This study considers factors that influence whether decision-aid users direct decision aid recommendations toward their prior beliefs. Desiring to confirm their beliefs, decision aid users may seek to direct decision aid recommendations toward their prior opinions. Cognitive dissonance theory suggests that this is more likely to occur when users are strongly committed to their opinions. However, if decision-makers receive guidance from a decision aid, they may be less likely to direct decision aid recommendations toward their prior belief. In the first of two experiments, professional auditors were more likely to direct decision aid recommendations if they were committed to a decision before using the aid. In the second experiment, graduate business students were more likely to accept a decision aid's initial recommendation when the decision aid provided guidance. However, the decision aid guidance did not stop users from directing the decision aid recommendation toward their prior belief; rather, it appeared to influence users who otherwise would have shifted away from both the decision aid recommendation and their own prior belief. This study contributes to research on decision aid use by finding that both professional and nonprofessional decision aid users direct decision aid recommendations toward their prior belief, and that they are influenced by the degree of their decision commitment and the guidance they receive from the decision aid.
In March 1942, the Japanese naval staff began to plan a campaign designed to draw the United States navy into a decisive battle near the Pacific island of Midway. The campaign had been proposed by Admiral Matome Ugaki in January. As part of the planning, the naval staff conducted a simulation to determine the feasibility of the plan. Admiral Ugaki refereed the simulation. As a strong supporter of the campaign, "... he allowed nothing to happen which would seriously inconvenience the smooth development of the war games to their predestined conclusion. He did not scruple to override unfavorable rulings of other umpires." (Prange, et. al., 1982, p. 31)
The battle simulation used to plan the battle of Midway is an example of using a decision aid, a tool used to assist its user in improving a decision. Decision aids are used in a variety of contexts, including medical diagnosis, bankruptcy prediction, and audit tasks. Research on decision aids has investigated whether they yield superior judgments (Dawes, Faust and Meehl 1989) and, especially in the accounting domain, whether and why decision makers decide whether to rely and decision aid decision recommendations.
As Admiral Ugaki's war game suggests, a user may face more choices than to rely or not on an aids recommendation. A user may control the aid's result so that it is consistent with his or her own opinion. Research in accounting suggests that auditors control a decision aid results to concur with their personal opinion (Kachelmeier and Messier, 1990; Messier, Kachelmeier and Jensen, 2001). Organizations implement decision aids to guide or direct a decision process (Silver, 1990); understanding why people control decision aid recommendations and how this behavior effects decisions will help an organization match its decision support technology to its strategy. For an aid that is designed to guide decisions to add value to an organization, the aid should produce a different decision than an unaided judgment. By controlling a decision aid's recommendation to confirm a prior belief, users obtain the same decision as they would without use of the aid and diminish the aid's value. Decision aids are expensive to develop and often fall into disuse (Gill 1995). Whenever an organization implements a decision aid, it faces the threat that the aid's users will circumvent the aid's recommendation to rely on their own judgment.
This paper builds upon Kachelmeier and Messier (1990) to investigate why people control decision aid results and the effectiveness of strategies to reduce decision aid controlling. An experiment with CPA participants tests whether decision commitment, a construct drawn from social psychology (Festinger, 1957), increases how much users control decision aid recommendations, and an experiment with MBA student participants tests whether using decision aid explanations reduces the extent that users control decision aid recommendations. The results partially support that decision commitment influences controlling decision aid recommendations and support that decision aid explanations reduces controlling decision aid recommendations.
THEORY AND HYPOTHESES
Decision aids usually improve decision results (Dawes, Faust and Meehl, 1989), but decision makers often choose to rely upon their own judgment rather than upon an aid's recommendation. Incentives, feedback, and justification requirements decrease reliance on decision aids (Ashton, 1990). Experienced or confident decision makers believe that their ability is adequate and are less likely to rely upon decision aids than less experienced users (Arkes, Dawes and Christensen, 1986; Whitecotton, 1996). Decision makers who are informed about the decision aid algorithm or who are able to interact with the aid have greater confidence in the aid and feel more in control of the decision process, and are more likely to rely upon the aid (Davis, 1998; Eining, Jones and Loebbecke, 1997).
The decision aid reliance research cited above examines decision aids with inputs provided by the researcher and measures reliance as the difference between decision aid recommendations and decision aid users' decisions. In comparing human judgment to decision aid effectiveness, however, people are found to be better at measuring variables whereas decision aids are better at combining those inputs into a combined judgment (Klienmuntz, 1990). In practice decision aids often consist of subjective inputs based on users' judgment that are combined by the aid to arrive at a recommended coursed of action (e.g., Shelton, Whittington and Landsittel, 2001). Allowing users to decide the inputs of a decision aid may substantially alter how a decision aid is used. When the aid inputs are set externally to the user, the user is faced with either accepting the aid's recommendation or not accepting the recommendation. An aid that allows users to decide the inputs allows the user to use a decision aid recommendation to confirm their prior belief or to reach a strategic recommendation by setting the inputs.
Researchers in social psychology have long noted that people manage evidence based on their prior beliefs or social pressure (Festinger, 1957). Theories developed as a result of these observations provides a framework that describes a lack of reliance on decision aids, including managing an aid to get an expected result. These theories predict that people will use evidence to confirm beliefs to which they are strongly committed or to which they feel social pressure to conform. People search for or interpret evidence to support committed beliefs, opinions, or decisions, rather than rationally combine the evidence in the decision or belief-formulation process. If we regard a decision aid's recommendation as a piece of evidence for a decision-maker to consider, then we can investigate how the recommendation is treated as any other type of evidence is investigated.
The theory …