# betamoments

##### Compute Moments of Two-to-Four Parameter Beta Probability Density Distributions.

Computes Raw, Central, or Standardized moment properties of defined Standard Beta probability density distributions.

##### Usage

```
betamoments(
alpha,
beta,
l = 0,
u = 1,
types = c("raw", "central", "standardized"),
orders = 4
)
```

##### Arguments

- alpha
The Alpha shape parameter of the PDD.

- beta
The Beta shape parameter of the PDD.

- l
The first (lower) location parameter of a four-parameter distribution.

- u
The second (upper) location parameter of a four-parameter distribution.

- types
A character vector determining which moment-types are to be calculated. Permissible values are "raw", "central", and "standardized".

- orders
The number of moment-orders to be calculated for each of the moment-types.

##### Value

A list of moment types, each a list of moment orders.

##### References

Hanson, B. A (1991). Method of Moments Estimates for the Four-Parameter Beta Compound Binomial Model and the Calculation of Classification Consistency Indexes. American College Testing Research Report Series.

##### Examples

```
# NOT RUN {
# Assume some variable follows a four-parameter beta distribution with
# location parameters l = 0.25 and u = .75, and shape
# parameters a = 5 and b = 3. To compute the first four
# raw, central, and standardized moments of this distrubution using
# betamoments():
betamoments(a = 5, b = 3, l = .25, u = .75,
types = c("raw", "central", "standardized"), orders = 4)
# }
```

*Documentation reproduced from package betafunctions, version 1.4.0, License: CC0*