This Endless Frame

Nominal Scaling of Print Substrates

On November 12, 2009 I presented the paper "Nominal Scaling of Print Substrates" at the 17th IS&T Color Imaging Conference in Albuquerque, NM.

The abstract for this paper is below :

Print substrates are often measured or characterized using optical measurements, such as spectra or colorimetric measurements. Specialized devices or techniques exist to measure other properties, such as thickness, surface roughness, fluorescence, opacity or gloss. However, these measurements are often disjoint and, with respect to color imaging requirements, they are often a secondary consideration. We present specific measurement data for a collection of digital commercial print substrates and explore the correlations of these measures and their general distributions. We then present the results of a nominal scaling experiment in which both the visual and tactile properties of 72 print substrates was evaluated by 21 subjects. These evaluations were based on unconstrained text descriptions of the samples. The analysis made use of techniques from corpus linguistics to determine multivariate clustering by keywords and by samples. This allows both a global view of the visual and tactile categorization schemes of the subjects, as well as specific pairing of print substrates deemed to be most similar by subjects. We conclude with a discussion of nominal scaling and it's relevance to perceptual categorization.

The full paper is here.

The results included the dendrogram below of the tactile and visual keywords used by participants to describe paper.

The slides for the presentation are here.

Slide 9 of this deck, includes a still unanswered question of why does Optical Radiation Measurements volume V have ratio scales being longer than other scales? I've sketched and simplified the figure below :

In retrospect, this question would have been better served by providing an alternative visualization. Below is a re-mixed version of figure 2 of ORM V :

Which is a hypothesis that nominal (categorical) scaling includes approximations of order, spacing and a local origin.

The scales have also all been drawn to be approximately the same length.