R: Makes the Metropolis-Hastings acceptance decision, based upon...

decide {nimble} | R Documentation

## Makes the Metropolis-Hastings acceptance decision, based upon the input (log) Metropolis-Hastings ratio

### Description

This function returns a logical TRUE/FALSE value, indicating whether the proposed transition should be accepted (TRUE) or rejected (FALSE).

### Usage

    decide(logMetropolisRatio)

### Arguments

`logMetropolisRatio` | The log of the Metropolis-Hastings ratio, which is calculated from model probabilities and forward/reverse transition probabilities. Calculated as the ratio of the model probability under the proposal to that under the current values multiplied by the ratio of the reverse transition probability to the forward transition probability.

### Details

The Metropolis-Hastings accept/reject decisions is made as follows. If `logMetropolisRatio` is greater than 0, accept (return `TRUE`). Otherwise draw a uniform random number between 0 and 1 and accept if it is less that `exp(logMetropolisRatio`. The proposed transition will be rejected (return `FALSE`). If `logMetropolisRatio` is NA, NaN, or -Inf, a reject (`FALSE`) decision will be returned.

### Author(s)

Daniel Turek

[Package nimble version 0.10.0 Index]