P-value function of sign test

signP.r

library(ggplot2)
library(dplyr)

sign_p <- function(mu, x, prob=0.5){
  x2 <- x-mu
  x2 <- x2[x2 != 0]
  pos <- sum(x2>0)
  p1 = pbinom(pos, length(x2), prob = prob, lower.tail = FALSE)
  p2 = pbinom(pos, length(x2), prob = prob, lower.tail = TRUE)
  data.frame(p = 2*min(p1, p2), location=mu)
}
curve(pweibull(x+log(2)^(1/1.5),1.5),-log(2)^(1/1.5),4)
abline(h=0.5, lty=2)
abline(v=0, lty=2)

set.seed(123);x <- rweibull(50,1.5) - log(2)^(1/1.5)

dfps <- bind_rows(lapply(sort(x), sign_p, x=x))

ggplot(dfps,aes(x=location))+
  geom_rug()+
  geom_step(aes(y=p))+
  labs(y="p-value")+
  theme_bw(18)