A Constant Error in Psychological Ratings
Edward Thorndike · 1920
"A single positive or negative trait we notice about a person unconsciously colors our judgment of their unrelated traits — so someone judged attractive, articulate, or physically impressive gets rated as more intelligent, competent, and trustworthy too, even absent any actual evidence for those separate qualities."
Thorndike's original study asked military commanding officers to rate soldiers across supposedly independent qualities: physique, intelligence, leadership, character. The ratings across these unrelated categories correlated far too strongly with each other to be measuring genuinely separate traits, suggesting the officers were forming one global impression, a halo, and letting it bleed into every specific rating rather than judging each quality independently.
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