Fractile assessments for a linear regression model: an experimental study

Garthwaite, P. H. (1989). Fractile assessments for a linear regression model: an experimental study. Organizational Behavior and Human Decision Processes, 43(2) pp. 188–206.



Subjects were questioned about four regression models in which the dependent variable (y) was linearly related to a single independent variable (x). Drawing graphs to help quantify their opinions, subjects assessed 0.25, 0.50, and 0.75 fractiles of their distributions for (a) the expected value of y at various x-values and (b) the expected change in y as x varied. Their opinions were generally underconfident with more than 60% of the interquartile ranges containing correct values. For task (a), proportions containing correct values were greater when x was toward the center of its range and for (b) they were greater when x varied over only a small part of its range. Both symmetric and asymmetric distributions were fitted to subjects' assessments and although assessments were sometimes markedly skew, a scoring rule judged the symmetric distributions to be slightly the more accurate.

Viewing alternatives


Public Attention

Altmetrics from Altmetric

Number of Citations

Citations from Dimensions
No digital document available to download for this item

Item Actions