When do individuals help close others improve? The role of information diagnosticity

On the basis of the self-evaluation maintenance model (SEM; Tesser, 1988), it was hypothesized that individuals give less improving information to relationally close (rather than distant) others, out of concern for being outperformed by close others in the future. Further, this effect only occurs if diagnostic and valid criteria for success are present. Three studies confirmed the hypotheses. In Studies 1 and 2, participants gave less improving information to familiar than to unfamiliar others in a domain (academics) in which diagnostic assessment criteria (grades) were available. This pattern was not found in a domain (social life) without diagnostic criteria. These results were replicated in Study 3, in which relative performance and diagnosticity of assessment criteria were manipulated and amount of improving information given to friends and strangers was measured. Diagnosticity of comparison information is an important addition to the SEM model.