mad.dist: MAD distances between objects

In cata: Analysis of Check-All-that-Apply (CATA) Data

MAD distances between objects

Description

Computes and returns inter-object median of absolute deviations (MADs) based differences.

Usage

mad.dist(X)

Arguments

X	objects-by-terms matrix

Value

object of class dist giving inter-object MAD distances

Author(s)

J.C. Castura

References

Chaya, C., Castura, J.C., & Greenacre, M.J. (2025). One citation, one vote! A new approach for analyzing check-all-that-apply (CATA) data using L1 norm methods. Food Quality and Preference, 134, 105639, \Sexpr[results=rd]{tools:::Rd_expr_doi("10.1016/j.foodqual.2018.09.006")}

Examples

CATA.freq <- apply(bread$cata, 2:3, sum)
# median-center columns (attributes)
CATA.swept <- sweep(CATA.freq, 2, apply(CATA.freq, 2, median))
# cluster analysis of products using complete linkage
dist.Products <- mad.dist(CATA.swept)
plot(as.dendrogram(hclust(dist.Products, method = "complete")), main = "Product clusters")
# cluster analysis of attributes using complete linkage
dist.Att <- mad.dist(t(CATA.swept))
plot(as.dendrogram(hclust(dist.Att, method = "complete")), main = "Attribute clusters")

cata documentation built on Sept. 12, 2025, 1:08 a.m.