找出R中n个泊松值的期望值

Question

我写了以下代码：

n <- 5
lambda <- 2
randomNumbers <- rpois(n, lambda)
prob <- dpois(randomNumbers, lambda)

到目前为止我的代码是否正确？

如何找到5个泊松值的预期值？

eX <- mean(randomNumbers)

要么，

weighted.mean(randomNumbers, prob)

Answer 1

n <- 5
lambda <- 2
randomNumbers <- rpois(n, lambda)
# estimate of P(X = 0), for example
mean(randomNumbers == 0)
# estimate of E[X]
mean(randomNumbers)