Interactive decision-making: effects of consultation before personal decisions on postdecision consolidation.

Pre- and postdecision processes were studied in triads of participants, dyads of participants, and for individual decision-makers in two experiment (N = 57 and 50). Participants were students volunteering to take part in the study (21 men and 36 women with a mean age of 24 yr. and 25 men and 25 women with a mean age of 27 yr.). The purpose was to examine how much interactive versus individual social interaction (consultation with others before making a personal decision) affects postdecision consolidation. Predecision differentiation and postdecision consolidation have been defined as attractiveness changes over time in favour of the chosen alternative. Participants were coded into three categories (noncompensatory, compensatory, and nonclassified) according to their different decision strategies. For Exp. 1, postdecision consolidation effects were significant for participants who used a noncompensatory (no comparisons across attributes) decision strategy. For Exp. 2, postdecision consolidation effects were significant for participants who made a personal decision but not those who made an interactive decision. The differing results in these two experiments were discussed.