User-Defined Population File Format

Any file extension can work, but the extension .sws (for Safe Work Statistic) is for these types of files.

A population file may contain at most four sections, with the following keywords:

```
MEAN STDEV M
```
```
MEAN STDEV F
```
```
CORR M
```
```
CORR F
```

All sections are optional. The MEAN_STDEV sections must appear before the CORR sections. A given keyword may not appear twice in the same population file.

In the MEAN_STDEV sections, the user may provide values (mean and standard deviation) of every measurement reflecting the population of the study. There must be one line per entry, and each entry must describe, at most, one variable in the following fashion:

<variable> <mean> <stddev>

Where <variable> is the variable reference number, <mean> is the mean value of the variable, and <stddev> is the standard deviation value defining that variable.

A population file may be as simple as the following:

! This is a sample population file
MEAN_STDEV M 
us100 177.0 6.0
MEAN_STDEV F
US100 164.0 6.0
END

In the population file above, the mean value of the stature (variable us100) of a male manikin defines as 177 centimeters (70 inches), with a standard deviation of 6.0. Likewise, the mean stature value of a female manikin is 164 centimeters (64.5 inches).

In the CORR sections, the user may provide correlation values between any pair of variables. The correlation between the two variables is defining as a real number in the range [-1.0, 1.0], expressing the relative dependency between the two variables. The higher the correlation absolute value, the more dependant the variables are on each other.

When defining correlations, there must be one line per entry, and each entry must describe one correlation between one pair of variables, in the following fashion:

Where <variable1> is the reference number of the first variable. <variable2> is the reference number of the second variable, and <correlation> is the correlation value linking the two variables together. The <variable1> must be different from <variable2>, because by definition, the correlation between a variable and itself is always 1.0. The reference number of <variable1> must be lower than the reference number of <variable2>.

If the correlation value given is not within the range [-1.0, 1.0], then an error appears.

The following file gives an example of correlation specifications:

! This is a sample population file
MEAN_STDEV M
us100 177.0 6.0
MEAN_STDEV F                        
us100 164.0 6.0
CORR M
us2 us125 0.772             
us2 us127 0.470                      
us63 us77 0.288           
us63 us81 0.309  
us63 us82 0.288
CORR F 
us2 us125 0.744
us2 us127 0.386
us63 us77 0.231
us63 us81 0.320
us63 us82 0.313
END

All length values appearing in a population file must be in centimeters. Weight values in kilograms and the keywords in a population file are case-sensitive. As such, the keyword mean_stdev f is considered a syntax error.

Provided is an example of a population file, my_population.sws. Also appearing in the samples directory are the five default populations available at manikin creation: American, Canadian, French, Japanese, and Korean.

Refer to Anthropometric Variables for more information. This table contains all information about each variable used in Anthropometry including the reference number, the acronym, the full name, and the definition of each variable.