WINETASTER ON 06/02/08 WITH 7 JUDGES AND 8 WINES BASED ON RANKS, IDENT=Y Copyright (c) 1995-2008 Richard E. Quandt, V. 1.65

Today's tasting comprises two flights of relatively inexpensive 2005 Bordeaux wines. The same judges participated in both flights.

FLIGHT 1: Number of Judges = 7 Number of Wines = 8

Identification of the Wine: The judges' overall ranking:

Wine A is Ch. La Rose Mayat, Puissegon St.Emilion ........ 6th place Wine B is Ch. Bellisle Mondotte, St. Emilion ........ 1st place Wine C is Ch. de Lavagnac, St. Emilion ........ 2nd place Wine D is Ch. Quercy, St. Emilion Grand Cru tied for 4th place Wine E is Ch. Lauriol, Côtes de Francs ........ 7th place Wine F is La Sacristie de Vielle Cure, Fronsac ........ 3rd place Wine G is Ch. La Bourrée, Côtes de Castillon tied for 4th place Wine H is Ch. St. Sulpice, Entre Deux Mers ........ 8th place

The Judges's Rankings

Judge Wine -> A B C D E F G H Bob 3. 1. 2. 4. 6. 5. 7. 8. Mike 3. 6. 7. 5. 8. 1. 2. 4. Lou 3. 5. 8. 6. 2. 1. 4. 7. Ted 8. 1. 2. 6. 4. 7. 3. 5. John 6. 4. 1. 3. 8. 2. 5. 7. Ed 6. 5. 1. 2. 4. 7. 8. 3. Dick 8. 1. 3. 5. 6. 4. 2. 7.

Table of Votes Against Wine -> A B C D E F G H

Group Ranking -> 6 1 2 4 7 3 4 8 Votes Against -> 37 23 24 31 38 27 31 41

( 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 = 0.1516

The probability that random chance could be responsible for this correlation is rather large, 0.3857. 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.

The correlation I measures the degree to which the identification of each judge is correlated with the truth. Here a 1.0 means that the judge identified the wines perfectly, and a 0 means that he identified none of them.

Correlation Between the Ranks of Each Person With the Average Ranking of Others

Name of Person Correlation R Correlation Price John 0.7381 -0.4880 Dick 0.6707 0.3172 Bob 0.4392 0.3904 Ted 0.1796 -0.2684 Mike -0.2530 -0.4392 Ed -0.3234 -0.5123 Lou -0.5030 -0.3172

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 Ch. Bellisle Mondotte, St. Emilion 2. ........ 2nd place Wine C is Ch. de Lavagnac, St. Emilion 3. ........ 3rd place Wine F is La Sacristie de Vielle Cure, Fronsac 4. tied for 4th place Wine G is Ch. La Bourrée, Côtes de Castillon 5. tied for 4th place Wine D is Ch. Quercy, St. Emilion Grand Cru 6. ........ 6th place Wine A is Ch. La Rose Mayat, Puissegon St.Emilion 7. ........ 7th place Wine E is Ch. Lauriol, Côtes de Francs 8. ........ 8th place Wine H is Ch. St. Sulpice We now test whether the ranksums AS A WHOLE provide a significant ordering. The Friedman Chi-square value is 7.4286. The probability that this could happen by chance is 0.3857

We now test whether the group ranking of wines is correlated with the prices of the wines. The rank correlation between them is -0.4909. 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 Bob Mike Lou Bob 1.000 -0.333 -0.167 Mike -0.333 1.000 0.381 Lou -0.167 0.381 1.000 Ted 0.262 -0.548 -0.452 John 0.548 0.143 -0.262 Ed 0.238 -0.714 -0.738 Dick 0.357 -0.048 -0.143 Ted John Ed Bob 0.262 0.548 0.238 Mike -0.548 0.143 -0.714 Lou -0.452 -0.262 -0.738 Ted 1.000 0.143 0.214 John 0.143 1.000 0.190 Ed 0.214 0.190 1.000 Dick 0.762 0.548 -0.167 Dick Bob 0.357 Mike -0.048 Lou -0.143 Ted 0.762 John 0.548 Ed -0.167 Dick 1.000 Pairwise correlations in descending order 0.762 Ted and Dick Significantly positive 0.548 Bob and John Not significant 0.548 John and Dick Not significant 0.381 Mike and Lou Not significant 0.357 Bob and Dick Not significant 0.262 Bob and Ted Not significant 0.238 Bob and Ed Not significant 0.214 Ted and Ed Not significant 0.190 John and Ed Not significant 0.143 Ted and John Not significant 0.143 Mike and John Not significant -0.048 Mike and Dick Not significant -0.143 Lou and Dick Not significant -0.167 Bob and Lou Not significant -0.167 Ed and Dick Not significant -0.262 Lou and John Not significant -0.333 Bob and Mike Not significant -0.452 Lou and Ted Not significant -0.548 Mike and Ted Not significant -0.714 Mike and Ed Significantly negative -0.738 Lou and Ed Significantly negative

COMMENT: This is the first of two flights of tastings from 2005 Bordeaux wines. They all tasted remarkably good and drinkable. They all had very soft tannins and the top four wines were really quite outstanding. At least two of the top four wines in this tasting had a high Merlot content which may account for their relatively high rankings. The ripeness of the fruit in these wines is also quite evident. But overall, the wines were quite comparable, which is revealed by the facts that the overall correlation in the group was quite low and that none of the wines was significantly preferred over the others.

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WINETASTER ON 06/02/08 WITH 7 JUDGES AND 8 WINES BASED ON RANKS, IDENT=N Copyright (c) 1995-2008 Richard E. Quandt, V. 1.65

FLIGHT 2: Number of Judges = 7 Number of Wines = 8

Identification of the Wine: The judges' overall ranking:

Wine A is Ch. Recougne, Terra Incognita ........ 8th place Wine B is Ch. Pey La Tour, Bordeaux Supérieur ........ 7th place Wine C is Grands Chenes, St. Christoly Médoc ........ 6th place Wine D is Ch. Marjosse, Grand vin Bordeaux tied for 3rd place Wine E is Ch. Puy Bardens, Côtes de Bordeaux ........ 1st place Wine F is Ch. le Pavillon de Boyrein, Graves tied for 3rd place Wine G is Ch. Barreyre, Bordeaux Supérieur ........ 2nd place Wine H is Ch. La Grange Clinet, Côtes de Bordeaux ........ 5th place

The Judges's Rankings

Judge Wine -> A B C D E F G H Bob 3. 4. 5. 6. 8. 7. 2. 1. Mike 5. 6. 8. 3. 4. 2. 1. 7. Lou 4. 5. 6. 8. 7. 3. 1. 2. Ted 7. 8. 1. 3. 2. 6. 5. 4. John 8. 7. 6. 2. 1. 3. 5. 4. Ed 7. 6. 1. 4. 2. 3. 8. 5. Dick 4. 1. 8. 3. 2. 5. 6. 7.

Table of Votes Against Wine -> A B C D E F G H

Group Ranking -> 8 7 6 3 1 3 2 5 Votes Against -> 38 37 35 29 26 29 28 30

( 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 = 0.0690

The probability that random chance could be responsible for this correlation is rather large, 0.8477. 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 John 0.6747 -0.2036 Mike 0.0488 0.2036 Ted -0.0723 -0.2275 Ed -0.2651 -0.1916 Lou -0.3095 0.8503 Dick -0.4431 -0.6826 Bob -0.6429 0.3832

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 E is Ch. Puy Bardens, Côtes de Bordeaux 2. ........ 2nd place Wine G is Ch. Barreyre, Bordeaux Supérieur 3. tied for 3rd place Wine F is Ch. le Pavillon de Boyrein, Graves 4. tied for 3rd place Wine D is Ch. Marjosse, Grand vin Bordeaux 5. ........ 5th place Wine H is Ch. La Grange Clinet, Côtes de Bordeaux 6. ........ 6th place Wine C is Grands Chènes, St. Christoly Médoc 7. ........ 7th place Wine B is Ch. Pey La Tour, Bordeaux Supérieur 8. ........ 8th place Wine A is Ch. Recougne, Terra Incognita We now test whether the ranksums AS A WHOLE provide a significant ordering. The Friedman Chi-square value is 3.3810. The probability that this could happen by chance is 0.8477

We now test whether the group ranking of wines is correlated with the prices of the wines. The rank correlation between them is 0.0060. 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 Bob Mike Lou Bob 1.000 -0.238 0.690 Mike -0.238 1.000 0.214 Lou 0.690 0.214 1.000 Ted -0.333 -0.214 -0.452 John -0.595 0.405 -0.333 Ed -0.714 -0.333 -0.595 Dick -0.429 0.238 -0.476 Ted John Ed Bob -0.333 -0.595 -0.714 Mike -0.214 0.405 -0.333 Lou -0.452 -0.333 -0.595 Ted 1.000 0.548 0.714 John 0.548 1.000 0.500 Ed 0.714 0.500 1.000 Dick -0.405 0.143 -0.143 Dick Bob -0.429 Mike 0.238 Lou -0.476 Ted -0.405 John 0.143 Ed -0.143 Dick 1.000 Pairwise correlations in descending order 0.714 Ted and Ed Significantly positive 0.690 Bob and Lou Significantly positive 0.548 Ted and John Not significant 0.500 John and Ed Not significant 0.405 Mike and John Not significant 0.238 Mike and Dick Not significant 0.214 Mike and Lou Not significant 0.143 John and Dick Not significant -0.143 Ed and Dick Not significant -0.214 Mike and Ted Not significant -0.238 Bob and Mike Not significant -0.333 Bob and Ted Not significant -0.333 Lou and John Not significant -0.333 Mike and Ed Not significant -0.405 Ted and Dick Not significant -0.429 Bob and Dick Not significant -0.452 Lou and Ted Not significant -0.476 Lou and Dick Not significant -0.595 Bob and John Not significant -0.595 Lou and Ed Not significant -0.714 Bob and Ed Significantly negative

COMMENT: This second flight of wines was not quite as impressive as the first flight. However, one taster thought the exact opposite. This taster thought that the second flight had more grape variety and that in this flight there was more cabernet. In any event, the wines were very enjoyable. We note that the rank sums in this group were even more tightly bunched than in Flight 1 (which does not necessarily reflect the quality of the wines, but possibly the increasing randomness in the tasters' choices resulting from the consumption of a second set of eight bottles). It is important to note that the 2005 Bordeaux are ready to drink now and are extremely enjoyable. Because of their prices, these wines are tremendous values. Buy them now.

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