freq_table - Add chi_square

[mbcann01]

Figure out a way to get chi_square and other related info (e.g., expected_n) from a freq_table. May be an enhancement to freq_table, but it will probably be a separate function called on the results of a freq_table

• Make function wrappers that work statistics I commonly need into a dplyr pipeline (chi-square, fisher, ttest, even regression)
• Chi-square should not add onto freq_table. It should create a new separate stats table, but think of a way to make it easily transfer information about significance back and forth (e.g., joins).

Still need to:

• [x] One minimal example of Fisher's exact test
• [x] Add interpretations of confidence intervals section to the end of the descriptive analysis vignette - with citations
• [x] Finish the "bottom line" interpretation
• [x] Add interpretations with citations - Also write up 95% confidence interval
• [x] Write unit tests for freq_test
• [x] Document freq_test using Roxygen
• [x] Convert to proper vignette
• [x] Clean up code - check build

Then move on to #15

[mbcann01]

After you've added in hypothesis testing here and in #15, then change the version number for bfuncs to 0.3.

Add release: https://github.com/brad-cannell/bfuncs/releases

[mbcann01]

Interpretations.

• Start with "typical" interpretations
• Add notes from Greenland and Rothman after

[mbcann01]

Look into p-value functions and Bayesian confidence intervals.

[mbcann01]

Refs for CI's

• [x] Biostatistics
• [x] Fundamentals of Biostatistics
• [x] Modern Epidemiology
• [x] Greenland article

[mbcann01]

Left off at the beginning of bivariate analysis (310) in develop_freq_test.Rmd.

Remember, get an initial version of these functions working. Improve over time.

[mbcann01]

Done with version 1. I'd still like to add other tests as needed, and the ability to generate p-value functions.