Perceptual Structure in the Absence of Grounding for LLMs: The Impact of
  Abstractedness and Subjectivity in Color Language
Pablo Loyola Edison Marrese-Taylor Andres Hoyos-Idobro
The need for grounding in language understanding is an active research topic.
Previous work has suggested that color perception and color language appear as
a suitable test bed to empirically study the problem, given its cognitive
significance and showing that there is considerable alignment between a defined
color space and the feature space defined by a language model. To further study
this issue, we collect a large scale source of colors and their descriptions,
containing almost a 1 million examples , and perform an empirical analysis to
compare two kinds of alignments: (i) inter-space, by learning a mapping between
embedding space and color space, and (ii) intra-space, by means of prompting
comparatives between color descriptions. Our results show that while color
space alignment holds for monolexemic, highly pragmatic color descriptions,
this alignment drops considerably in the presence of examples that exhibit
elements of real linguistic usage such as subjectivity and abstractedness,
suggesting that grounding may be required in such cases.