| plot.predict.ideal {pscl} | R Documentation |
Plot classification success rates by legislators, or by roll calls, using predictions from ideal.
plot.predict.ideal(x, type = c("legis", "votes"),...)
x |
an object of class predict.ideal. |
type |
string; one of legis or votes. |
... |
further arguments passed to or from other methods. |
type="legis" produces a plot of the “percent correctly
predicted” for each legislator/subject
(using the classification threshold set in
predict.ideal) against the estimated ideal point of each
legislator/subject (the estimated mean of the posterior density of the
ideal point), dimension at
a time. If the legislators' party affiliations are availble in the
rollcall object that was passed to ideal,
then legislators from the same party are plotted with a unique color.
type="votes" produces a plot of classification rates for each
roll call, by the percentage of legislators voting for the losing
side. The x-ordinate is jittered for clarity.
After drawing plots on the current device, exits silently returning invisible(NULL).
Simon Jackman jackman@stanford.edu
data(s109)
id1 <- ideal(s109,
d=1,
normalize=TRUE, ## local identification in 1d
store.item=TRUE, ## need this for predictions
maxiter=500, ## short run for demo purposes
burnin=100,
thin=10)
phat <- predict(id1)
plot(phat,type="legis")
plot(phat,type="votes")