Shape-category taxonomy table

Return the full janusplot shape taxonomy as a data frame with four hierarchy columns plus presentation fields. The taxonomy is the single source of truth consumed by the classifier, the cell renderer, the legend plate, and the janusplot_data() output.

Hierarchy columns (finest → coarsest):

category

24-way fine label (linear_up, skewed_peak, bimodal, …). Computed per cell by janusplot().

code

Unique two-letter ASCII shorthand (safe on any font or typesetting pipeline) — e.g. lu for linear_up.

archetype

Seven-family grouping: monotone_linear, monotone_curved, unimodal, wave, multimodal, chaotic, degenerate.

monotonic

Three-way coarse classification: monotone / non_monotone / degenerate.

linear

Binary: linear / non_linear / degenerate.

The broader tiers (linear/non-linear, monotone/non-monotone) are textbook calculus; the archetype layer maps cleanly to shape-constrained regression vocabulary (Pya & Wood 2015; Meyer 2008) and to dose-response shape categories (Calabrese 2008; Calabrese & Baldwin 2001). The (T, I) dispatch underlying each fine category is a coarsened Morse-theoretic critical-point classification (Milnor 1963).

Usage

janusplot_shape_hierarchy()

Value

A data frame with 24 rows and columns category, code, archetype, monotonic, linear, glyph, ascii, label, gloss.

References

Calabrese, E. J. (2008). Hormesis: why it is important to toxicology and toxicologists. Environmental Toxicology and Chemistry, 27(7), 1451–1474.

Meyer, M. C. (2008). Inference using shape-restricted regression splines. Annals of Applied Statistics, 2(3), 1013–1033.

Milnor, J. (1963). Morse Theory. Princeton University Press.

Pya, N., & Wood, S. N. (2015). Shape constrained additive models. Statistics and Computing, 25(3), 543–559.

See also

Other shape-metrics: janusplot_shape_cutoffs(), janusplot_shape_metrics()

Examples

tax <- janusplot_shape_hierarchy()
head(tax[, c("category", "code", "archetype", "monotonic", "linear")])
#>       category code       archetype monotonic     linear
#> 1    linear_up   lu monotone_linear  monotone     linear
#> 2  linear_down   ld monotone_linear  monotone     linear
#> 3    convex_up   vu monotone_curved  monotone non_linear
#> 4   concave_up   cu monotone_curved  monotone non_linear
#> 5  convex_down   vd monotone_curved  monotone non_linear
#> 6 concave_down   cd monotone_curved  monotone non_linear
# Count how many categories live in each archetype
table(tax$archetype)
#> 
#>         chaotic      degenerate monotone_curved monotone_linear      multimodal 
#>               1               2               6               2               4 
#>        unimodal            wave 
#>               5               4