betabinomialmoments: Compute Moments of Beta-Binomial Probability Mass Functions.

In betafunctions: Functions for Working with Two- And Four-Parameter Beta Probability Distributions and Psychometric Analysis of Classifications

Compute Moments of Beta-Binomial Probability Mass Functions.

Description

Computes Raw, Central, or Standardized moment properties of defined Beta-Binomial probability mass functions.

Usage

betabinomialmoments(
  N,
  l,
  u,
  alpha,
  beta,
  types = c("raw", "central", "standardized"),
  orders = 4
)

Arguments

N	Number of trials.
l	The first (lower) location-parameter of the Beta distribution.
u	The second (upper) location-parameter of the Beta distribution.
alpha	The alpha (first) shape-parameter of the Beta distribution.
beta	The beta (second) shape-parameter of the Beta-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

# Assume 100 observations of a discrete variable with probabilities of
# positive outcomes adhering to a four-parameter Beta distribution with
# location parameters l = 0.25 and u = .95, and shape parameters a = 5 and
# b = 3. To compute the first four raw, central, and standardized moments of
# this distrubution using betabinomialmoments():
betabinomialmoments(N = 100, l = .25, u = .95, alpha = 5, beta = 3,
types = c("raw", "central", "standardized"), orders = 4)

betafunctions documentation built on May 29, 2024, 1:13 a.m.