ABC_P2_gamma {ABCp2}

ABC Estimation of P2 for Gamma Distribution

Description

This function fits offspring data to a special case of the gamma distribution, in which zero values of offspring are excluded and all values are rounded to a whole number, and estimates P2 based on that distribution and the specificed priors.

Usage

ABC_P2_gamma(n, ObsMean, S_Lo, S_Hi, R_Lo, R_Hi, delta, iter)

Arguments

n

number of observations.

ObsMean

the observed mean number of offspring sired by the second male.

S_Lo

minimum shape value for the distribution.

S_Hi

maximum shape value for the distribution.

R_Lo

minimum rate value for the distribution.

R_Hi

maximum rate value for the distribution.

delta

maximum allowed difference between the estimated mean and observed mean number of offspring produced by the second male.

iter

number of iterations used to build the posterior.

Value

posterior

Posterior distribution of P2 values.

Shape

Vector of values for the shape parameter.

Rate

Vector of values for the rate parameter.

Author(s)

M. Catherine Duryea, Andrew D. Kern, Robert M. Cox, and Ryan Calsbeek

Examples

#Fit the Shape and Rate hyperpriors to a distribution of offspring. 

data(fungus)
fit_dist_gamma(fungus$Total_Offspring)

#Use hyperiors and priors calculated from the data to estimate P2. 
#Plot the saved distributions for the Shape and Rate parameters.
#Adjust, if necessary.

fungus_P2<-ABC_P2_gamma(12, 9.9, 1.14, 2.52, 0.06, 0.18, 0.1, 100)
hist(fungus_P2$posterior)
hist(fungus_P2$Shape)
hist(fungus_P2$Rate)