# betaParametrizationConverters: Functions to convert between shape parameters a and b for... In MBASED: Package containing functions for ASE analysis using Meta-analysis Based Allele-Specific Expression Detection

## Description

Functions to convert between shape parameters a and b for beta distribution and parameters mu (mean) and rho (dispersion).

## Usage

 ```1 2 3``` ```getMuRho(a, b, checkArgs = FALSE) getAB(mu, rho, checkArgs = FALSE) ```

## Arguments

 `a,b` shape parameters for beta distribution. Must be >0. `checkArgs` single boolean specifying whether arguments should be checked for adherence to specifications. DEFAULT: FALSE `mu,rho` mean and dispersion parameters for beta distribution, respectively. Must be in (0,1) interval, although rho is allowed to take on value of 0 (binomial distribution).

## Details

getMuRho takes in shape parameters a and b and returns list with parameters mu (a/(a+b)) and rho (1/(a+b+1)). The function is vectorized (both a and b can be vectors (of the same length) or matrices (of the same dimension)).

getAB takes in shape mean and dispersion parameters mu and rho and returns shape parameters a (mu*(1/rho-1)) and b ((1-mu)*(1/rho-1)). The function is vectorized (both mu and rho can be vectors (of the same length) or matrices (of the same dimension)).

## Value

getMuRho returns a list with 2 elements: mu and rho (vectors, if the arguments a and b are vectors).

getAB returns a list with 2 elements: a and b (vectors, if arguments mu and rho are vectors). For values of rho=0, the resulting entries are NA.

Other bbFunctions: `vectorizedRbetabinomAB`, `vectorizedRbetabinomMR`, `vectorizedRbetabinomMR`
Other bbFunctions: `vectorizedRbetabinomAB`, `vectorizedRbetabinomMR`, `vectorizedRbetabinomMR`
 ```1 2 3 4``` ```MBASED:::getMuRho(a=1, b=1) MBASED:::getAB(mu=1/2, rho=1/3) MBASED:::getMuRho(MBASED:::getAB(mu=0.7, rho=0.0045)\$a, MBASED:::getAB(mu=0.7, rho=0.0045)\$b) MBASED:::getAB(MBASED:::getMuRho(a=0.2, b=4)\$mu, MBASED:::getMuRho(a=0.2, b=4)\$rho) ```