6.8.2. statsmodels.sandbox.stats.contrast_tools

functions to work with contrasts for multiple tests

contrast matrices for comparing all pairs, all levels to reference level, ... extension to 2-way groups in progress

TwoWay: class for bringing two-way analysis together and try out various helper functions

Idea for second part - get all transformation matrices to move in between different full rank

parameterizations
  • standardize to one parameterization to get all interesting effects.

  • multivariate normal distribution - exploit or expand what we have in LikelihoodResults, cov_params, f_test,

    t_test, example: resols_dropf_full.cov_params(C2)

    • connect to new multiple comparison for contrast matrices, based on multivariate normal or t distribution (Hothorn, Bretz, Westfall)

6.8.2.1. Functions

contrast_all_one(nm) contrast or restriction matrix for all against first comparison
contrast_allpairs(nm) contrast or restriction matrix for all pairs of nm variables
contrast_diff_mean(nm) contrast or restriction matrix for all against mean comparison
contrast_labels(contrasts, names[, reverse])
contrast_product(names1, names2[, ...]) build contrast matrices for products of two categorical variables
dummy_1d(x[, varname]) dummy variable for id integer groups
dummy_limits(d) start and endpoints of groups in a sorted dummy variable array
dummy_nested(d1, d2[, method]) unfinished and incomplete mainly copy past dummy_product
dummy_product(d1, d2[, method]) dummy variable from product of two dummy variables
groupmean_d(x, d) groupmeans using dummy variables
signstr(x[, noplus])

6.8.2.2. Classes

DummyTransform(d1, d2) Conversion between full rank dummy encodings
TestContrastTools()
TwoWay(endog, factor1, factor2[, varnames]) a wrapper class for two way anova type of analysis with OLS