Post-decision consolidation, as a function of the instructions to the decision maker and of the decision problem

The effects of instructions and decision problems on post-decision processes were studied by varying the instructions to subjects. Subjects made a medical policy decision based on information on four attributes in Experiments 1-2. The subjects were given different instructions: (1) no instruction at all about a second session, (2) instruction to remember his/her decision until a session a week later, and (3) instruction to justify the decision at a later occasion one week later. The results indicated post-decision consolidation in the first group, as predicted by the Differentiation and Consolidation Theory (Svenson, 1992). The effect showed up in attractiveness restructuring in support of the chosen alternative on the most important attributes. The instruction to remember the decision until a later time increased the consolidation effect. Contrary to our expectations, the instruction to later justify the decision did not produce any consolidation. This effect was replicated in the second experiment and could not be interpreted as a random result. In a third experiment the decision problem was framed as an environmental pollution problem and it was preceded by a carefully designed booklet presenting arguments for and against different materials used in manufacturing packages for coffee. Subjects were then asked to make a choice of the same coffee in two different packages. The data indicated no difference in structural consolidation as a result of the instruction to justify or not. The paper concludes with a discussion pointing out the importance of the involvement in a decision task for decision differentiation and consolidation.