Specifies an inverse Gamma prior for a variance parameter, but inputs are defined in terms of a standard deviation.
SdPrior(sigma.guess, sample.size = .01, initial.value = sigma.guess,
fixed = FALSE, upper.limit = Inf)
A prior guess at the value of the standard deviation.
The weight given to sigma.guess
.
Interpretable as a prior observation count.
The initial value of the paramter in the MCMC algorithm.
Logical. Some algorithms allow you to fix sigma at a
particular value. If TRUE
then sigma will remain fixed at
initial.value
, if supported.
If positive, this is the upper limit on possible values of the standard deviation parameter. Otherwise the upper limit is assumed infinite. Not supported by all MCMC algorithms.
Steven L. Scott steve.the.bayesian@gmail.com
Gelman, Carlin, Stern, Rubin (2003), "Bayesian Data Analysis", Chapman and Hall.