fitPriorParametersGPS: Prior Parameter Fit for the GPS
In bips-hb/pvm: PharmacoVigilance Methods

Description Usage Arguments Value References See Also Examples

Fits the prior parameters to the data for the Gamma Poisson shrinker (GPS). The initial guess for the parameter values are set the same as by DuMouchel (1999).

1 2	fitPriorParametersGPS(a, b, c, d, E = ((a + b) * (a + c))/(a + b + c + d), alpha1 = 0.2, beta1 = 0.1, alpha2 = 2, beta2 = 4, w = 1/3)

`a`	A vector with the counts of the upper left corner of the tables
`b`	A vector with the counts of the lower left corner of the tables
`c`	A vector with the counts of the upper right corner of the tables
`d`	A vector with the counts of the lower right corner of the tables
`alpha1`	Prior parameter α_1 (Default = 0.2)
`beta1`	Prior parameter β_1 (Default = 0.1)
`alpha2`	Prior parameter α_2 (Default = 2.0)
`beta2`	Prior parameter β_2 (Default = 4.0)
`w`	Prior parameter w (Default = 1/3)

A list with the prior parameters

DuMouchel, W. (1999). Bayesian Data Mining in Large Frequency Tables, with an Application to the FDA Spontaneous Reporting System. The American Statistician, 53(3), 177–190. https://doi.org/10.1080/00031305.1999.10474456

DuMouchel, W., & Pregibon, D. (2001). Empirical bayes screening for multi-item associations. Proceedings of the Seventh ACM SIGKDD International Conference on Knowledge Discovery and Data Mining - KDD ’01, (October), 67–76. http://doi.org/10.1145/502512.502526

loglikelihood2NegativeBinomial

a <- srdata$tables$a 
b <- srdata$tables$b 
c <- srdata$tables$c 
d <- srdata$tables$d 

fitPriorParametersGPS(a, b, c, d) 

# $alpha1
# [1] 98.28478
#
# $beta1
# [1] 16.48081
#
# $alpha2
# [1] 16.61439
#
# $beta2
# [1] 18.00642
#
# $w
# [1] 0.06132586