Orthodont.unstacked: Orthodont.unstacked: Measurements from a Dental Study on...

In thoree/stat340: Data and functions for BIAS at NMBU

Orthodont.unstacked: Measurements from a Dental Study on Children

Description

The data in this data set is from measurements of 27 children at the ages 8, 10, 12 and 14 (11 girls and 16 boys) and was collected by investigators at the University of North Carolina Dental School. By the use of x-ray, they measured the children's distance between the centre of the pituitary and the pterygomaxillary fissure.

Usage

Orthodont.unstacked

Format

A data frame with 27 observations (rows) and 5 variables (columns).

	Column name	Data type	Description	Values
[,1]	gender	factor	The child's gender	(F, M)
[,2]	age8	numeric	The distance in mm measured at age 8	(16.5 - 27.5)
[,3]	age10	numeric	The distance in mm measured at age 10	(19 - 28)
[,4]	age12	numeric	The distance in mm measured at age 12	(19 - 31)
[,5]	age14	numeric	The distance in mm measured at age 14	(19.5 - 31.5)

References

Potthoff, R. F. and Roy, S. N. (1964) A Generalized Multivariate Analysis of Variance Model Useful Especially for Growth Curve Problems. Biometrika, 51, 313–326.

Examples

# Combine the age columns
stacked_orthodont <- cbind(Orthodont.unstacked[1],
                           stack(Orthodont.unstacked[2:5]))

# Rename columns
colnames(stacked_orthodont)[2:3] <- c("Distance", "Age")

# Measured distance based on gender and age
boxplot(Distance ~ gender*Age, data = stacked_orthodont)

thoree/stat340 documentation built on June 30, 2024, 4:04 p.m.