Under-reliance on the Decision Aid: a Difference in Calibration and Attribution between Self and Aid

It is often assumed that two heads are better than one, but reliance on decision aids is often inappropriate. Decisions to rely on an aid are thought to be based on a comparison between the perceived reliability of own performance and that of the decision aid. Unfortunately, perceived reliabilities are unlikely to be perfectly calibrated. This may result in inappropriate decisions to rely on advice. In a laboratory experiment with 40 participants, we studied whether calibration improves after practice, whether calibration of own reliability differs from calibration of the aid’s reliability and whether unreliability of the aid is attributed differently. Under-trust in own reliability disappears after practice but under-trust in the aid’s reliability persists. Unreliability of the decision aid is less likely to be attributed to temporary, external and uncontrollable factors. This asymmetry in attribution and calibration may explain under-reliance on decision aids.