Estimating Correlations from Scatterplots

Previous attempts to establish the function relating intuitive estimates of correlations from scatterplots to accepted statistical measures have led to unsatisfying results. In this study two experiments dealt with the effects of the statistical training of the viewer and various characteristics of the display on estimates. Statistical knowledge was related to higher estimates of correlations and the use of a wider range of values, but people with and without statistical knowledge were equally affected by the type of dispersion of the point cloud, the mere display of the regression line, and the slope of the regression line. Results indicate that estimates of correlations from scatterplots are partly based on perceptual processes that are influenced by visual properties of the display and are unrelated to the cognitive structures created by formal statistical training.

[1]  F. Mosteller,et al.  Eye-Fitting of Straight Lines. , 1981 .

[2]  J. Gibson The Ecological Approach to Visual Perception , 1979 .

[3]  F. J. Anscombe,et al.  Graphs in Statistical Analysis , 1973 .

[4]  David M. Lane,et al.  Judging the Relatedness of Variables: The Psychophysics of Covariation Detection , 1985 .

[5]  R. Strahan,et al.  Underestimating Correlation from Scatterplots , 1978 .

[6]  S. Lewandowsky,et al.  Discriminating strata in scatterplots , 1989 .

[7]  L. J. Chapman Illusory correlation in observational report. , 1967 .

[8]  Teresa M. Amabile,et al.  Judgment under uncertainty: Informal covariation assessment: Data-based versus theory-based judgments , 1982 .

[9]  C. Collyer,et al.  Psychology of the Scientist: LXIII. Perceiving Scattergrams: Is Visual Line Fitting Related to Estimation of the Correlation Coefficient? , 1990, Perceptual and motor skills.

[10]  L. J. Chapman,et al.  Genesis of popular but erroneous psychodiagnostic observations. , 1967, Journal of abnormal psychology.

[11]  Philip Bobko,et al.  THE PERCEPTION OF PEARSON PRODUCT MOMENT CORRELATIONS FROM BIVARIATE SCATTERPLOTS , 1979 .

[12]  Gerald V. Post,et al.  Density in scatterplots and the estimation of correlation , 1989 .

[13]  I. Pollack,et al.  Identification of visual correlational scatterplots. , 1960, Journal of experimental psychology.

[14]  W. Cleveland,et al.  Variables on Scatterplots Look More Highly Correlated When the Scales Are Increased , 1982, Science.

[15]  L. J. Chapman,et al.  Illusory correlation as an obstacle to the use of valid psychodiagnostic signs. , 1969, Journal of abnormal psychology.

[16]  W. S. Cleveland,et al.  Human factors and behavioral science: Experiments on quantitative judgments of graphs and maps , 1983, The Bell System Technical Journal.

[17]  L. Ross,et al.  Human Inference: Strategies and Shortcomings of Social Judgment. , 1981 .

[18]  Howard Wainer,et al.  On the Robustness of a Class of Naive Estimators , 1979 .