Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Jul;84(5):1726-1733.
doi: 10.3758/s13414-022-02474-7. Epub 2022 Apr 28.

How much time does it take to discriminate two sets by their numbers of elements?

Jüri Allik  1   2 , Aire Raidvee  3
Affiliations

How much time does it take to discriminate two sets by their numbers of elements?

Jüri Allik et al. Atten Percept Psychophys. 2022 Jul.

Abstract

The ability to evaluate the number of elements in a set-numerosity-without symbolic representation is a form of primitive perceptual intelligence. A simple binomial model was proposed to explain how observers discriminate the numerical proportion between two sets of elements distinct in color or orientation (Raidvee et al., 2017, Attention Perception & Psychophysics, 79[1], 267-282). The binomial model's only parameter β is the probability with which each visual element can be noticed and registered by the perceptual system. Here we analyzed the response times (RT) which were ignored in the previous report since there were no instructions concerning response speed. The relationship between the mean RT and the absolute difference |ΔN| between numbers of elements in two sets was described by a linear regression, the slope of which became flatter as the total number of elements N increased. Because the coefficients of regression between the mean RT and |ΔN| were more directly related to the binomial probability β rather than to the standard deviation of the best fitting cumulative normal distribution, it was regarded as evidence that the binomial model with a single parameter - probability β - is a viable alternative to the customary Thurstonian-Gaussian model.

Keywords: Binomial model of discrimination; Numerosity discrimination; Psychometric discrimination function; Response time; Thurstonian psychophysics.

PubMed Disclaimer

References

    1. Allik, J., & Tuulmets, T. (1991). Occupancy model of perceived numerosity. Perception & Psychophysics, 49(4), 303–314. https://doi.org/10.3758/BF03205986 - DOI
    1. Allik, J., & Tuulmets, T. (1993). Perceived numerosity of spatiotemporal events. Perception & Psychophysics, 53(4), 450–459. https://doi.org/10.3758/BF03206789 - DOI
    1. Allik, J., Tuulmets, T., & Vos, P. G. (1991). Size invariance in visual number discrimination. Psychological Research—Psychologische Forschung, 53(4), 290–295. https://doi.org/10.1007/BF00920482 - DOI
    1. Anobile, G., Cicchini, G. M., & Burr, D. C. (2014). Separate mechanisms for perception of numerosity and density. Psychological Science, 25(1), 265–270. https://doi.org/10.1177/0956797613501520 - DOI - PubMed
    1. Anobile, G., Turi, M., Cicchini, G., & Burr, D. (2015). Mechanisms for perception of numerosity or texture-density are governed by crowding-like effects. Journal of Vision, 15, 4–4. https://doi.org/10.1167/15.5.4 - DOI - PubMed