[R] Coloring Stripchart Points, or Better, Lattice Equivalent

[Bryan Hanson]

Below is a revised set of code that demonstrates my question a little more
clearly, I hope.

When plotting all the data (5th panel), col & sym don't seem to be passed
correctly, as the (random) first value for col & sym are used for all points
(run the code, then run it again, you'll see how the 5th panel changes
depending upon col & sym for the first data point).  The 5th panel should
ideally be the "sum" of the 4 panels above, keeping col & sym intact.

Also, I would rather have this in lattice or ggplot2, if anyone sees how to
convert it.

Thanks once again, several of you have made very useful suggestions off
list.  Bryan

samples <- 100 # must be even
index <- round(runif(samples, 1, 100)) # set up data
resp <- rbinom(samples, 1, 0.5)
yr <- rep(c("2005", "2006"), samples/2)
all <- data.frame(index, resp, yr)
all$sym <- ifelse(all$resp == 1, 1, 3)
all$col <- ifelse(all$yr == 2005, "red", "blue")
all$count <- rep(1, length(all$index))
all <- all[order(all$index, all$yr, all$resp),] # for easier inspection
row.names(all) <- c(1:samples) # for easier inspection

one <- all[(all$yr == 2005 & all$resp == 0),] # First 2005/0 at top
two <- all[(all$yr == 2005 & all$resp == 1),] # Then 2005/1
three <- all[(all$yr == 2006 & all$resp == 0),] # Now 2006/0
four <- all[(all$yr == 2006 & all$resp == 1),] # Finally 2006/1

par(mfrow = c(5, 1))
par(plt = c(0.1, 0.9, 0.25, 0.75))
stripchart(one$index, method = "stack", ylim = c(0,10), xlim = c(1,100), col
= one$col, pch = one$sym)
mtext("2005/0", side = 3)
stripchart(two$index, method = "stack", ylim = c(0,10), xlim = c(1,100), col
= two$col, pch = two$sym)
mtext("2005/1", side = 3)
stripchart(three$index, method = "stack", ylim = c(0,10), xlim = c(1,100),
col = three$col, pch = three$sym)
mtext("2006/0", side = 3)
stripchart(four$index, method = "stack", ylim = c(0,10), xlim = c(1,100),
col = four$col, pch = four$sym)
mtext("2006/1", side = 3)
stripchart(all$index, method = "stack", ylim = c(0,10), xlim = c(1,100), col
= all$col, pch = all$sym)
mtext("col & sym always taken from 1st data point when all data is
plotted!", side = 3)