.Random.seed <- c(1, 45, 62, 31,  5,  3, 57, 25, 42, 48, 62,  0)
setps(cal.graph)
n <- 400; k <- n/2
x1 <- runif(n); x2 <- runif(n); x3 <- runif(n); x4 <- runif(n);
x5 <- runif(n); x6 <- runif(n); x7 <- runif(n)
logit <- 2*(x1-.5) + 1.5*(x3-.5) - 2*(x5-.5) + 1*(x6-.5) + 1*(x7-.5)
P <- 1/(1+exp(-logit))
y <- ifelse(runif(n)<=P, 1, 0)
cat(sum(y[1:k]),sum(y[(k+1):n]),"\n")
d <- data.frame(x1,x2,x3,x4,x5,x6,x7,y)
attach(d,1)
f <- lrm(y ~ x1+x2+x3+x4+x5+x6+x7, subset=1:k)
f
pred.logit <- predict(f, d[(k+1):n,])
phat <- 1/(1+exp(-pred.logit))
val.prob(phat, y[(k+1):n], m=50, legendloc=F, statloc=F, 
   riskdist="predicted", logistic.cal=F)