title: Efficacy = endowment x efficiency: revisiting efficacy and endowment effects in a public goods dilemma.
abstract: This article reexamines the efficacy and endowment effects in public good (PG) dilemma by conceptualizing that efficacy = endowment x efficiency. Endowment is the resource that a person can contribute. Efficiency is the impact of a unit of endowment. Efficacy is the total impact of contribution. The authors used a group project scenario to simulate a continuous contribution PG dilemma. The 2 x 2 x 2 x 2 experimental design manipulated own efficiency and own endowment as within-subject variables and the other persons' efficiency and endowment as between-subject variables. Results indicate that cooperation was mainly affected by one's endowment and others' efficiency. The authors distinguished among 3 types of efficiency effects: (a) an own-absolute-efficiency effect that efficient people put in more effort regardless of others' efficiency, (b) an other-absolute-inefficiency effect that people put in more effort when others are inefficient, and (c) a relative-inefficiency effect that inefficient people put in less effort in the presence of efficient people. Contrasting previous robust findings on efficiency, they identified a situation in which efficiency has no effects--when one has more endowment than do others.
authors.affiliation: Department of Psychology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
authors.forename: Chi-ching
authors.initials: CC
authors.lastname: Yu
authors.forename: Wing-tung
authors.initials: WT
authors.lastname: Au
authors.forename: Ka-shing Kevin
authors.initials: KS
authors.lastname: Chan
mesh_terms: D000704:Analysis of Variance; D003299:Cooperative Behavior; D004526:Efficiency / Q000502:physiology*; D005716:Game Theory; D006126:Group Processes; D006801:Humans; D007398:Interpersonal Relations; D020377:Self Efficacy; D012938:Social Perception; D013334:Students / Q000523:psychology; D011795:Surveys and Questionnaires; D013997:Time Factors