truelies-package: truelies: Bayesian Methods to Estimate the Proportion of...

In truelies: Bayesian Methods to Estimate the Proportion of Liars in Coin Flip Experiments

Description

Implements Bayesian methods, described in Hugh-Jones (2019) <doi:10.1007/s40881-019-00069-x>, for estimating the proportion of liars in coin flip-style experiments, where subjects report a random outcome and are paid for reporting a "good" outcome.

Usage

To estimate the proportion of liars in an experiment, use update_prior() followed by dist_mean():

posterior <- update_prior(heads = 33, N = 50, P = 0.5, prior = dunif)
dist_mean(posterior)

To get confidence intervals for an estimate, use dist_hdr():

dist_hdr(posterior, conf_level = 0.95)

To test whether two different samples have the same proportion of liars, use difference_dist() followed by dist_hdr():

p2 <- update_prior(heads = 42, N = 49, P = 0.5, prior = dunif)
dd <- difference_dist(posterior, p2)
dist_hdr(dd, 0.95, bounds = c(-1, 1))

To test power for detecting a given proportion of liars, use power_calc():

power_calc(N = 100, P = 0.5, lambda = 0.2)

To test power for detecting differences between groups, use power_calc_difference():

power_calc_difference(N1 = 100, P = 5/6, lambda1 = 0.1, lambda2 = 0.25)

To compare different samples by empirical Bayes estimation, use empirical_bayes():

heads <- c(Baseline = 30, Treatment1 = 38, Treatment2 = 45)
N <- c(50, 52, 57)
result <- empirical_bayes(heads, N, P = 0.5)

Testing the package

To run tests on the package:

source(system.file("test-statistics.R", package = "truelies"))

You will need dplyr, purrr, tidyr and ggplot2 installed.

This will take some time and will produce data frames of test results for different parameter values, along with some plots.

Author(s)

David Hugh-Jones

References

Hugh-Jones, David (2019). True Lies: Comment on Garbarino, Slonim and Villeval (2018). Journal of the Economic Science Association. https://link.springer.com/article/10.1007/s40881-019-00069-x.

See Also

Useful links:

• https://github.com/hughjonesd/truelies

• Report bugs at https://github.com/hughjonesd/truelies/issues

truelies documentation built on Aug. 27, 2019, 1:02 a.m.