logrankSingleZ: Helper function computes single component of the logrank...

In safestats: Safe Anytime-Valid Inference

Helper function computes single component of the logrank statistic

Description

Helper function computes single component of the logrank statistic

Usage

logrankSingleZ(obs0, obs1, y0, y1, ...)

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
...	further arguments to be passed to or from methods.

Value

Returns a list containing at least the following components:

oMinE

observed minus expected.

v

hypergeometric variance.

References

Grünwald, P. D., de Heide, R., & Koolen, W. (2024). Safe testing. Journal of the Royal Statistical Society. Series B (Methodological), 86(5), 1091-1128. (With discussions), https://doi.org/10.1093/jrsssb/qkae011. ter Schure, J., Pérez-Ortiz, M. F., Ly, A., & Grünwald, P. D. (2024). The Safe Logrank Test: Error control under continuous monitoring with unlimited horizon. The New England Journal of Statistics in Data Science, 2(2), 190-214, https://doi.org/10.51387/24-NEJSDS65.

Examples

y0Vector <- c(6, 4, 4, 1, 0)
y1Vector <- c(6, 6, 5, 2, 2)
obs0Vector <- c(1, 0, 2, 1, 0)
obs1Vector <- c(0, 1, 1, 0, 1)

varVector <- oMinEVector <-y0Vector

for (i in seq_along(y0Vector)) {
  tempResult <- logrankSingleZ(obs0=obs0Vector[i], obs1=obs1Vector[i],
                              y0=y0Vector[i], y1=y1Vector[i])
  oMinEVector[i] <- tempResult[["oMinE"]]
  varVector[i] <- tempResult[["v"]]
}

sum(oMinEVector)/sqrt(sum(varVector))

safestats documentation built on Sept. 6, 2026, 1:06 a.m.