Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 8 February 1974:
Vol. 183. no. 4124, pp. 482 - 488
DOI: 10.1126/science.183.4124.482
Prev | Table of Contents | Next

Articles

How Big Is a Chunk?

By combining data from several experiments, a basic human memory unit can be identified and measured

Herbert A. Simon 1

1 Carnegie-Mellon University. Pittsburgh, Pennsylvania 15213

I have explored some of the interactions between research on higher mental processes over the past decade or two and laboratory experiments on simpler cognitive processes. I have shown that, by viewing experimentation in a parameter-estimating paradigm instead of a hypothesis-testing paradigm, one can obtain much more information from experiments—information that, combined with contemporary theoretical models of the cognitive processes, has implications for human performance on tasks quite different from those of the original experiments.

The work of identifying and measuring the basic parameters of the human information processing system has just begun, but already important information has been gained. The psychological reality of the chunk has been fairly well demonstrated, and the chunk capacity of short-term memory has been shown to be in the range of five to seven. Fixation of information in longterm memory has been shown to take about 5 or 10 seconds per chunk.

Some other "magical numbers" have been estimated—for example, visual scanning speeds and times required for simple grammatical transformations—and no doubt others remain to be discovered. But even the two basic constants discussed in this article—short-term memory capacity and rate of fixation in long-term memory—organize, systematize, and explain a wide range of findings, about both simple tasks and more complex cognitive performances that have been reported in the psychological literature over the past 50 years or more.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
From the Cover: Conceptual knowledge increases infants' memory capacity.
L. Feigenson and J. Halberda (2008)
PNAS 105, 9926-9930
   Abstract »    Full Text »    PDF »
Visual short-term memory operates more efficiently on boundary features than on surface features.
G. A. ALVAREZ and P. CAVANAGH (2008)
Atten Percept Psychophys 70, 346-364
   Abstract »    PDF »
Clinical Reasoning in Experienced Nurses.
B. Simmons, D. Lanuza, M. Fonteyn, F. Hicks, and K. Holm (2003)
West J Nurs Res 25, 701-719
   Abstract »    PDF »
Effects of Time Scale Focus on System Understanding in Decision Support Systems.
D. N. Ford and D. E. M. McCormack (2000)
Simulation Gaming 31, 309-330
   Abstract »    PDF »
Improving Clinical Communication: A View from Psychology.
J. Parker and E. Coiera (2000)
JAMIA 7, 453-461
   Abstract »    Full Text »    PDF »
Brand Management in Hospitality: An Empirical Test of the Brisoux-Laroche Model.
M. Laroche and H. G. Parsa (2000)
Journal of Hospitality & Tourism Research 24, 199-222
   Abstract »    PDF »
Relationship Marketing in Consumer Markets: Antecedents and Consequences.
J. N. Sheth and A. Parvatlyar (1995)
Journal of the Academy of Marketing Science 23, 255-271
   Abstract »
Guidelines For Computer-Assisted Group Problem Solving: Meeting the Challenges of Complex Issues.
B. J. Broome and M. Chen (1992)
Small Group Research 23, 216-236
   Abstract »
Learning with Media.
R. B. Kozma (1991)
Review of Educational Research 61, 179-211
   Abstract »    PDF »
Next Generation Group Facilitation: Proposed Principles.
B. J. Broome and D. B. Keever (1989)
Management Communication Quarterly 3, 107-127
   Abstract »
Interpretive structural modelling: a methodology for structuring complex issues.
F.R. Janes (1988)
Transactions of the Institute of Measurement and Control 10, 145-154
   Abstract »    PDF »
Learning and Instruction: An Examination of Four Research Perspectives in Science Education.
B.-S. Eylon and M. C. Linn (1988)
Review of Educational Research 58, 251-301
   Abstract »    PDF »
The Role of Strategies in the Development of Memory Span Assessed by Running Probes.
G. S. Halford, M. T. Maybery, and D. Bennet (1985)
International Journal of Behavioral Development 8, 301-312
   Abstract »    PDF »
MEMORY PROCESSES IN MEDIA EFFECTS.
K. KELLERMANN (1985)
Communication Research 12, 83-131
   Abstract »
Conserving Thermal Energy and Social Integrity in the Newborn.
M. A. Newport, D. Diers, B. Holaday, and T. Tripp-Reimer (1984)
West J Nurs Res 6, 175-199
   PDF »
Implications of Cognitive Theory for Instruction in Problem Solving.
N. Frederiksen (1984)
Review of Educational Research 54, 363-407
   Abstract »    PDF »
A Model of Decision Making: Treatment Choice in End-Stage Renal Disease.
R. B. DEBER, J. M. BARNSLEY, and I. BLIDNER (1982)
American Behavioral Scientist 25, 585-598
A FANTASY CONSTRUCT OF TELEVISION VIEWING.
T. R. LINDLOF (1982)
Communication Research 9, 67-112
   Abstract »
Issue Information and Connotation in Candidate Imagery: Evidence from a Laboratory Experiment.
D. F. Davis (1981)
International Political Science Review/ Revue internationale de science pol 2, 461-479
   Abstract »    PDF »
Expert and Novice Performance in Solving Physics Problems.
J. Larkin, J. McDermott, D. P. Simon, and H. A. Simon (1980)
Science 208, 1335-1342
   Abstract »    PDF »
Traveler Evoked, Inept, and Inert Sets of Vacation Destinations.
A. G. Woodside and D. Sherrell (1977)
Journal of Travel Research 16, 14-18
   Abstract »    PDF »
Perspectives On a Consumer Information Processing Research Program.
J. Jacoby (1975)
Communication Research 2, 203-215
   PDF »
1: Studies of Problem Solving, Judgment, and Decision Making: Implications for Educational Research.
L. S. Shulman and A. S. Elstein (1975)
Review of Research in Education 3, 3-42
   PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)