runs <- 1000
nn <- 100
set.seed(2010)
detections <- replicate(n=runs,expr={covariate <- runif(nn); outcome <- runif(nn)<1/(1+exp(-2*log(2)*covariate+rnorm(nn)))
summary(glm(outcome~covariate,family="binomial"))$coefficients["covariate","Pr(>|z|)"] < .05}) cat("Power:",sum(detections)/runs,"\n")