Color naming reflects optimal partitions of color space

Terry Regier; Paul Kay; Naveen Khetarpal

doi:10.1073/pnas.0610341104

New Research In

Contributed by Paul Kay, November 21, 2006 (received for review October 15, 2006)

Abstract

The nature of color categories in the world's languages is contested. One major view holds that color categories are organized around universal focal colors, whereas an opposing view holds instead that categories are defined at their boundaries by linguistic convention. Both of these standardly opposed views are challenged by existing data. Here, we argue for a third view based on a proposal by Jameson and D'Andrade [Jameson KA, D'Andrade RG (1997) in Color Categories in Thought and Language, eds Hardin CL, Maffi L (Cambridge Univ Press, Cambridge, U.K.), pp 295–319]: that color naming across languages reflects optimal or near-optimal divisions of an irregularly shaped perceptual color space. We formalize this idea, test it against color-naming data from a broad range of languages and show that it accounts for universal tendencies in color naming while also accommodating some observed cross-language variation.

Footnotes

^bTo whom correspondence may be addressed. E-mail: regier{at}uchicago.edu or paulkay{at}berkeley.edu
Author contributions: T.R. and P.K. designed research; T.R. and N.K. performed research; T.R. and N.K. analyzed data; and T.R. and P.K. wrote the paper.
The authors declare no conflict of interest.
↵ ^eThe WCS data, including genetic affiliation and other particulars about the languages, are available at http://www.icsi.berkeley.edu/wcs/data.html.
↵ ^fIn this mode map, as in some others reported here, there are a few isolated chips for which the modal color term was one that was not widely used; these chips are therefore colored differently from most others in the array (e.g. here, the light-blue and brown chips in columns 4–10).
↵ ^gCIEL*a*b* is a 3D space. The L* dimension corresponds to lightness, whereas the a* and b* dimensions define a plane orthogonal to L* such that the angle of a vector in that plane, rooted at the L* axis, corresponds to hue and the radius of such a vector corresponds to saturation. Despite this reference to polar coordinates in linking positions in the space to psychological quantities, the CIELAB distance metric is standard Euclidean distance. We converted our Munsell coordinates to CIELAB by using Wallkill Color Munsell conversion software, version 6.5.17, which assumes illuminant C, 2 degree standard observer.
↵ ^hAlthough all simulations are based on distances in 3D CIELAB space, we display the results as overlays of the actual 2D stimulus palette, which is based on the Munsell system. We display our results this way because the palette is widely used as a reference frame in the literature on color naming and cognition.
↵ ⁱThe rotation is in Munsell coordinates, although our well-formedness calculations are in CIELAB. We chose to rotate in this manner because it is simple to convey the idea with these displays and because doing so does not affect the logic of our argument.
Abbreviation:
WCS,
World Color Survey.
© 2007 by The National Academy of Sciences of the USA

Terry Regier ^a , ^b,
Paul Kay a , ^c , ^d, and
Naveen Khetarpal ^a

^aDepartment of Psychology, University of Chicago, 5848 South University Avenue, Chicago, IL 60637;
^cDepartment of Linguistics, University of California, Berkeley, CA 94720; and
^dInternational Computer Science Institute, 1947 Center Street, Berkeley, CA 94704

Contributed by Paul Kay, November 21, 2006 (received for review October 15, 2006)

Abstract

cognitive modeling
color categories
color terms
semantic universals

Footnotes

^bTo whom correspondence may be addressed. E-mail: regier{at}uchicago.edu or paulkay{at}berkeley.edu
Author contributions: T.R. and P.K. designed research; T.R. and N.K. performed research; T.R. and N.K. analyzed data; and T.R. and P.K. wrote the paper.
The authors declare no conflict of interest.
↵ ^eThe WCS data, including genetic affiliation and other particulars about the languages, are available at http://www.icsi.berkeley.edu/wcs/data.html.
↵ ^fIn this mode map, as in some others reported here, there are a few isolated chips for which the modal color term was one that was not widely used; these chips are therefore colored differently from most others in the array (e.g. here, the light-blue and brown chips in columns 4–10).
↵ ^gCIEL*a*b* is a 3D space. The L* dimension corresponds to lightness, whereas the a* and b* dimensions define a plane orthogonal to L* such that the angle of a vector in that plane, rooted at the L* axis, corresponds to hue and the radius of such a vector corresponds to saturation. Despite this reference to polar coordinates in linking positions in the space to psychological quantities, the CIELAB distance metric is standard Euclidean distance. We converted our Munsell coordinates to CIELAB by using Wallkill Color Munsell conversion software, version 6.5.17, which assumes illuminant C, 2 degree standard observer.
↵ ^hAlthough all simulations are based on distances in 3D CIELAB space, we display the results as overlays of the actual 2D stimulus palette, which is based on the Munsell system. We display our results this way because the palette is widely used as a reference frame in the literature on color naming and cognition.
↵ ⁱThe rotation is in Munsell coordinates, although our well-formedness calculations are in CIELAB. We chose to rotate in this manner because it is simple to convey the idea with these displays and because doing so does not affect the logic of our argument.
Abbreviation:
WCS,
World Color Survey.