The hardware and bandwidth for this mirror is donated by dogado GmbH, the Webhosting and Full Service-Cloud Provider. Check out our Wordpress Tutorial.
If you wish to report a bug, or if you are interested in having us mirror your free-software or open-source project, please feel free to contact us at mirror[@]dogado.de.

Type: Package
Title: Computation of the p-Value for the Exact Conditional Cochran-Armitage Trend Test
Version: 0.1.1
Description: Provides functions for computing the one-sided p-values of the Cochran-Armitage trend test statistic for the asymptotic and the exact conditional test. The computation of the p-value for the exact test is performed using an algorithm following an idea by Mehta, et al. (1992) <doi:10.2307/1390598>.
Depends: R (≥ 3.6.0)
License: GPL-2 | GPL-3
LazyData: TRUE
RoxygenNote: 7.0.2
Suggests: testthat
NeedsCompilation: no
Packaged: 2020-06-25 13:26:34 UTC; edelmand
Author: Dominic Edelmann [aut, cre]
Maintainer: Dominic Edelmann <dominic.edelmann@dkfz-heidelberg.de>
Repository: CRAN
Date/Publication: 2020-06-25 15:40:14 UTC

Asymptotic Cochran-Armitage trend test

Description

catt_asy calculates the Cochran-Armitage trend test statistic (Cochran (1954), Armitage (1955)) and the one-sided p-value for the corresponding asymptotic test. The exact form of used test statistic can be found in the paper by Portier and Hoel (1984).

Usage

catt_asy(dose.ratings, totals, cases)

Arguments

dose.ratings

A vector of dose ratings, the i-th entry corresponds to the dose-rating of the i-th group. This vector must be strictly monotonically increasing

totals

The vector of total individuals per group, the i-th entry corresponds to the total number of individuals in the i-th group

cases

The vector of incidences per groups, the i-th entry corresponds to the number of incidences in the i-th group

Value

A list containing the value of the Cochran-Armitage Trend Test Statistic and its asymptotic p-value.

References

Armitage, P. Tests for linear trends in proportions and frequencies. Biometrics, 11 (1955): 375-386.

Cochran, W. G. Some methods for strengthening the common \chi^2 tests, Biometrics. 10 (1954): 417-451.

Portier, C., and Hoel D. Type 1 error of trend tests in proportions and the design of cancer screens. Communications in Statistics-Theory and Methods, 13 (1984): 1-14.

Examples

d <- c(1,2,3,4)
n <- rep(20,4)
r <- c(1,4,3,8)

catt_asy(d, n, r)


Conditional exact Cochran-Armitage trend test

Description

catt_exact calculates the Cochran-Armitage trend test statistic (Cochran (1954), Armitage (1955)) and the one-sided p-value for the corresponding conditional exact test. The conditional exact test has been established by Williams (1988). The computation of its p-value is performed using an algorithm following an idea by Mehta, et al. (1992).

Usage

catt_exact(dose.ratings, totals, cases)

Arguments

dose.ratings

A vector of dose ratings, the i-th entry corresponds to the dose-rating of the i-th group. This vector must be strictly monotonically increasing

totals

The vector of total individuals per group, the i-th entry corresponds to the total number of individuals in the i-th group.

cases

The vector of incidences per groups, the i-th entry corresponds to the number of incidences in the i-th group.

Value

A list containing the value of the Cochran-Armitage Trend Test Statistic, its exact and asymptotic p-value.

References

Armitage, P. Tests for linear trends in proportions and frequencies. Biometrics, 11 (1955): 375-386.

Cochran, W. G. Some methods for strengthening the common \chi^2 tests, Biometrics. 10 (1954): 417-451.

Mehta, C. R., Nitin P., and Pralay S. Exact stratified linear rank tests for ordered categorical and binary data. Journal of Computational and Graphical Statistics, 1 (1992): 21-40.

Portier, C., and Hoel D. Type 1 error of trend tests in proportions and the design of cancer screens. Communications in Statistics-Theory and Methods, 13 (1984): 1-14.

Williams, D. A. Tests for differences between several small proportions. Applied Statistics, 37 (1988): 421-434.

Examples

d <- c(1,2,3,4)
n <- rep(20,4)
r <- c(1,4,3,8)

catt_exact(d, n, r)

These binaries (installable software) and packages are in development.
They may not be fully stable and should be used with caution. We make no claims about them.
Health stats visible at Monitor.