Investigation of the Effect of Allowed and Forced Within-Trial Retasting on Judge Performance with the 2-AFC

Four experiments were conducted to examine the effect of retasting on judge performance with the 2-AFC. The first two experiments tested twenty-four subjects with NaCl solutions and eighteen subjects with bottled tea solutions, respectively. These experiments tested the sensory sampling model or SESAM (Juslin and Olsson 1997) prediction that judge performance will increase by the square-root of the number of times that the judge retastes. This was not valid for these experiments, although judge performance did improve with additional tasting. The second two experiments tested twenty subjects each with NaCl and bottled tea solutions, respectively. These experiments tested whether allowing retasting is advantageous for judge performance as concluded by Rousseau and O'Mahony (2000). This conclusion was confirmed. A further investigation found that judges who were poor discriminators benefited more from retasting than those who were good discriminators. Therefore, retasting should be allowed in order to improve judge performance.