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What are the shapes of response time distributions in visual search?

ABSTRACT: Many visual search experiments measure response time (RT) as their primary dependent variable. Analyses typically focus on mean (or median) RT. However, given enough data, the RT distribution can be a rich source of information. For this paper, we collected about 500 trials per cell per observer for both target-present and target-absent displays in each of three classic search tasks: feature search, with the target defined by color; conjunction search, with the target defined by both color and orientation; and spatial configuration search for a 2 among distractor 5s. This large data set allows us to characterize the RT distributions in detail. We present the raw RT distributions and fit several psychologically motivated functions (ex-Gaussian, ex-Wald, Gamma, and Weibull) to the data. We analyze and interpret parameter trends from these four functions within the context of theories of visual search.

SUBMITTER: Palmer EM

PROVIDER: S-EPMC3062635 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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What are the shapes of response time distributions in visual search?

Palmer Evan M EM Horowitz Todd S TS Torralba Antonio A Wolfe Jeremy M JM

Journal of experimental psychology. Human perception and performance 20110201 1

Many visual search experiments measure response time (RT) as their primary dependent variable. Analyses typically focus on mean (or median) RT. However, given enough data, the RT distribution can be a rich source of information. For this paper, we collected about 500 trials per cell per observer for both target-present and target-absent displays in each of three classic search tasks: feature search, with the target defined by color; conjunction search, with the target defined by both color and o ...[more]

PMID: 21090905

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Project description:[This corrects the article DOI: 10.1371/journal.pone.0194640.].

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