logrankSingleEExact {safestats}

Helper function computes single component of the exact logrank e-value

Description

Helper function computes single component of the exact logrank e-value

Usage

logrankSingleEExact(obs0, obs1, y0, y1, thetaS, theta0 = 1, ...)

Arguments

obs0

integer, number of observations in the control group.

obs1

integer, number of observations in the treatment group.

y0

integer, total number of participants in the control group.

y1

integer, total number of participants in the treatment group.

thetaS

numeric > 0 represents the safe test defining (GROW) alternative hypothesis obtained from designSafeLogrank().

theta0

numeric > 0 represents the null hypothesis. Default theta0=1.

...

further arguments to be passed to or from methods.

Value

Returns a list containing at least the following components:

logP0

Log likelihood of Fisher's hypergeometric at the null

logEValueLess

Log likelihood of Fisher's hypergeometric at the alternative

logEValueGreater

Log likelihood of Fisher's hypergeometric at 1/alternative

Examples

#'
y0Vector <- c(5, 4, 3, 3, 2, 1)
y1Vector <- c(5, 5, 4, 2, 2, 0)
obs0Vector <- c(1, 1, 0, 1, 0, 1)
obs1Vector <- c(0, 0, 1, 0, 1, 0)

logEValueGreater <- logEValueLess <- vector("numeric", length(y0Vector))

for (i in seq_along(y0Vector)) {
  tempResult <- logrankSingleEExact(obs0=obs0Vector[i], obs1=obs1Vector[i],
                                    y0=y0Vector[i], y1=y1Vector[i],
                                    thetaS=0.7, theta0=1)
  logEValueLess[i] <- tempResult[["logEValueLess"]]
  logEValueGreater[i] <- tempResult[["logEValueGreater"]]
}

eValueLess <- exp(sum(logEValueLess))
eValueLess #1.116161
eValueGreater <- exp(sum(logEValueGreater))
eValueGreater # 0.7665818
eValue <- 1/2*eValueLess + 1/2*eValueGreater
eValue # 0.9413714