The Application of Rasch Scaling to Wine Judging

The training of judges in sport and in industry is a challenging educational problem and recent developments in educational measurement can contribute to the resolution of this problem. The results of the judging of 98 wines from one class of a prominent Australian wine show were analysed using Rasch scaling. The raw scores were out of 20, graduated in steps of half a point, giving a total of 41 different scores. It was necessary to reduce this scale to an eight point scale, making all scores below 12.5 zero and compressing the remaining scores into seven scores from one to seven with each score combining two of the raw scores. It was found that this compression process does not adversely affect the analysis. This suggests that the traditional judging process tries to apply too fine a scoring system.