WINETASTER ON 01/06/20 WITH 6 JUDGES AND 6 WINES BASED ON RANKS, IDENT=N Copyright (c) 1995-2020 Richard E. Quandt, V. 1.65
FLIGHT 1: Number of Judges = 6 Number of Wines = 6
Identification of the Wine: The judges' overall ranking:
Wine A is Ch. d'Ampuis Guigal 2001 tied for 3rd place Wine B is Hermitage La Sizeranne 1997 ........ 5th place Wine C is Cornas Dom. Clape 2001 ........ 2nd place Wine D is Cornas Dom. Clape 1997 ........ 1st place Wine E is Hermitage La Chappelle 2001 ........ 6th place Wine F is Ch.d'Ampuis Guigal 1997 tied for 3rd place
The Judges's Rankings
Judge Wine -> A B C D E F Stephen 6. 5. 2. 1. 3. 4. Burt 1. 5. 4. 2. 6. 3. Bob 3. 4. 2. 1. 6. 5. Zaki 5. 6. 4. 3. 1. 2. Thom 3. 4. 1. 2. 6. 5. Dick 2. 3. 5. 4. 6. 1.
Table of Votes Against Wine -> A B C D E F
Group Ranking -> 3 5 2 1 6 3 Votes Against -> 20 27 18 13 28 20
( 6 is the best possible, 36 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 = 0.2540
The probability that random chance could be responsible for this correlation is rather large, 0.1785. 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 Burt 0.5798 Bob 0.5429 Thom 0.3769 Stephen 0.2029 Dick -0.0857 Zaki -0.2000
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 Cornas Dom. Clape 1997 --------------------------------------------------- 2. ........ 2nd place Wine C is Cornas Dom. Clape 2001 3. tied for 3rd place Wine A is Ch. d'Ampuis Guigal 2001 4. tied for 3rd place Wine F is Ch.d'Ampuis Guigal 1997 5. ........ 5th place Wine B is Hermitage La Sizeranne 1997 --------------------------------------------------- 6. ........ 6th place Wine E is Hermitage La Chappelle 2001 We now test whether the ranksums AS A WHOLE provide a significant ordering. The Friedman Chi-square value is 7.6190. The probability that this could happen by chance is 0.1785 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 0.89 for significance at the 0.05 level and must exceed 0.83 for significance at the 0.1 level Stephen Burt Bob Stephen 1.000 -0.143 0.429 Burt -0.143 1.000 0.600 Bob 0.429 0.600 1.000 Zaki 0.486 -0.257 -0.429 Thom 0.371 0.486 0.943 Dick -0.600 0.600 -0.029 Zaki Thom Dick Stephen 0.486 0.371 -0.600 Burt -0.257 0.486 0.600 Bob -0.429 0.943 -0.029 Zaki 1.000 -0.486 -0.314 Thom -0.486 1.000 -0.086 Dick -0.314 -0.086 1.000 Pairwise correlations in descending order 0.943 Bob and Thom Significantly positive 0.600 Burt and Dick Not significant 0.600 Burt and Bob Not significant 0.486 Burt and Thom Not significant 0.486 Stephen and Zaki Not significant 0.429 Stephen and Bob Not significant 0.371 Stephen and Thom Not significant -0.029 Bob and Dick Not significant -0.086 Thom and Dick Not significant -0.143 Stephen and Burt Not significant -0.257 Burt and Zaki Not significant -0.314 Zaki and Dick Not significant -0.429 Bob and Zaki Not significant -0.486 Zaki and Thom Not significant -0.600 Stephen and Dick Not significant
COMMENT: Ther wines were basically very similar, which makes it interesting that with asw few as 6 tasters and 6 wines one turned out to be significantly liked and one significantly not liked. It was noticeable that the top two rated wines were from Cornas, which were the most expensive wines. These high Syrrah wines from first rate producers bear out the received wisdom that these wines justify long term cellaring. There appeared to be no significant difference between the two vintages.
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