Gamma Distributions

R uses rate for the $\beta$ parameter of the Gamma distribution. A plot of several Gamma distributions with mean 1 is created by

y<-seq(.01,3,len=50) plot(y, dgamma(y, 10, rate=10), type="l", col = "magenta", ylab="density") lines(y,dgamma(y,0.5,rate=0.5)) lines(y,dgamma(y,1,1), col = "red") lines(y,dgamma(y,2,rate=2), col = "green") lines(y,dgamma(y,3,rate=3), col = "blue") lines(y,dgamma(y,5,rate=5), col = "orange") title("Gamma Distributions With Mean 1")