R: percentage of body fat determined by underwater weighing
bodyfat
R Documentation
percentage of body fat determined by underwater weighing
Description
A data frame containing the estimates of the percentage of body fat
determined by underwater weighing and various body circumference
measurements for 252 men.
Source: Roger W. Johnson (1996), ”Fitting Percentage of Body Fat to
Simple Body Measurements”, Journal of Statistics Education.
Original data are from K. Penrose, A. Nelson, and A. Fisher (1985),
”Generalized Body Composition Prediction Equation for Men Using
Simple Measurement Techniques” (abstract), Medicine and Science in
Sports and Exercise, 17(2), 189.
Data were supplied by Dr. A. Garth Fisher, Human Performance Research
Center, Brigham Young University, who gave permission to freely distribute
the data and use them for non-commercial purposes.
Note, however, that there seem to be a few errors.
For instance, body densities for cases 48, 76, and 96 seem to have one digit
in error in the two body fat percentage values.
Also note a man (case 42) over 200 pounds in weight who is less than 3 feet tall
(the height should presumably be 69.5 inches, not 29.5 inches).
Percent body fat estimates are truncated to zero when negative (case 182).
Usage
data(bodyfat)
Format
This data frame contains the observations of 252 men:
case
Case number.
brozek
Percent body fat using Brozek's equation: 457/Density - 414.2
siri
Percent body fat using Siri's equation: 495/Density - 450
density
Density determined from underwater weighing (gm/cm**3).
age
Age (years).
weight
Weight (lbs).
height
Height (inches).
neck
Neck circumference (cm).
chest
Chest circumference (cm).
abdomen
Abdomen circumference (cm) ”at the umbilicus and level
with the iliac crest”.
hip
Hip circumference (cm).
thigh
Thigh circumference (cm).
knee
Knee circumference (cm).
ankle
Ankle circumference (cm).
biceps
Biceps (extended) circumference (cm).
forearm
Forearm circumference (cm).
wrist
Wrist circumference (cm) ”distal to the styloid processes”.
R.W. Johnson (1996). Fitting percentage of body fat to simple body measurements.
Journal of Statistics Education [Online], 4(1).
K.W. Penrose, A.G. Nelson, A.G. Fisher (1985). Generalized body composition prediction
equation for men using simple measurement techniques. Medicine and Science
in Sports and Exercise, 17, 189.
P. Royston, W. Sauerbrei (2004). Improving the robustness of fractional polynomial models
by preliminary covariate transformation. Submitted.