An Adjusted Error Score Calculation for the Farnsworth-Munsell 100 Hue Test

ABSTRACT

The Farnsworth-Munsell 100 Hue Test, a test that measures an individual’s hue discrimination ability, operates with the fundamental assumption that it is administered using a fixed, standard illuminant. This assumption is violated when the testing illuminant is changed—as is common when testing color discrimination ability of an illuminant—which likely causes a reordering of the caps in the test. To ensure that a participant is not falsely penalized for correctly responding to a hue transposition caused by the new testing light source, an adjusted error score is proposed that reconciles light source–induced hue transpositions and participant performance on the test.

KEYWORDS:

• Adjusted total error score
• color discrimination
• Farnsworth-Munsell 100 Hue Test
• total light source error score
• transposition

Acknowledgments

The author thanks X-rite for supplying the spectral reflectance distributions of the caps of the FM-100 test and for granting permission to publish the supplemental calculator that accompanies this article. Also, the author gratefully acknowledges Kevin Houser for his help facilitating the discussion to acquire permission.

Supplemental material

An Excel spreadsheet, which performs the computations described herein, accompanies this manuscript and is available online and linked by the same DOI as this manuscript.

Disclosure statement

The author reported no declarations of interest.

Supplementary material

Supplemental data for this article can be accessed on the publisher’s website.

Notes

¹. For this equation to work properly, the terms |C_j − C_{j + 1}| and |C_j − C_{j − 1}| must each be equal to 1 when the caps are ordered correctly. Because the first free cap in tray A is numbered 85, not 1, the calculation requires a dummy array that assigns cap 85 a value of 1, cap 1 a value of 2, and so on.

². The cap error must be calculated for the end caps of the try; otherwise, results will be incorrect when errors are made near the tray’s ends; this necessitates the n + 2 term in the equation, the 2 accounting for each end cap.

Additional information

Funding

This work is derived from Esposito (2016) and Esposito and Houser (2017), funded by Project CANDLE partners: Cline Betteridge Bernstein Lighting Design, Digital Filaments, Domingo Gonzalez Associates, Eaton’s Cooper Lighting Business, Fisher Marantz Stone, Focal Point, Horton Lees Brogden Lighting Design, Lam Partners, Landscape Forms, Lighting Design Alliance, The Lighting Practice, Lutron Electronics, Naomi Miller, Office for Visual Interaction Inc., Philips Lighting, Randy Burkett Lighting Design, Schuler Shook, studio i, Tillotson Design Associates, and Traxon Technologies.