Initial insights into the psychology of expertise arose from studies of agricultural workers. For instance, H. D. Hughes conducted one of the earliest studies of experts in 1917. He found that corn rated highest by expert corn judges did not produce the highest yield. Henry Wallace (later vice president under Franklin D. Roosevelt) reanalyzed Hughes's data using path analysis. He showed that (1) corn judges largely agreed with each other, but (2) their ratings correlated only slightly with crop yields.
In similar research, licensed grain inspectors were found to misgrade nearly one third of wheat samples and, when grading a second time, gave over one third a different grade. Also, increased experience made judges more confident but did not necessarily increase accuracy. Finally, more experi enced judges tended to overgrade wheat samples (perhaps the original "grade inflation").
One source of errors in agricultural judgment is the presence of irrelevant factors. Gary Gaeth and James Shanteau found that nondiagnostic material (e.g., excessive moisture) had a significant impact on decisions by soil judges. However, cognitive training successfully compensated for these irrelevant materials. Another approach to improving expert judgment was used in weather forecasting: Precipitation forecasts were improved using Brier scores (a quadratic scoring system). Recently, accuracy of short-term weather forecasts has increased dramatically.
Childs, A. W., & Melton, G. B. (1983). Rural psychology. New York: Plenum Press.
Husaini, B. A., Neff, J. A., & Stone, R. H. (1979). Psychiatric impairment in rural communities. Journal of Community Psychology, 7, 137-146.
Phelps, R. H., & Shanteau, J. (1978). Livestock judges: How much information can an expert use? Organizational Behavior and Human Performance, 21, 209-219.
James Shanteau Kansas State University
Was this article helpful?