The halo effect is a phenomenon where people judge the general personality of a person based on the perception of one salient characteristic. The effect was first observed by Fredrick Lyman Wells in an article in 1907, and referred to as the “error of the halo” in an article written by Edward Thorndike in 1920.

Sources:

Wells, F. L. (1907) “A Statistical Study of Literary Merit“. Archives of Psychology (pp. 1-30)

Thorndike, E. L. (1920) “A Constant Error in Psychological Ratings“. Journal of Applied Psychology (pp. 25-29)