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# Column statistic

- OCCURRENCE
- DESCRIPTION
- NOTES
- NOTES
- WARNINGS
- BUGS

## OCCURRENCE

### ARB_NT/SAI/Create SAI from Sequences/Positional Variability ...

## DESCRIPTION

### Calculates the base and frequencies positional variability for each column independently. It uses the parsimony method to find the minimum number of mutations for each site.

### The result can be used by:

- Parsimony to weight the characters properly
- Neighbour joining to estimate the distances more accurately.
- Filter

### Result:

    '.'                          Less than 10% valid characters

    '0123456789ABCDE...'         The higher the number the more conserved the site is.
                                 Stepping 2 position rightwards in the list of given char,
                                 means half number of mutations (eg .'7' means "half number
                                 of mutations compared to '5'")

## NOTES

### Use the biggest tree you have.

## NOTES

### @@@ Compare it to consensus and max frequency.

## WARNINGS

### if you have only small trees (<100 species), forget this function.

## BUGS

### No bugs known