g.test {aspi}

Replicated G-tests of goodness-of-fit

Description

Perform replicated G-tests of goodness-of-fit to assess symmetry of parasitic infections.

Usage

g.test(x)

Arguments

x

a matrix or data frame with two numeric columns; first column is for left-side and 2nd column for right-side. Identifiers for hosts can be provided as row names.

Details

This function implements Sokal & Rohlf's (1995) G-test for the specific case of an expected 1:1 ratio The function takes as its argument a matrix or data frame with two numeric columns; first column is for left-side and 2nd column for right-side. Identifiers for hosts can be provided as row names. Uninfected hosts (zero count for both left and right sides) are ignored. Cannot be applied to data containing zero counts; use eb.test instead.

Value

A list containing two data.frames:

summary

results of total, heterogeneity and pooled G-tests. Data frame has four columns: test, degrees of freedom, G-statistic and p-value.

hosts

results of individual G-tests on distribution of parasites in each host. Data frame has seven columns: Host (ID), Left (count of parasites on left side), Right (count of parasites on right side), G (G-statistic), p (p-value), BH (p-value adjusted using Benjamini and Hochberg's procedure for controlling the false discovery rate) and Holm (p-value adjusted using Holm's method).

References

R.R. Sokal & F.J. Rohlf (1995) Biometry. 3rd Edition. New York: W.H. Freeman and Company. 887 pp.

Examples

g.test(diplostomum_eyes_excl_lenses)