Confirmation Bias in a Simulated Research Environment: An Experimental Study of Scientific Inference

Abstract

Numerous authors (e.g., Popper, 1959) argue that scientists should try to falsify rather than confirm theories. However, recent empirical work (Wason and Johnson-Laird, 1972) suggests the existence of a confirmation bias, at least on abstract problems. Using a more realistic, computer controlled environment modeled after a real research setting, subjects in this study first formulated hypotheses about the laws governing events occurring in the environment. They then chose between pairs of environments in which they could: (I) make observations which would probably confirm these hypotheses, or (2) test alternative hypotheses. Strong evidence for a confirmation bias involving failure to choose environments allowing tests of alternative hypotheses was found. However, when subjects did obtain explicit falsifying information, they used this information to reject incorrect hypotheses.

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References

Fulton

D. L.

(1974). A plasma-panel interactive graphic system. Proceedings of the Society for Information Display 15, 74–80.

Hume

(1955). An Inquiry Concerning Human Understanding New York: Bobbs-Merrill.

Johnson-Laird

P. N.

Legrenzi

M. S.

(1972). Reasoning and a sense of reality. British Journal of Psychology 63, 395–400.

Kuhn

T. S.

(1970). The Structure of Scientific Revolutions 2nd ed. Chicago: University of Chicago Press.

Miller

G. A.

(1967). Project Grammarama. The Psychology of Communication New York: Basic Books.

Mitroff

I. I.

(1974). The Subjective Side of Science Amsterdam: Elsevier Scientific Publishing Co.

Platt

J. R.

(1964). Strong inference. Science 146, 347–353.

Popper

K. R.

(1959). The Logic of Scientific Discovery New York: Basic Books.

Popper

K. R.

(1962). Conjectures and Refutations New York: Basic Books.

10.

Salmon

(1967). The Foundations of Scientific Inference Pittsburgh: University of Pittsburgh Press.

11.

Wason

P. C.

(1960). On the failure to eliminate hypotheses in a conceptual task. Quarterly Journal of Experimental Psychology 12, 129–140.

12.

Wason

P. C.

(1968a). Reasoning about a rule. Quarterly Journal of Experimental Psychology 20, 273–281.

13.

Wason

P. C.

(1968b). On the failure to eliminate hypotheses in a conceptual task: a second look. In Johnson-Laird

P. N.

Wason

P. C.

(Eds), Thinking and Reasoning Baltimore: Penguin Books.

14.

Wason

P. C.

(1971). Problem solving and reasoning. Cognitive Psychology Summerfield

British Medical Bulletin. 27, 206–210.

15.

Wason

P. C.

Johnson-Laird

P. N.

(1972). Psychology of Reasoning: Structure and Content Cambridge, MA: Harvard University Press.