WINETASTER ON 03/03/03 WITH 8 JUDGES AND 8 WINES BASED ON RANKS, IDENT=N Copyright (c) 1995-2003 Richard E. Quandt, V. 1.65
FLIGHT 1: Number of Judges = 8 Number of Wines = 8
Identification of the Wine: The judges' overall ranking:
Wine A is Ch. Talbot 1996 ........ 2nd place Wine B is Ch. Montrose 1997 ........ 5th place Wine C is Ch. Calon Segur 1996 tied for 6th place Wine D is Ch. Pape Clement 1997 ........ 1st place Wine E is Ch. Talbot 1997 ........ 3rd place Wine F is Ch. Montrose 1996 ........ 8th place Wine G is Ch. Pape Clement 1996 ........ 4th place Wine H is Ch. Calon Segur 1997 tied for 6th place
The Judges's Rankings
Judge Wine -> A B C D E F G H Ed 4. 5. 7. 3. 2. 6. 1. 8. Burt 7. 3. 6. 1. 2. 4. 8. 5. Frank 1. 8. 2. 3. 4. 6. 5. 7. Orley 3. 1. 7. 6. 2. 4. 8. 5. Bob 3. 1. 7. 5. 4. 8. 6. 2. John 4. 6. 1. 2. 7. 8. 3. 5. Grant 1. 8. 7. 2. 5. 6. 3. 4. Dick 4. 5. 7. 2. 3. 6. 1. 8.
Table of Votes Against Wine -> A B C D E F G H
Group Ranking -> 2 5 6 1 3 8 4 6 Votes Against -> 27 37 44 24 29 48 35 44
( 8 is the best possible, 64 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 = 0.2039
The probability that random chance could be responsible for this correlation is rather large, 0.1214. 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 Correlation Price Dick 0.6429 0.2515 Ed 0.5952 0.3114 Grant 0.4286 0.0719 Frank 0.2635 0.7785 Bob 0.0952 -0.1916 Burt 0.0000 -0.3353 Orley -0.0240 -0.1078 John -0.0838 0.4791
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 Ch. Pape Clement 1997 --------------------------------------------------- 2. ........ 2nd place Wine A is Ch. Talbot 1996 3. ........ 3rd place Wine E is Ch. Talbor 1997 4. ........ 4th place Wine G is Ch. Pape Clement 1996 5. ........ 5th place Wine B is Ch. Montrose 1997 6. tied for 6th place Wine H is Ch. Calon Segur 1997 7. tied for 6th place Wine C is Ch. Calon Segur 1996 --------------------------------------------------- 8. ........ 8th place Wine F is Ch. Montrose 1996 We now test whether the ranksums AS A WHOLE provide a significant ordering. The Friedman Chi-square value is 11.4167. The probability that this could happen by chance is 0.1214
We now test whether the group ranking of wines is correlated with the prices of the wines. The rank correlation between them is 0.3494. At the 10% level of significance this would have to exceed the critical value of 0.5240 to be significant.
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 0.74 for significance at the 0.05 level and must exceed 0.64 for significance at the 0.1 level Ed Burt Frank Ed 1.000 0.048 0.238 Burt 0.048 1.000 -0.214 Frank 0.238 -0.214 1.000 Orley -0.048 0.452 -0.286 Bob -0.071 0.167 -0.333 John 0.048 -0.310 0.571 Grant 0.429 -0.214 0.524 Dick 0.976 0.071 0.262 Orley Bob John Ed -0.048 -0.071 0.048 Burt 0.452 0.167 -0.310 Frank -0.286 -0.333 0.571 Orley 1.000 0.595 -0.714 Bob 0.595 1.000 -0.167 John -0.714 -0.167 1.000 Grant -0.286 0.048 0.310 Dick -0.143 -0.095 0.167 Grant Dick Ed 0.429 0.976 Burt -0.214 0.071 Frank 0.524 0.262 Orley -0.286 -0.143 Bob 0.048 -0.095 John 0.310 0.167 Grant 1.000 0.500 Dick 0.500 1.000 Pairwise correlations in descending order 0.976 Ed and Dick Significantly positive 0.595 Orley and Bob Not significant 0.571 Frank and John Not significant 0.524 Frank and Grant Not significant 0.500 Grant and Dick Not significant 0.452 Burt and Orley Not significant 0.429 Ed and Grant Not significant 0.310 John and Grant Not significant 0.262 Frank and Dick Not significant 0.238 Ed and Frank Not significant 0.167 Burt and Bob Not significant 0.167 John and Dick Not significant 0.071 Burt and Dick Not significant 0.048 Bob and Grant Not significant 0.048 Ed and Burt Not significant 0.048 Ed and John Not significant -0.048 Ed and Orley Not significant -0.071 Ed and Bob Not significant -0.095 Bob and Dick Not significant -0.143 Orley and Dick Not significant -0.167 Bob and John Not significant -0.214 Burt and Frank Not significant -0.214 Burt and Grant Not significant -0.286 Frank and Orley Not significant -0.286 Orley and Grant Not significant -0.310 Burt and John Not significant -0.333 Frank and Bob Not significant -0.714 Orley and John Significantly negative
COMMENT: The group generally agreed that the 1997s were drinking better than the 1996s. Talbot and Pape Clement were clear winners among the chateaus. The wines had virtually no bouquet and the judging had to be done on factors other than the smell. The wines showed deep dark purple colors and are all too young to show good pronounced olfactory qualities. The wines have soft tannins, probably a result in part of good ripe grapes and possibly also of the new Bordeaux wine-making style, which is counter to conventional thinking about the 1996s.
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