classify_seq: Cross-over design classification

In mjg211/xover: Design and analysis of cross-over clinical trials

Description

Classifies a cross-over design.

Usage

classify_seq(sequences, summary = T)

Arguments

sequences	An object of class xover_seq; a set of cross-over design sequences.
summary	A logical variable indicating whether a summary of the function's progress, and the identified classification, should be printed to the console. Defaults to T.

Details

classify_seq() supports the classification of a cross-over design (see sequences). Ultimately, the design will be assigned in to one of twelve possible categories. Briefly, a design is said to be a balanced block design if the following three conditions hold:

• Each treatment appears equally often in the design;

• The design is binary in the sense that each treatment appears in each block either n or n + 1 times, where n is an integer;

• The number of concurrences of treatments d₁ and d₂ is the same for all pairs of distinct treatment (d₁, d₂ ).

Here, the blocks are either rows or columns. A design that has less columns (rows) than treatments is said to be incomplete with respect to rows (columns). A design that is balanced with respect to both rows and columns is called a generalized Youden design (GYD). A GYD for which each treatment occurs equally often in each row (column) is called uniform on the rows (columns). If both conditions hold, it is called a generalized Latin Square. A design where each treatment occurs exactly once in each row and column is called a Latin Square. See the package vignette for details on these potential classifications.

Value

A list containing the following components

• classification: A character string describing the classification of the specified cross-over design.

• occurrences: A matrix describing the treatment occurrences.

• col_incidences: A matrix describing the treatment column incidences.

• row_incidences: A matrix describing the treatment row incidences.

• col_concurrences: A matrix describing the treatment column concurrences.

• row_concurrences: A matrix describing the treatment row concurrences.

Author(s)

Based on code from the crossdes package by Oliver Sailer.

See Also

The seq_#() functions within xover.

Examples

# Classify a three-treatment three-period Latin Square
latin    <- seq_latin(D = 3)
classify <- classify_seq(latin)

mjg211/xover documentation built on Oct. 16, 2019, 10:46 a.m.