# ms2pfmg: Convert moult scores to proportion of feather mass grown In moult: Models for Analysing Moult in Birds

## Description

Convert moult scores obtained for single feathers into overall proportion of feather mass grown.

## Usage

 `1` ```ms2pfmg(ms, fm) ```

## Arguments

 `ms` vector of moult scores. Ideally, each moult score is a character string of one individual's individual feather moult scores, each between 0 and 5, e.g. "555444000" if only nine primaries are of interest. `fm` vector of relative feather mass, corresponding to each feather in ms.

## Details

`ms` will usually be a vector of 9 or 10 primary feather scores, but single feathers can be given, in which case `fm` is ignored. The method used here assumes that a moult score of 1 for any feather corresponds to 1/8th of the feather grown, 2 corresponds to 3/8th = 0.375, etc.. The proportion of feather mass grown is then a weighted sum over all feathers, with weights equal to the relative weight (compared to the total weight) of each feather (Underhill and Zucchini 1988).

## Value

`ms2pfmg` returns a single value between 0 and 1: proportion of total feather mass grown.

Bo T. Bonnevie

## References

Underhill, L. G. and Zucchini, W. (1988) A model for avian primary moult. Ibis 130, 358–372.

`predict.moult`, `moult`
 ```1 2 3 4 5 6 7 8``` ```## relative primary feather mass of the 10 primary feathers ## (as proportion of total feather mass) for Sanderlings fm.sand <- c(0.0385, 0.0458, 0.0544, 0.0680, 0.0827, 0.1019, 0.1199, 0.1417, 0.1604, 0.1867) ms2pfmg(3, 0.2) # single feather ms2pfmg(3, 1) ms2pfmg("5555500000", fm.sand) ```