mackp {gamair}R Documentation

Prediction grid data for 1992 mackerel egg model

Description

This data frame provides a regular grid of values of some predictor variables useful for modelling mackerel egg abundances. Its main purpose is to enable mackerel egg densities to be predicted over a regular spatial grid within the area covered by the 1992 mackerel egg survey (see mack), using a fitted generalised additive model.

Usage

data(mackp)

Format

A data frame with 5 columns. Each row corresponds to one spatial location within the survey area. The columns are as follows:

Details

The grid is defined on a series of 1/4 degree lon-lat squares.

References

Borchers, D.L., S.T. Buckland, I.G. Priede and S. Ahmadi (1997) "Improving the precision of the daily egg production method using generalized additive models". Can. J. Fish. Aquat. Sci. 54:2727-2742.

Examples

## example of how to use `area.index' to paste gridded info.
## into a square grid (of NA's) for plotting
data(mackp)
lon<-seq(-15,-1,1/4);lat<-seq(44,58,1/4)
zz<-array(NA,57*57)
zz[mackp$area.index]<-mackp$b.depth
image(lon,lat,matrix(zz,57,57))

[Package gamair version 0.0-5 Index]