bodyfat {bayesbr}R Documentation

Percentage of Body Fat

Description

A data frame that contains the proportion of cord fat for individuals calculated through various body measurements of weight, height and circumferences of 252 men who participated in the study by Dr. A. Garth Fisher, Human Performance Research Center, Brigham Young University.

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 (kg/100).

height

Height (m).

neck

Neck circumference (m).

chest

Chest circumference (m).

abdomen

Abdomen circumference (m) ”at the umbilicus and level with the iliac crest”.

forearm

Forearm circumference (m).

hip

Hip circumference (m).

thigh

Thigh circumference (m).

knee

Knee circumference (m).

ankle

Ankle circumference (m).

biceps

Biceps (extended) circumference (m).

wrist

Wrist circumference (m) ”distal to the styloid processes”.

Details

It is possible to find some errors in the table or strange data:

One man (case 42) was measured with over 200 pounds in weight who is less than 3 feet tall, considered that he had a typo when typing 29.5 inches and transformed the data into 69.5 inches;

There was a man with a negative percentage of body fat, it was decided to exclude this data from the table.

Changes to units of measure:

Weight was transformed from lbs to kg / 100 (value 1 corresponds to 100kg);

Height has been transformed from inches to meters;

All columns that were represented in centimeters were transformed into meters.

References

doi: 10.1080/10691898.1996.11910505 Johnson, R. W. (1996). Fitting percentage of body fat to simple body measurements. Journal of Statistics Education, 4(1).

doi: 10.1249/00005768-198504000-00037 Penrose, K. W., Nelson, A. G., & Fisher, A. G. (1985). Generalized body composition prediction equation for men using simple measurement techniques. Medicine & Science in Sports & Exercise, 17(2), 189.

doi: 10.1016/j.csda.2006.05.006 Royston, P., & Sauerbrei, W. (2007). Improving the robustness of fractional polynomial models by preliminary covariate transformation: A pragmatic approach. Computational statistics & data analysis, 51(9), 4240-4253.

Examples

data(bodyfat,package="bayesbr")

bbr = bayesbr(siri ~ age+wrist*neck+chest+
             thigh+wrist| wrist, data = bodyfat,
             iter = 100)

summary(bbr)


bbr = bayesbr(siri ~ I(age/100)+height+chest+
             thigh+wrist| wrist,
             data = bodyfat,iter = 1000)



[Package bayesbr version 0.0.1.0 Index]