"pair"## S3 method for class 'pair':
plot(x, sortdif = FALSE, ra = "auto",
main = NULL, col.lines = (1:dim(x$threshold)[2]),
type = "b", xlab = "items", ylab = "logits",
pch = (1:dim(x$threshold)[2]), las = 3, cex.axis = 0.8,
...)"pair""auto" (default) or
an numeric, defining the (logit) range for y-axisplotplotplotplotplotplotplot