutchboys)

Format

A data frame with 6848 observations on the following 10 variables.

defnr

identification number

age

age in decimal years

hgt

length/height in cm

wgt

weight in kg

hc

head circumference in cm

hgt.z

z-score length/height

wgt.z

z-score weight

hc.z

z-score head circumference

bmi.z

z-score body mass index

hfw.z

z-score height for weight

z-scores were calculated relative to the Dutch references.

Details

The Fourth Dutch Growth Study is a cross-sectional study that measures growth and development of the Dutch population between ages 0 and 21 years. The study is a follow-up to earlier studies performed in 1955, 1965 and 1980, and its primary goal is to update the 1980 references.

Source

van Buuren S and Fredriks A (2001) Worm plot: A simple diagnostic device for modeling growth reference curves Statistics in Medicine, 20:1259-1277

References

Schnabel S and Eilers P (2009) Optimal expectile smoothing Computatational Statistics and Data Analysis, 53: 4168-4177

Examples

data(dutchboys)

expreg <- expectreg.ls(dutchboys[,3] ~ rb(dutchboys[,2],"pspline"),smooth="f",
                       estimate="restricted",expectiles=c(.05,.5,.95))
plot(expreg)