theta= seq(0,1,.01)

#prior
alpha = 1
beta = 1
#data

#posterior
n=25
t = 18

a = t+ alpha
b = beta - t + n
plot(theta, dbeta(theta,a,b),type="l") #posterior w uniform prior

alpha = 6
beta = 2
quartz()
plot(theta, dbeta(theta, alpha, beta), type = "l")  #prior

#posterior
plot(theta, dbeta(theta, t+alpha, beta-t +n), type="l")
lines(theta, dbeta(theta, alpha, beta), lty=2) #prior
lines(theta, dbeta(theta,a,b),lty=3) #posterior with uniform prior