WINETASTER ON 05/09/18 WITH 8 JUDGES AND 7 WINES BASED ON RANKS, IDENT=N Copyright (c) 1995-2018 Richard E. Quandt, V. 1.65
A Tasting of Hermitage La Chapelle and Chave
FLIGHT 1: Number of Judges = 8 Number of Wines = 7
Identification of the Wine: The judges' overall ranking:
Wine A is La Chapelle 1989 ........ 6th place Wine B is J.L. Chave 1988 tied for 3rd place Wine C is La Chapelle 1988 tied for 3rd place Wine D is J.L. Chave 1989 ........ 1st place Wine E is La Chapelle 1983 ........ 5th place Wine F is La Chapelle 1990 ........ 7th place Wine G is La Chapelle 1982 ........ 2nd place
The Judges's Rankings
Judge Wine -> A B C D E F G Jerry 5. 1. 3. 2. 4. 6. 7. Mike 6. 5. 4. 1. 2. 3. 7. Orley 6. 5. 7. 2. 3. 4. 1. Ed 4. 3. 5. 6. 2. 7. 1. Zaki 5. 6. 2. 3. 7. 4. 1. Bob 2. 1. 5. 3. 6. 7. 4. Burt 7. 5. 2. 4. 1. 6. 3. Dick 2. 3. 1. 6. 7. 5. 4.
Table of Votes Against Wine -> A B C D E F G
Group Ranking -> 6 3 3 1 5 7 2 Votes Against -> 37 29 29 27 32 42 28
( 8 is the best possible, 56 is the worst)
Here is a measure of the correlation in the preferences of the judges which ranges between 1.0 (perfect correlation) and 0.0 (no correlation):
W = 0.1027
The probability that random chance could be responsible for this correlation is rather large, 0.5530. Most analysts would say that unless this probability is less than 0.1, the judges' preferences are not strongly related. We now analyze how each taster's preferences are correlated with the group preference. A correlation of 1.0 means that the taster's preferences are a perfect predictor of the group's preferences. A 0.0 means no correlation, while a -1.0 means that the taster has the reverse ranking of the group. This is measured by the correlation R.
Correlation Between the Ranks of Each Person With the Average Ranking of Others
Name of Person Correlation R Jerry 0.0901 Burt 0.0714 Ed 0.0000 Bob -0.0187 Orley -0.2143 Zaki -0.2703 Mike -0.4286 Dick -0.4643
The wines were preferred by the judges in the following order. When the preferences of the judges are strong enough to permit meaningful differentiation among the wines, they are separated by -------------------- and are judged to be significantly different.
1. ........ 1st place Wine D is J.L. Chave 1989 2. ........ 2nd place Wine G is La Chapelle 1982 3. tied for 3rd place Wine B is J.L. Chave 1988 4. tied for 3rd place Wine C is La Chapelle 1988 5. ........ 5th place Wine E is La Chapelle 1983 6. ........ 6th place Wine A is La Chapelle 1989 --------------------------------------------------- 7. ........ 7th place Wine F is La Chapelle 1990 We now test whether the ranksums AS A WHOLE provide a significant ordering. The Friedman Chi-square value is 4.9286. The probability that this could happen by chance is 0.5530 We now undertake a more detailed examination of the pair-wise rank correla- tions that exist between pairs of judges. First, we present a table in which you can find the correlation for any pair of judges, by finding one of the names in the left hand margin and the other name on top of a column. A second table arranges these correlations in descending order and marks which is significantly positive significantly negative, or not significant. This may allow you to find clusters of judges whose rankings were particularly similar or particularly dissimilar. Pairwise Rank Correlations Correlations must exceed in absolute value 0.79 for significance at the 0.05 level and must exceed 0.71 for significance at the 0.1 level Jerry Mike Orley Jerry 1.000 0.429 -0.321 Mike 0.429 1.000 0.143 Orley -0.321 0.143 1.000 Ed -0.179 -0.536 0.321 Zaki -0.357 -0.286 0.214 Bob 0.500 -0.393 -0.143 Burt 0.107 0.286 0.250 Dick 0.071 -0.643 -0.750 Ed Zaki Bob Jerry -0.179 -0.357 0.500 Mike -0.536 -0.286 -0.393 Orley 0.321 0.214 -0.143 Ed 1.000 -0.107 0.250 Zaki -0.107 1.000 -0.107 Bob 0.250 -0.107 1.000 Burt 0.429 0.107 -0.393 Dick -0.036 0.321 0.393 Burt Dick Jerry 0.107 0.071 Mike 0.286 -0.643 Orley 0.250 -0.750 Ed 0.429 -0.036 Zaki 0.107 0.321 Bob -0.393 0.393 Burt 1.000 -0.286 Dick -0.286 1.000 Pairwise correlations in descending order 0.500 Jerry and Bob Not significant 0.429 Jerry and Mike Not significant 0.429 Ed and Burt Not significant 0.393 Bob and Dick Not significant 0.321 Orley and Ed Not significant 0.321 Zaki and Dick Not significant 0.286 Mike and Burt Not significant 0.250 Orley and Burt Not significant 0.250 Ed and Bob Not significant 0.214 Orley and Zaki Not significant 0.143 Mike and Orley Not significant 0.107 Jerry and Burt Not significant 0.107 Zaki and Burt Not significant 0.071 Jerry and Dick Not significant -0.036 Ed and Dick Not significant -0.107 Zaki and Bob Not significant -0.107 Ed and Zaki Not significant -0.143 Orley and Bob Not significant -0.179 Jerry and Ed Not significant -0.286 Mike and Zaki Not significant -0.286 Burt and Dick Not significant -0.321 Jerry and Orley Not significant -0.357 Jerry and Zaki Not significant -0.393 Bob and Burt Not significant -0.393 Mike and Bob Not significant -0.536 Mike and Ed Not significant -0.643 Mike and Dick Not significant -0.750 Orley and Dick Significantly negative
COMMENT: This was a remarkable tasting, not only because of the high quality of the wines, but also because of their utter similarity to one another. Unlike many other tastings, the wines did not seem to change appreciably during the tasting. Interestingly, the wine that received a grade of 100 from Parker scored worst in our tasting and was significantly inferior to the othyer wines. From a sample of 2, the Chave wines were preferred to the La Chapelles. Overall a most memorable tasting.
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