WINETASTER ON 11/18/96 WITH 7 JUDGES AND 8 WINES BASED ON RANKS, IDENT=N Copyright (c) 1995-2011 Richard E. Quandt, V. 1.65
FLIGHT 1: Number of Judges = 7 Number of Wines = 8
Identification of the Wine: The judges' overall ranking:
Wine A is Ch. Haut Brion 1983 ........ 3rd place Wine B is Ch. Calons Segur 1983 ........ 8th place Wine C is Ch. Palmer 1983 ........ 4th place Wine D is Ch. Cheval Blanc 1983 ........ 1st place Wine E is Ch. Beychevelle 1983 ........ 2nd place Wine F is Clos de Jacobins 1983 ........ 7th place Wine G is Ch. Rausan Segla 1983 ........ 5th place Wine H is Ch. Lafite 1983 ........ 6th place
The Judges's Rankings
Judge Wine -> A B C D E F G H John 1. 8. 7. 2. 4. 3. 5. 6. Ken 8. 7. 5. 6. 2. 3. 1. 4. Burt 2. 3. 1. 5. 4. 8. 6. 7. Bob 1. 4. 2. 3. 5. 8. 7. 6. Orley 6. 8. 7. 1. 2. 3. 5. 4. Ed 7. 8. 4. 1. 2. 5. 3. 6. Dick 3. 5. 4. 1. 8. 7. 6. 2.
Table of Votes Against Wine -> A B C D E F G H
Group Ranking -> 3 8 4 1 2 7 5 6 Votes Against -> 28 43 30 19 27 37 33 35
( 7 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 = 0.1788
The probability that random chance could be responsible for this correlation is rather large, 0.2702. 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 Ed 0.5238 John 0.4192 Orley 0.3333 Bob 0.2156 Dick 0.1429 Burt -0.0359 Ken -0.2994
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. Cheval Blanc 1983 --------------------------------------------------- 2. ........ 2nd place Wine E is Ch. Beychevelle 1983 3. ........ 3rd place Wine A is Ch. Haut Brion 1983 4. ........ 4th place Wine C is Ch. Palmer 1983 5. ........ 5th place Wine G is Ch. Rausan Segla 1983 6. ........ 6th place Wine H is Ch. Lafite 1983 7. ........ 7th place Wine F is Clos de Jacobins 1983 --------------------------------------------------- 8. ........ 8th place Wine B is Ch. Calons Segur 1983 We now test whether the ranksums AS A WHOLE provide a significant ordering. The Friedman Chi-square value is 8.7619. The probability that this could happen by chance is 0.2702 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 John Ken Burt John 1.000 -0.119 -0.167 Ken -0.119 1.000 -0.571 Burt -0.167 -0.571 1.000 Bob 0.143 -0.786 0.881 Orley 0.595 0.405 -0.571 Ed 0.310 0.524 -0.167 Dick 0.143 -0.619 0.143 Bob Orley Ed John 0.143 0.595 0.310 Ken -0.786 0.405 0.524 Burt 0.881 -0.571 -0.167 Bob 1.000 -0.333 -0.119 Orley -0.333 1.000 0.738 Ed -0.119 0.738 1.000 Dick 0.524 0.000 -0.071 Dick John 0.143 Ken -0.619 Burt 0.143 Bob 0.524 Orley 0.000 Ed -0.071 Dick 1.000 Pairwise correlations in descending order 0.881 Burt and Bob Significantly positive 0.738 Orley and Ed Significantly positive 0.595 John and Orley Not significant 0.524 Bob and Dick Not significant 0.524 Ken and Ed Not significant 0.405 Ken and Orley Not significant 0.310 John and Ed Not significant 0.143 John and Dick Not significant 0.143 Burt and Dick Not significant 0.143 John and Bob Not significant 0.000 Orley and Dick Not significant -0.071 Ed and Dick Not significant -0.119 Bob and Ed Not significant -0.119 John and Ken Not significant -0.167 Burt and Ed Not significant -0.167 John and Burt Not significant -0.333 Bob and Orley Not significant -0.571 Burt and Orley Not significant -0.571 Ken and Burt Not significant -0.619 Ken and Dick Not significant -0.786 Ken and Bob Significantly negative
COMMENT: The wines in this tasting represent a broad cross section of Bordeaux wines: one Graves, one St. Estephe, one St.Julien, one Pauillac, two Margaux and two St.Emilions. The overall grades received by the wines exhibit no patterns.
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