# DESC_STA 1.0

## DESCRIPTION

DESC_STA is a program which makes basic descriptive statistics for samples from the normal distribution. It calculates the mean, variance, standart deviation and standart error of the mean.

## INPUT DATA FORMAT

The input data _have to be_ in a following format:

- the first line must specify data name (it's for your convinience) and number of traits under investigation. Data name must be no longer then one word (it means that you have to use not spaces, for example, data name "my_data_on_height" is appropriate and data name "my data on height" is not). The number of traits is following the data name and it must be separated from data name by at least one space. Example of the first line:
my_data_on_height 3

- The next lines contains your data data. You have to begin measurements on each trait with it's name, then you have to type your data and then you have to finish it with some non-numerical symbol (any letter will be appropriate). For example
in_human 1.50 1.83 2.01 1.783 2 1.6 fins

So you must have a file like this:

my_data_on_height 3
in_human 1.50 1.83 2.01 1.783 2 1.6 f
in_trees 124 124 275 125 134 178 198 190
156 21 36 389 387 905 498 f
in_my_family 1.67 1.78 1.24 f

One more example is provided in file named "input.dat"

## USAGE

The usage sintaxis is, for example:

C:\>desc_sta.exe

The parameters in brackets are optional ones. Here "input.dat" is a file containing your data, "output.dat" is an output file, which is made by the program. It contains mean, variance, standart deviation and standart error of the mean of a set of your data. If you have not specified a input and output data files' names the program will search for "input.inp", which is default name for input data file and will write information into file named "output.out".

## THEORETICAL BACKGROUND

#### TERMS:

- SUM -- summation over i
- Xi -- particular i-th observation
- N -- number of measurements
- X^2 -- the second power of X
- SQRT(X) -- the square root of X

#### FORMULAS:

- Mean: M=(1/N)*SUM Xi
- Variance: VAR=(N/N-1)*[(1/N)*SUM(Xi^2)-M^2]
- Standart deviation: SD=SQRT(VAR)
- Standart error of the mean: SE=SD/SQRT(N)

### WARRANTY

This software is distributed free _without any_ warranty.

### AUTHOR

Please report any bugs and send your comments and suggestions to

yurii@bionet.nsc.ru

http://mga.bionet.nsc.ru/soft/