# Edist: Expected value of a distribution In popmoments: Population-level moments

## Description

Calculate or approximate the expected value of a distribution. If `support` is missing, it is assumed that the support is continuous and `integrate` is used to approximate the expected value. If the support is countably infinite, then `support` should be chosen to reduce the error associated numerically approximating infinite sums.

## Usage

 `1` ```Edist(dfunc, lower = -Inf, upper = Inf, support, ...) ```

## Arguments

 `dfunc` Function that takes a random variable as its first argument and returns its probability (if `support` in not missing or probability density (if `support` is missing). `lower` Lower limit of the continuous `support` of the distribution (only has an effect if `support` is missing). `upper` Upper limit of the continuous `support` of the distribution (only has an effect if `support` is missing). `support` Values at which to evaluate a distribution with discrete support. `...` Additional arguments to pass to `dfunc`.

## Value

The value of the expected value of `dfunc` (if `support` is not missing) or an approximation to the expected value supplied by `integrate` (if `support` is missing).

## Examples

 ```1 2 3 4 5 6``` ```Edist(dnorm) # exactly 0 Edist(dpois, lambda = 1, support = 0:3) # bad approximation to 1 Edist(dpois, lambda = 1, support = 0:100) # (numerically) exactly 1 Edist(dbinom, size = 4, prob = 0.51, support = 0:4) Edist(dgamma, lower = 0, shape = 2.3, scale = 0.2) Edist(sin, lower = -1, upper = 1) ```

popmoments documentation built on May 31, 2017, 2:51 a.m.