The effects of routine strength on adaptation and information search in recurrent decision making.

The strength of decision routines was manipulated within a computer-controlled micro world simulation involving recurrent decision making. During a learning phase, participants were led to prefer a certain brand of an industrial good either about 15 times in a weak routine or about 30 times in a strong routine condition. In the test phase of Experiment 1, participants were confronted with changes in the microworld that rendered the routine obsolete. Routine maintenance over a series of repeated acquisition decisions was assessed as the major dependent variable. Although new information clearly suggested that a deviation from the routine would be beneficial, strong routine participants were more likely to maintain the routine compared to weak routine participants and a control group in which a comparable option (same outcome probabilities as the routine) carried an unfamiliar brand label. Experiment 2 investigated the effects of routine strength on information search. After having learned the routine, participants were asked to make one final decision involving the routine. The task was either framed as being similar to the learning task or as being novel. Before making the final decision, participants were asked to consider new information about the alternatives. Strong routine participants in the familiar task condition preferred information that favored the routine and avoided unfavorable information. If the task was framed as being novel, such confirmation biases disappeared completely. In contrast, weak routine participants exhibited a moderate confirmation bias in their searches independent from task framing. Copyright 2000 Academic Press.