The Overconstraint of Response Time Models: Rethinking the Scaling Problem

By Donkin, Chris; Brown, Scott D. et al. | Psychonomic Bulletin & Review, December 2009 | Go to article overview

The Overconstraint of Response Time Models: Rethinking the Scaling Problem


Donkin, Chris, Brown, Scott D., Heathcote, Andrew, Psychonomic Bulletin & Review


Theories of choice response time (RT) provide insight into the psychological underpinnings of simple decisions. Evidence accumulation (or sequential sampling) models are the most successful theories of choice RT. These models all have the same "scaling" property-that a subset of their parameters can be multiplied by the same amount without changing their predictions. This property means that a single parameter must be fixed to allow the estimation of the remaining parameters. In the present article, we show that the traditional solution to this problem has overconstrained these models, unnecessarily restricting their ability to account for data and making implicit-and therefore unexamined-psychological assumptions. We show that versions of these models that address the scaling problem in a minimal way can provide a better description of data than can their over-constrained counterparts, even when increased model complexity is taken into account.

Many psychological experiments involve a choice between two alternatives. Despite their apparent simplicity, there are many complicated empirical regularities associated with the speed and accuracy of such choices. Response time (RT) distributions take on characteristic shapes that differ systematically, depending on whether the associated response is correct or incorrect, and depending on any number of experimental manipulations of stimulus properties or of instructions to the participants. A range of theories have been proposed to account for both choice probability and RT when making simple decisions (for reviews, see Luce, 1986; Ratcliff & Smith, 2004). Over the past 40 years, evidence accumulation (or "sequential sampling") models have dominated the debate about the cognitive processes underlying simple decisions (see, e.g., Busemeyer & Townsend, 1993; Ratcliff, 1978, Ratcliff & Smith, 2004; Smith, 1995; Stone, 1960; Usher & McClelland, 2001; Van Zandt, Colonius, & Proctor, 2000).

More recently, evidence accumulation models have been applied more widely, for example, as general tools to measure cognition in the manner of psychometrics (Schmiedek, Oberauer, Wilhelm, Süß, & Wittmann, 2007; Vandekerckhove, Tuerlinckx, & Lee, 2009; Wagenmakers, van der Maas, & Grasman, 2007), and as models for the neurophysiology of simple decisions (see, e.g., Forstmann et al., 2008; Ho, Brown, & Serences, 2009; Smith & Ratcliff, 2004). In light of this growing influence, it is especially important that users of these models are not misled by implicit-and hence unexamined-assumptions.

Evidence accumulation models all share a basic framework wherein, when making a decision, people repeatedly sample evidence from the stimulus. This evidence is accumulated until a threshold amount is reached, which triggers a decision response. These models naturally predict the response made (depending on which response has accumulated the most evidence) and the latency of the response (depending on how long the evidence took to accumulate). We illustrate these models using the example of a lexical decision task, in which a participant must decide whether a string of letters is a valid word (e.g., dog) or not (e.g., dxg). The participant samples information from the stimulus repeatedly and finds some evidence that suggests that the stimulus is a word, and other evidence to suggest that the stimulus is not a word. The participant accrues this information, waiting until there is enough evidence for one of the two options before responding. His or her choice corresponds to the response with the most evidence, and the time taken for this evidence to be accumulated is the response latency.

Over the past four or five decades, dozens of evidence accumulation models have been proposed, and all of them share a mathematical "scaling property": One can multiply a subset of their parameters by an arbitrary amount, without changing any of the model's predictions. …

The rest of this article is only available to active members of Questia

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items

Items saved from this article

This article has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited article

The Overconstraint of Response Time Models: Rethinking the Scaling Problem
Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Full screen

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.