Mean x vs. function of y in groups of x

DESCRIPTION:

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")

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)
result
"list" (the default), or "matrix"

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.

SEE ALSO:

,

EXAMPLES:

# plot(xy.group(x, y, g=10))    #Plot mean y by deciles of x
# xy.group(x, y, m=100, result="matrix")        #Print table, 100 obs/group