expectation-methods {coin}R Documentation

Extract the Expectation and Variance / Covariance of Linear Statistics

Description

Extracts the conditional expectation and covariance for linear statistics from objects inheriting from "IndependenceTest".

Usage

expectation(object, ...)
covariance(object, ...)
variance(object, ...)

Arguments

object an object inheriting from class IndependenceTest-class.
... further arguments (currently ignored).

Methods

expectation
extracts the expectation of the linear statistic of object.
covariance
extracts the covariance of the linear statistic of object.
variance
extracts the variance of the linear statistic of object.

Examples


  df <- data.frame(y = gl(3, 2), x = gl(3, 2)[sample(1:6)])

  ### Cochran-Mantel-Haenzel Test
  ct <- cmh_test(y ~ x, data = df)
 
  ### the linear statistic, i.e, the contingency table
  l <- statistic(ct, type = "linear")
  l

  ### expectation
  El <- expectation(ct)
  El

  ### covariance
  Vl <- covariance(ct)
  Vl

  ### the standardized contingency table (hard way)
  (l - El) / sqrt(variance(ct))

  ### easy way
  statistic(ct, type = "standardized")


[Package coin version 1.0-3 Index]