designA {ThurMod}

Create the Thurstonian design matrix for paired comparison and ranking data.

Description

Creates the Thurstonian design matrix for paired comparison and ranking data, given by blocks or the number of items.

Usage

designA(blocks = NULL, nitems = max(unique(blocks)))

Arguments

blocks

A matrix defining the blocks of the model. The number of rows must be the number of blocks, each row represents a block and contains the item numbers. The number of columns present the number of items per block.

nitems

The number of items that are included in the design.

Details

Each Thurstonian design can be defined by blocks of at least two items. The function determines the fundamental design matrix A of the Thurstonian design, including all possible paired comparisons that can be derived by the blocks. For further information of the importance of the design matrix, see Jansen and Schulze (2023a,2023b).

Value

Returns a design matrix which includes all paired comparisons derivable from the blocks.

References

Jansen, M. T., & Schulze, R. (2023a). Linear factor analytic Thurstonian forced-choice models: Current status and issues. Manuscript submitted.

Jansen, M. T., & Schulze, R. (2023b). The Thurstonian linked block design: Improving Thurstonian modeling for paired comparison and ranking data. Manuscript submitted.

Examples

# Define a matrix of blocks
blocks <- matrix(1:15,ncol=3, byrow=TRUE)

# Get the design matrix
loading_Matrix <- designA(blocks)