lmtest (version 0.9-34)

Mandible: Mandible Data

Description

Mandible Data.

Usage

data(Mandible)

Format

Data from 167 fetuses, especially:

age

gestational age in weeks.

length

mandible length in mm.

Source

The data was originally published by Chitty et al., 1993, and analyzed in Royston and Altman, 1994 (the data is given there). Only measurements with age <= 28<="" code=""> were used in this analysis.

References

L. S. Chitty and S. Campbell and D. G. Altman (1993), Measurement of the fetal mandible -- feasibility and construction of a centile chart., Prenatal Diagnosis, 13, 749--756.

P. Royston and D. G. Altman (1994), Regression Using Fractional Polynomials of Continuous Covariates: Parsimonious Parametric Modelling. Applied Statistics, 43, 429--453.

Examples

data(Mandible)
lm(length ~ age, data=Mandible, subset=(age <= 28))