# Esplanade Club 2013 Payoff Matrices

by Matthew Kidd
April 14, 2014

I introduced the Payoff Matrix concept last October and showed results for six years of the La Jolla unit game based on the output generated by the Payoff Matrix software. Here I present similar results for the 2013 calendar year for the Esplanade Club in San Diego. As usual, the data shown in the visual matrices is limited to regular partnerships who play in enough sessions to generate decent statistics but full data is presented in the tab delimited text files which are available as a download at the end of this page.

The Esplanade Club runs several sessions per week, both open and limited games. The following table shows the average field strength for each session in order of decreasing strength. The 2013 La Jolla unit and San Diego unit open games are also included for comparison.

Field strength for each session
Session Mean (MP) Geomean (MP)
San Diego Unit open pairs 2874 1787
La Jolla Unit open pairs 2711 1567
Esplanade Tue Eve open pairs 1770 940
Esplanade Thu Eve Mentor/Mentee open pairs 1468 531
Esplanade Wed Aft open pairs 1021 496
Esplanade Fri Mor open pairs 769 384
Esplanade Tue Mor 499er pairs 77 39
Esplanade Thu Mor 499er pairs 60 29

Both the mean and geometric mean is shown. I have argued previously that the geometric mean is a better indicator of field strength than the mean. In a geometric mean, the mean is taken in a logarithmic manner. For example, the geometric mean of two players with 10 and 1000 MP respectively, is 100 MP not 505 MP. Less experienced players drag down the geometric mean more than the arithmetic mean. A field with a high geometric mean should in principle be uniformly fairly tough and offer few gifts.

The Esplanade payoff matrices are presented below in the order of decreasing field strength according to the table above.

Timothy Flaherty and John Houde dominated the Tuesday evening game in 2013 with a 59.52% average, beating the runner up partnership of Timothy Flaherty and Rick Norton Jr. by a full 4.8%. This is a stunning difference considering that John Houde and Rick Norton Jr. have a similar number of masterpoints (2600 vs. 3000 at the end of 2013). The partnership of Timothy Flaherty and Rick Norton Jr at 54.70% barely edges out Spencer Emtage and Michele Zuniga (54.55%), Leon Fisher and Fred Flam (54.5%), Larry Erickson and Paul Foster (54.35%), and Rex and Sheila Latux (54.25%). These 54-something percent partnerships are close enough that we can only assert with 60% confidence that the partnership of Timothy Flaherty and Rick Norton Jr. is better than the partnership of Rex and Sheila Latux given the entire year of data for Tuesday evening.

There is a lot of payoff matrix data, an entry for every partnership-partnership interaction, easily several thousand interactions over the course of a year. But many of the interactions only involve a few boards. The payoff matrix can be simplified by limiting it to the interactions between regular partnerships. However, this reduction still leaves us with several hundred interactions. It helps to see the reduced results visually, as shown below.

Both axes list the partnerships in order of decreasing strength for partnerships who played at least 10 sessions in 2013. Each square shows how well the partnership listed on corresponding row does against the partnership in the corresponding column. The color scale runs from solid blue (30% or lower) to solid yellow (70% or better) with grey at 50%. White squares indicate partnerships that have never played any boards against each other. Pink squares indicate partnerships that can not interact because they have one or more players in common. The diagonal is always pink.

Move the mouse over the image to view the details for each square (matrix element). The hovering tooltip will show the names of the two partnerships, each partnership’s average against the field, the number of boards the partnerships have played against each other, and in bold the average results of those boards including an error. The average result shows how well the partnership on the row did against the partnership on the column. The matrix is anti-symmetric about the diagonal. Squares with a faint red X denote statistics based on relatively few boards, fewer than 10 in this case.

The upper right corner of the matrix is mostly yellow. This is because stronger partnerships usually have an advantage against weaker partnerships. Conversely the lower left corner is mostly blue. However, there are interesting exceptions. For example, Ginger Calvert and Cheryl Rodzach cross up Christine Denny and William Bidermann.

### Over/Underperformance

Even a weak partnership might cause another partnership a lot of trouble by doing far better against that partnership than the difference in skill against the field would suggest should be the case. We could say that the weak partnership is overperforming against the stronger partnership.

The matrix below corrects for the difference in partnership skill, showing how much each partnership overperforms or underperforms against another partnership. The blue to yellow scale runs from -20% to 20% with grey at 0%. Move the mouse of the image to view the details for each square (matrix element). As before the partnership names and average percentage are shown. The over-perform / under-perform percentage is shown in bold. The ordinary percentage from the previous figure is also shown. Note: the previous figure also shows the over/under-performance statistics after ‘OU:’ as in ‘OU: 9.7%’.

The more yellowish and bluish square in the second matrix above are interesting because they indicate a pair that is strongly over/underperforming against another pair. The following table lists these relations in descending degree of payoff (or “exploitability”) where the pair-pair percentage is derived from at least 16 boards. Cnt is the number of boards that each interaction percentage based on.

Biggest Over/underperforming partnership interactions in the payoff matrix
Overperforming Pair Underperforming Pair Cnt OU%
Sheila Latus - Rex Latus Ginger Calvert - Cheryl Rodzach 23 14.18
Michele Zuniga - J Spencer Emtage Leon Fisher - Fred Flam 16 12.73
Janice Joerger - Marilyn Kalabsa Sheila Latus - Rex Latus 24 11.97
Lawrence Hauser - Barbara Hauser Ginger Calvert - Cheryl Rodzach 22 11.78
Rashad A Ansari - Jeffrey Leach Jeanette Bentley - Chuck Siggins 18 11.61
Richard Thome - Arthur Ostroff M Ali Mahdavi - Nicholas Krall 36 11.27
M Ali Mahdavi - Nicholas Krall Mary Woo - Roberta Massey 32 11.13
Suzanne Anson - Kay Childs Rick Norton Jr - Timothy Flaherty 16 10.78
Ginger Calvert - Cheryl Rodzach Richard Thome - Arthur Ostroff 21 10.53
Mary Woo - Roberta Massey Lawrence Hauser - Barbara Hauser 17 10.10
Vic Dhooge - Diana Glimm Barbara Naschold - Donald Cooper 56 9.99
Leon Fisher - Fred Flam Mary Woo - Roberta Massey 16 9.81
Rashad A Ansari - Jeffrey Leach M Ali Mahdavi - Nicholas Krall 18 9.57
Richard Thome - Arthur Ostroff Vic Dhooge - Diana Glimm 29 9.17
Lynn Wells - Janice Wells Rick Norton Jr - Timothy Flaherty 17 8.89
Joe Houde - Timothy Flaherty M Ali Mahdavi - Nicholas Krall 19 8.86
Suzanne Anson - Kay Childs M Ali Mahdavi - Nicholas Krall 32 8.45
Richard Thome - Arthur Ostroff Leon Fisher - Fred Flam 19 8.38
Emily Berkov - Barry Berkov W John Devine - Jan Gallagher 20 8.33
Harriet Smith - Judy Litman Emily Berkov - Barry Berkov 31 8.30
Mary Woo - Roberta Massey Lynn Wells - Janice Wells 31 8.29
Lynn Wells - Janice Wells Rashad A Ansari - Jeffrey Leach 23 8.23
Barbara Naschold - Donald Cooper Lynn Wells - Janice Wells 48 8.00
Lawrence Hauser - Barbara Hauser Michele Zuniga - J Spencer Emtage 22 7.95
M Ali Mahdavi - Nicholas Krall Christine Denny - William Bidermann 20 7.81
Paul Foster - Lawrence Erickson Harriet Smith - Judy Litman 60 7.71
Emily Berkov - Barry Berkov Barbara Naschold - Donald Cooper 35 7.69
Michele Zuniga - J Spencer Emtage Jeanette Bentley - Chuck Siggins 25 7.32
Christine Denny - William Bidermann Vic Dhooge - Diana Glimm 30 6.83
Lynn Wells - Janice Wells Christine Denny - William Bidermann 29 6.59
Jeanette Bentley - Chuck Siggins Emily Berkov - Barry Berkov 16 6.51
Paul Foster - Lawrence Erickson M Ali Mahdavi - Nicholas Krall 28 6.25
Harriet Smith - Judy Litman Ginger Calvert - Cheryl Rodzach 38 6.18
Lynn Wells - Janice Wells M Ali Mahdavi - Nicholas Krall 21 5.95
Harriet Smith - Judy Litman Christine Denny - William Bidermann 46 5.93
Dan Dayani - Bette Cornelius Mary Woo - Roberta Massey 16 5.88
Michele Zuniga - J Spencer Emtage Sheila Latus - Rex Latus 69 5.79
Harriet Smith - Judy Litman M Ali Mahdavi - Nicholas Krall 27 5.78
Ralph Dilley - John Kroener Michele Zuniga - J Spencer Emtage 18 5.66
Suzanne Anson - Kay Childs Paul Foster - Lawrence Erickson 54 5.57
Christine Denny - William Bidermann W John Devine - Jan Gallagher 39 5.48
Paul Foster - Lawrence Erickson Ralph Dilley - John Kroener 27 5.42
Emily Berkov - Barry Berkov Vic Dhooge - Diana Glimm 16 5.33
W John Devine - Jan Gallagher Dan Dayani - Bette Cornelius 17 5.32
Janice Joerger - Marilyn Kalabsa Lynn Wells - Janice Wells 20 5.23
Rick Norton Jr - Timothy Flaherty Sheila Latus - Rex Latus 20 5.16
M Ali Mahdavi - Nicholas Krall Janice Joerger - Marilyn Kalabsa 19 5.05

The table gives us much to speculate about and yet it is still a lot to absorb. Part of the difficulty is that many pairs are listed multiple times. A graph may be a better representation. Here is an example: OU ≥ 6%, where the graph represents the data in the table above down to advantages as small as 6%.

Unlike the Social Network graphs, the payoff graphs are directed, i.e they represent flow, the transport of over/underperformance around the partnership network. An incoming arrow represents a payoff to a partnership; an outgoing arrow represents payoff from a partnership.

It should be noted that although these are directed graphs, they are not directed acyclic graphs (DAGs), an important and well studied class of graphs. Cycles are easy to spot. For example Lynn and Janice Wells payoff to Mary Woo and Roberta Massey who payoff to M Ali Mahdavi and Nicholas Krall who payoff to Rashad Ansari Jeffrey Leach who complete the cycle by paying off to Lynn Wells Janice Wells. So turns the wheel of exploitation.

Scientists and mathematicians may be concerned about the fact that inflow and outflow are not equal at each node (pair) given that the over/underperformance numbers have compensated for the difference in partnership ability. There are two reasons for this. First, only the most prominent and statistically confident payoffs are shown. Many smaller payoffs are suppressed in order to avoid total clutter. Second, the payoff calculations are based on different numbers of boards. For example, an underperformance of 3% over 40 boards would be balanced by a overperformance of 6% over 20 boards.

## Esplanade Thursday evening mentor/mentee pairs

This session has a fairly high mean field strength but a comparably low geometric mean field strength because half the players are mentees.

The straight up and over/underperformance matrices below list the partnerships in order of decreasing strength for partnerships who played at least 7 sessions in 2013. Nicholas and Diane Krall (55.96% from 7 games) barely edge out Spencer Emtage and Afick Sharar (55.57% from 15 games), with Paul Foster and Sandy Kucha (55.28% from 15 games) in third place. These are close results. Statistically we can only say with 58% confidence that the Kralls are better than Spence and Afick in this game. Best Thursday evening game of the year goes to Lance and Anne Malkind, one time visitors who walked away with a 71.5% game.

Here is the Over/underperformance table where the pair-pair percentage is derived from at least 16 boards and OU ≥ 4 is shown. Cnt is the number of boards that each interaction percentage based on. Or view the graph.

Biggest Over/underperforming partnership interactions in the payoff matrix
Overperforming Pair Underperforming Pair Cnt OU%
Richard Thome - Lawrence Erickson Ralph Dilley - John Kroener 19 17.76
Barbara Naschold - Pat Matsumoto Harriet Smith - Judy Litman 19 13.22
Sandy Silverman - Vicki Shepperd Chin Ralph Dilley - John Kroener 20 12.76
Lynn Chambers - Tom Chambers Ralph Dilley - John Kroener 19 12.57
Lynn Chambers - Tom Chambers Sandy Silverman - Vicki Shepperd Chin 17 9.39
Sandy Silverman - Vicki Shepperd Chin Janice Joerger - Marilyn Kalabsa 22 9.12
Paul Foster - Sandy Kucha Diane Krall - Nicholas Krall 16 8.86
Diane Krall - Nicholas Krall Richard Thome - Lawrence Erickson 20 8.66
Paul Foster - Sandy Kucha Richard Thome - Lawrence Erickson 27 7.73
Richard Thome - Lawrence Erickson Janice Joerger - Marilyn Kalabsa 34 7.03
J Spencer Emtage - Afick Sharar W John Devine - Jan Gallagher 26 6.93
J Spencer Emtage - Afick Sharar Donna Wood - David Goldfarb 16 6.79
Richard Thome - Lawrence Erickson Donna Wood - David Goldfarb 16 6.17
Janice Joerger - Marilyn Kalabsa Lynn Chambers - Tom Chambers 16 5.84
Richard Thome - Lawrence Erickson Barbara Naschold - Pat Matsumoto 17 5.72
Paul Foster - Sandy Kucha Ralph Dilley - John Kroener 16 5.06
Harriet Smith - Judy Litman Lynn Chambers - Tom Chambers 27 4.36
Janice Joerger - Marilyn Kalabsa Harriet Smith - Judy Litman 26 4.18
Lynn Chambers - Tom Chambers Richard Thome - Lawrence Erickson 40 4.15
Sandy Silverman - Vicki Shepperd Chin Joan Kroener - Jeanette Bentley 20 4.05

## Esplanade Wednesday afternoon open pairs

The matrices are limited to pairs who have played at least 10 sessions. John and Rima Sharron lead the Wednesday afternoon game with a 58.09% average over 24 games. But they are closely followed by Larry Sherman and John Sack (57.63% over 18 games), a pair seasoned for several years by the often tough Soledad Thursday night game. Statistics only allows us to assert with 67% confidence that the Sharrons are the better pair. In third place, significantly behind is the partnership of Jan Gallagher and the late John Devine (55.85% over 24 games), allowing us to assert with 82% confidence that Larry and John are the better partnership.

Here is the Over/underperformance table where the pair-pair percentage is derived from at least 20 boards and OU ≥ 4 is shown. Cnt is the number of boards that each interaction percentage based on. Or view the graph.

Biggest Over/underperforming partnership interactions in the payoff matrix
Overperforming Pair Underperforming Pair Cnt OU%
Jeanette Bentley - Chuck Siggins Marvin Bauch - Robert Mann 29 13.58
Marvin Bauch - Robert Mann David Hawkins - Sharon Gabriel 22 13.13
Sharon Kambestad - Marcia Trombold Lawrence Sherman - John Sack 21 12.73
Rima Sharron - John Sharron Jr Kevin Chaisson - Meena Sethi 38 11.53
Eric Juline - Peter Clark Barbara Klein - Yael Aires 20 11.19
Wootsie Stockton - Jamie Detweiler Kevin Chaisson - Meena Sethi 37 10.63
Florence Cohen - Judy Dveris W John Devine - Jan Gallagher 32 10.47
Terry Paul - Chrissy Fried Hanan Deeby - Alice Lane 22 10.28
Kevin Chaisson - Meena Sethi Mary Lou Kammerer - Barbara Scherman 21 10.02
Harriet Smith - Edie Block Wootsie Stockton - Jamie Detweiler 24 9.28
Harriet Smith - Edie Block Eric Juline - Peter Clark 26 9.10
David Hawkins - Sharon Gabriel Florence Cohen - Judy Dveris 28 8.97
Paul Foster - Sandy Kucha Barbara Coffey - Charles Coffey 26 8.21
Barbara Klein - Yael Aires Terry Paul - Chrissy Fried 21 7.76
Patricia Newman - Carol Abramowitz Mary Ballin - Abe Gleiberman 28 7.72
Terry Paul - Chrissy Fried Mary Ballin - Abe Gleiberman 37 7.57
Barbara Klein - Yael Aires Richard Thome - Bob Schork 21 7.29
Kevin Chaisson - Meena Sethi Patricia Newman - Carol Abramowitz 33 7.17
Lawrence Sherman - John Sack Jeanette Bentley - Chuck Siggins 22 7.14
Mary Ballin - Abe Gleiberman Vicki Shepperd Chin - Mary Fenton 23 7.10
Vicki Shepperd Chin - Mary Fenton Kevin Chaisson - Meena Sethi 21 6.54
Eric Juline - Peter Clark Barbara Coffey - Charles Coffey 47 6.45
Paul Foster - Sandy Kucha Mary Ballin - Abe Gleiberman 23 6.42
Hanan Deeby - Alice Lane Florence Cohen - Judy Dveris 24 6.19
Mary Ballin - Abe Gleiberman Rima Sharron - John Sharron Jr 27 5.88
Terry Paul - Chrissy Fried Rose Zakarian - Emily Berkov 27 5.84
Wootsie Stockton - Jamie Detweiler Barbara Klein - Yael Aires 30 5.76
Eric Juline - Peter Clark Sharon Kambestad - Marcia Trombold 25 5.46
Terry Paul - Chrissy Fried Sharon Kambestad - Marcia Trombold 25 5.44
Kevin Chaisson - Meena Sethi Terry Paul - Chrissy Fried 34 5.30
Marvin Bauch - Robert Mann W John Devine - Jan Gallagher 36 5.03
Rose Zakarian - Emily Berkov Rima Sharron - John Sharron Jr 40 4.91
Kevin Chaisson - Meena Sethi Richard Thome - Bob Schork 21 4.85
David Hawkins - Sharon Gabriel Rima Sharron - John Sharron Jr 20 4.65
Barbara Coffey - Charles Coffey Raghubir Mathur - Ruth Aronsohn 24 4.61
W John Devine - Jan Gallagher Rima Sharron - John Sharron Jr 28 4.09
Rima Sharron - John Sharron Jr Sharon Kambestad - Marcia Trombold 27 4.01

## Esplanade Friday morning open pairs

As with the Wednesday afternoon open game, the matrices are limited to pairs who have played at least 10 sessions. The partnerships of Joe Houde and Ron Kay (61.05% over 11 games), and Kevin Chaisson and Philippe Lamoise (58.28% over 16 games) are a clear first and second place, ahead of a pack of partnerships averaging 55.81 and below. We can be more than 90% certain both that the first place partnership is better than second place partnerships and that the second place partnership is better than the third place partnership.

Here is the Over/underperformance table where the pair-pair percentage is derived from at least 20 boards and OU ≥ 4 is shown. Cnt is the number of boards that each interaction percentage based on. Or view the graph.

Biggest Over/underperforming partnership interactions in the payoff matrix
Overperforming Pair Underperforming Pair Cnt OU%
Mary Ballin - Abe Gleiberman Christine Denny - J Spencer Emtage 20 12.90
Christine Denny - J Spencer Emtage Barbara Farfel - Martin Farfel 20 12.52
Donald Cleveland - Harvey Schleifstein Mary Ballin - Abe Gleiberman 21 12.47
Michele Zuniga - Roberta Massey Chris Kelly - Isabella Pommier 23 12.10
Mary Lou Kammerer - Patricia Prahm Joyce Pickersgill - Vivian Entous 25 11.04
Donald Cleveland - Harvey Schleifstein Joyce Pickersgill - Vivian Entous 25 10.28
Jeanette Bentley - Chuck Siggins Vic Dhooge - Mike O'Leary 20 9.05
Marilyn Kalabsa - Ruth Aronsohn Kevin Chaisson - Philippe Lamoise 20 8.51
Joyce Pickersgill - Vivian Entous Paul Foster - Judd Halenza 23 8.18
Leah Stark - Edgar Wessel Joyce Pickersgill - Vivian Entous 30 7.93
Joyce Pickersgill - Vivian Entous Michele Zuniga - Roberta Massey 38 7.04
Kevin Chaisson - Philippe Lamoise Vic Dhooge - Mike O'Leary 22 6.31
Barbara Farfel - Martin Farfel Michele Zuniga - Roberta Massey 30 6.01
Kevin Chaisson - Philippe Lamoise Donald Cleveland - Harvey Schleifstein 20 5.83
Leah Stark - Edgar Wessel Lawrence Hauser - Barbara Hauser 23 5.70
Jeanette Bentley - Chuck Siggins Leah Stark - Edgar Wessel 20 5.68
Lawrence Hauser - Barbara Hauser Paul Foster - Judd Halenza 20 5.37
Mary Lou Kammerer - Sandra Musbach Barbara Farfel - Martin Farfel 20 5.21
Michele Zuniga - Roberta Massey Mary Ballin - Abe Gleiberman 30 5.19
Marilyn Kalabsa - Ruth Aronsohn Jane Petering - Paula Alexander 23 4.54
Joyce Pickersgill - Vivian Entous Christine Denny - J Spencer Emtage 26 4.24
Joyce Pickersgill - Vivian Entous Marilyn Kalabsa - Ruth Aronsohn 39 4.17

## Esplanade Tuesday and Thursday morning 499er pairs

There is considerable overlap between the pairs in both morning 499er games. Therefore, it makes sense to create a single set of payoff matrices from the combined dataset.

The matrices are limited to pairs who have played at least 10 sessions between the two 499er sessions. It’s a close race at the top around 55% led by Alan and Lorna Strang (55.45% over 60 games), Wallace Mccoy and Leroy Wisper (55.34 over 17 games), and Vivian Entous and Ray Miller (54.83% over 26 games).

Here is the Over/underperformance table where the pair-pair percentage is derived from at least 20 boards and OU ≥ 5 is shown. Cnt is the number of boards that each interaction percentage based on. Or view the graph.

Biggest Over/underperforming partnership interactions in the payoff matrix
Overperforming Pair Underperforming Pair Cnt OU%
Wallace Mccoy - Leroy Wisper Thomas Boardman - John Trombold 21 15.20
Joyce Pickersgill - Darlene Bigos Lori Eichenfield - Fran Subar 21 15.00
Batia Kvashny - Isabella Wilf Mary Anne Curray - Dolores Boily 29 13.60
Thomas Boardman - John Trombold Greg Smith - Kay Earley 25 13.54
Thomas Boardman - John Trombold Nat Cordova - Geri Cordova 38 12.65
Greg Smith - Kay Earley Vivian Entous - Ray Miller 23 11.65
Bernard Goott - Joan Goott Vivian Entous - Ray Miller 21 11.17
Thomas Boardman - John Trombold Judee Feinberg - Claire Altman 40 10.36
Alan Strang - Lorna Strang Janie Killermann - Sheri Meek 26 9.97
Alan Strang - Lorna Strang Sharon Mack - Irene Cooper 45 9.47
Vivian Entous - Ray Miller Nancy Shelmon - Maureen Sage 24 9.05
Lori Eichenfield - Fran Subar Thomas Boardman - John Trombold 23 8.48
Simma Nemeth - Joyce Pickersgill Batia Kvashny - Isabella Wilf 27 8.03
Nat Cordova - Geri Cordova Joyce Durra - Cheryl Griffiths 21 7.76
Vivian Entous - Ray Miller Joyce Pickersgill - Darlene Bigos 24 7.67
Sharon Mack - Irene Cooper Mary Anne Curray - Dolores Boily 21 7.19
Wallace Mccoy - Leroy Wisper Alan Strang - Lorna Strang 27 6.97
Thomas Boardman - John Trombold Vivian Entous - Ray Miller 20 6.75
Nancy Shelmon - Maureen Sage Greg Smith - Kay Earley 44 6.70
Mary Anne Curray - Dolores Boily Alan Strang - Lorna Strang 34 6.56
Don Glickman - Maureen Culhane Rosemary Love - Sheri Meek 20 6.19
Alan Strang - Lorna Strang Nancy Shelmon - Maureen Sage 22 6.05
Vivian Entous - Ray Miller Judee Feinberg - Claire Altman 27 5.93
Bernard Goott - Joan Goott Rosemary Love - Sheri Meek 23 5.81
Bernard Goott - Joan Goott Nancy Shelmon - Maureen Sage 32 5.80
John Oden - Miki Oden Joyce Pickersgill - Darlene Bigos 20 5.71
Alan Strang - Lorna Strang Rosemary Love - Sheri Meek 50 5.46
Mary Anne Curray - Dolores Boily Janie Killermann - Sheri Meek 28 5.42
Thomas Boardman - John Trombold John Oden - Miki Oden 24 5.18
Janie Killermann - Sheri Meek Wallace Mccoy - Leroy Wisper 21 5.18
Vivian Entous - Ray Miller Alan Strang - Lorna Strang 24 5.09
Nancy Shelmon - Maureen Sage Nat Cordova - Geri Cordova 43 4.85

## Get the data

Download a zip file (1 MB) of all the tab delimited text files created by the Payoff Matrix software and used to generate the payoff matrix images above. For convenience, an Excel version of some files is also included. A filename such as Esp-2013-Wed-Aft-min-10-payoff-matrix.txt means the 2013 Esplanade Club payoff matrix data for the Wednesday afternoon session after restricting to partnerships that have played at least 10 sessions. If min-# is not included in the filename, no minimum session cut has been applied. The definition of each column is explained in the Payoff Matrix software documentation. The zip file also includes the images and the image specific JavaScript files.