Estimation methods

Source data were used to calculate ratios with stature and weight, separately for each dimension's mean (average) and Standard Deviation, building on the technique described and validated by Pheasant (ref 57). The program calculates each output in real time.

The default calculation of each dimension's mean and Standard Deviation was the weighted average of all the known and available sources for each major racial group: each source value was expressed as a ratio to each of the stature and weight means and Standard Deviatons of its own dataset, then an average weighted by sample size was calculated.

The outcomes of these default calculations were inspected, and modified by excluding outliers where appropriate. Internal consistency of the dataset was also sought, some identifiable groups of different dimensions being treated as sets. Very high Standard Deviations were sometimes observed, particularly in datasets from small samples: these were reduced to lie within the ranges of expected Coefficients of Variation (SD/Mean *100) set out in Pheasant (Bodyspace 1986). Data whose measurement points were not clear were not used unless comparison with other data made this information evident.

For most dimensions, the variability observed between different studies of the same population was greater than the variability shown between races, even between Japanese and European data. Caucasian populations were treated as one for proportions to stature, gaining accuracy from the larger collective sample sizes. Differences in proportions between these populations are thus ignored.

see also:

Adult Data

Adjusting for weight

Making fatty dimensions accurate

Adjusting for age