Compute mean x vs. a function of y (e.g. median) by quantile
groups of x or by x grouped to have a given average number of
observations. Deletes NAs in x and y before doing computations.

Usage

xy.group(x, y, m=150, g, fun=mean, result="list")

Value

if result="list", a list with components x and y suitable for plotting.
if result="matrix", matrix with rows corresponding to x-groups and columns named
n, x, and y.

Arguments

x

a vector, may contain NAs

y

a vector of same length as x, may contain NAs

m

number of observations per group

g

number of quantile groups

fun

function of y such as median or mean (the default)