Experimental Methods in Psychology

By Gustav Levine; Stanley Parkinson | Go to book overview
Save to active project

CHAPTER 8
Detection, Discrimination, and the Theory of Signal Detection

There are many situations in which it is important to identify conditions that aid in the successful detection of stimuli. One example is the design of radar screens. Another is the design of instrument panels on airplanes, which are usually crowded, and so have to be designed so that some critical signals stand out. Psychologists and human factors engineers are employed to test conditions that maximize successful detection. Psychologists are also interested in the more general questions about what conditions are good and bad for detection, and what are the quantitative relationships between stimulus changes and detectability (suggesting laws of perception).

An early detection question that was asked, which gave birth to a classic form of research, is the question of how weak a stimulus can be and still be detected. A similar question, concerning discrimination, is, how slight a difference between two stimuli can permit the two stimuli to be distinguished? Questions about detection and discrimination have become somewhat more sophisticated with time, but the two basic forms of research the initial questions suggested are still recognizable in current research designs.

Questions of detectability are generally examined in a large series of trials, in which a specified stimulus is either present or absent on each trial. On each trial a subject is asked to decide whether or not the stimulus is present. The question is how much of the stimulus is required for the subject to hear it, or see it, or taste it, etc. The

-204-

Notes for this page

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.
Loading One moment ...
Project items
Notes
Cite this page

Cited page

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

Cited page

Bookmark this page
Experimental Methods in Psychology
Table of contents

Table of contents

Settings

Settings

Typeface
Text size Smaller Larger
Search within

Search within this book

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?

While we understand printed pages are helpful to our users, this limitation is necessary to help protect our publishers' copyrighted material and prevent its unlawful distribution. We are sorry for any inconvenience.
Full screen
/ 476

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.

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.

Are you sure you want to delete this highlight?