WINETASTER ON 02/06/12 WITH 8 JUDGES AND 8 WINES BASED ON RANKS, IDENT=N Copyright (c) 1995-2012 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 Groth Oakville 2000 ........ 5th place Wine B is Opus One 1998 ........ 1st place Wine C is BV Geroges de Latour 2001 ........ 4th place Wine D is Penfolds Bin 389 1996 ........ 7th place Wine E is Silver Oak Napa 2000 tied for 2nd place Wine F is Overture (Opus) NV tied for 2nd place Wine G is Igneous 2004 ........ 8th place Wine H is Chateau Montelena 1999 ........ 6th place
The Judges's Rankings
Judge Wine -> A B C D E F G H Ed 5. 3. 1. 4. 8. 2. 6. 7. Alan 5. 1. 2. 4. 6. 3. 7. 8. Lori 3. 5. 4. 7. 1. 2. 6. 8. Burt 5. 1. 7. 4. 3. 6. 8. 2. Zaki 5. 3. 4. 7. 1. 6. 8. 2. Bob 6. 3. 7. 8. 1. 2. 5. 4. Orley 3. 1. 2. 6. 8. 5. 7. 4. Dick 8. 3. 7. 5. 2. 4. 1. 6.
Table of Votes Against Wine -> A B C D E F G H
Group Ranking -> 5 1 4 7 2 2 8 6 Votes Against -> 40 20 34 45 30 30 48 41
( 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 = 0.2225
The probability that random chance could be responsible for this correlation is quite small, 0.0865. 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 Lori 0.5000 Alan 0.4910 Zaki 0.4048 Orley 0.3473 Bob 0.3114 Burt 0.2635 Ed 0.1905 Dick -0.0714
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 B is Opus One 1998 --------------------------------------------------- 2. tied for 2nd place Wine E is Silver Oak Napa 2000 3. tied for 2nd place Wine F is Overture (Opus) NV 4. ........ 4th place Wine C is BV Geroges de Latour 2001 5. ........ 5th place Wine A is Groth Oakville 2000 6. ........ 6th place Wine H is Chateau Montelena 1999 7. ........ 7th place Wine D is Penfolds Bin 389 1996 --------------------------------------------------- 8. ........ 8th place Wine G is Igneous 2004 We now test whether the ranksums AS A WHOLE provide a significant ordering. The Friedman Chi-square value is 12.4583. The probability that this could happen by chance is 0.0865 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 Alan Lori Ed 1.000 0.857 0.095 Alan 0.857 1.000 0.286 Lori 0.095 0.286 1.000 Burt -0.310 0.048 -0.167 Zaki -0.333 -0.048 0.238 Bob -0.333 -0.095 0.524 Orley 0.619 0.619 -0.143 Dick -0.333 -0.143 0.095 Burt Zaki Bob Ed -0.310 -0.333 -0.333 Alan 0.048 -0.048 -0.095 Lori -0.167 0.238 0.524 Burt 1.000 0.690 0.357 Zaki 0.690 1.000 0.524 Bob 0.357 0.524 1.000 Orley 0.238 0.190 -0.238 Dick 0.000 -0.095 0.548 Orley Dick Ed 0.619 -0.333 Alan 0.619 -0.143 Lori -0.143 0.095 Burt 0.238 0.000 Zaki 0.190 -0.095 Bob -0.238 0.548 Orley 1.000 -0.571 Dick -0.571 1.000 Pairwise correlations in descending order 0.857 Ed and Alan Significantly positive 0.690 Burt and Zaki Significantly positive 0.619 Ed and Orley Not significant 0.619 Alan and Orley Not significant 0.548 Bob and Dick Not significant 0.524 Lori and Bob Not significant 0.524 Zaki and Bob Not significant 0.357 Burt and Bob Not significant 0.286 Alan and Lori Not significant 0.238 Burt and Orley Not significant 0.238 Lori and Zaki Not significant 0.190 Zaki and Orley Not significant 0.095 Lori and Dick Not significant 0.095 Ed and Lori Not significant 0.048 Alan and Burt Not significant 0.000 Burt and Dick Not significant -0.048 Alan and Zaki Not significant -0.095 Alan and Bob Not significant -0.095 Zaki and Dick Not significant -0.143 Lori and Orley Not significant -0.143 Alan and Dick Not significant -0.167 Lori and Burt Not significant -0.238 Bob and Orley Not significant -0.310 Ed and Burt Not significant -0.333 Ed and Zaki Not significant -0.333 Ed and Bob Not significant -0.333 Ed and Dick Not significant -0.571 Orley and Dick Not significant
COMMENT: We had two guests present and one of them predicted the group preferences better than anyone today. These were wines that were distinguishable from one another, but it wasn´t always clear which to prefer. Only one person picked out the Australian wine. The reason for this success in picking out this wine was the overwhelming smell of cherries, taste like chalk and it hit the front of the tongue and not the back. One taster thought the Montelena was too smooth and boring. These were all typical Napa valley cabernets with lots of fruit, good drinking now and without anyone knowing whether any one of them will get better. The older wines are holding well. Overture is a second wine of Opus One, carries no vintage date, and many of us were puzzled by how well it performed. It was a wine unknown to everybody but our host. Note that this is not the first time that Opus One has won a tasting, having won against Bordeaux, etc.
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