R: Credible Interval Computation for the ash object

ashci {ashr} | R Documentation

## Credible Interval Computation for the ash object

### Description

Given the ash object returned by the main function ash, this function computes a posterior credible interval (CI) for each observation. The ash object must include a data component to use this function (which it does by default).

### Usage

    ashci(
      a,
      level = 0.95,
      betaindex,
      lfsr_threshold = 1,
      tol = 0.001,
      trace = FALSE
    )

### Arguments

`a` | the fitted ash object
`level` | the level for the credible interval, (default=0.95)
`betaindex` | a vector consisting of locations of betahat where you would like to compute the credible interval
`lfsr_threshold` | a scalar, if specified then computes CIs only for observations more significant than that threshold.
`tol` | passed to uniroot; indicates desired accuracy.
`trace` | a logical variable denoting whether some of the intermediate results of iterations should be displayed to the user. Default is FALSE.

### Details

Uses uniroot to find credible interval, one at a time for each observation. The computation cost is linear in number of observations.

### Value

A matrix, with 2 columns, ith row giving CI for ith observation

### Examples

    beta = c(rep(0,20),rnorm(20))
    sebetahat = abs(rnorm(40,0,1))
    betahat = rnorm(40,beta,sebetahat)
    beta.ash = ash(betahat, sebetahat)

    CImatrix=ashci(beta.ash,level=0.95)

    CImatrix1=ashci(beta.ash,level=0.95,betaindex=c(1,2,5))
    CImatrix2=ashci(beta.ash,level=0.95,lfsr_threshold=0.1)

[Package ashr version 2.2-54 Index]