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ECOM II

6.1

Summary of data

This screen gives summary statistics for both the raw and the working data sets.

When initially activated the screen shows general statistics for the working

environmental data set. This can be changed using the options in the panel below the

grid.

When first activated the data grid will display the following general statistics for the

working data.

No. of variables (rows)   This is the number of rows of data in the data set.

No. of samples (cols)   This is the number of columns in the data set.

No. of zero cells   This is the number of zero entries in the data matrix.

No. of non zero cells   This is the number of non zero entries in the data matrix.

% of zero cells   This is the number of zero entries divided by the number of cells

in the data matrix.

Maximum value   This is the maximum value in the data matrix.

Minimum value   This is the minimum value in the data matrix.

Range   This is the difference between the maximum and minimum values.

Mean   This is the mean of all the values in the data matrix.

Standard deviation   This is the standard deviation of all the values in the data

matrix.

   Median   This is the median of all the values in the data matrix.

By using the radio buttons you can get a wider range of statistical facts about both

the environmental and biological variables and the sites. Remember that these

calculations can be undertaken on either the working or raw data.

To print the output select File|Print

For more information on the statistics presented see:

General dataset statistics

Statistics for columns and rows

Copyright 2004  PISCES Conservation Ltd