Monday, December 26, 2011

Christmas Day was Opening Day in the NBA this season, thanks to the owners' lockout. Among the marquee match-ups was a Chicago Bulls visit to play the L.A. Lakers. For most of the second half, Chicago's shooting showed the rust of a longer-than-usual off-season. However, the Bulls caught fire in the closing minutes to pull out a stunning 88-87 victory.

Below is a shot-sequence chart for Chicago, based on the play-by-play sheet. I haven't done one of these in a long time, but it seemed fitting for the Bulls' second half. (You may click on the graphic to enlarge it.)


For roughly the first 20 of the 24 second-half minutes, Chicago's missed shots (blue) greatly outnumbered its made baskets (red). As shown in the legend at the bottom of the chart, longer line segments indicate greater distances of shot attempts. For the stretch highlighted in pale yellow, the Bulls missed 21 of 22 field-goal attempts. However, the Bulls came back to score 18 points in just the final 4:13 of the game, which was enough to win.

Sunday, December 18, 2011

Streak-buster Sunday in the NFL

Not only did the Denver Broncos' six-game winning streak -- powered by quarterback Tim Tebow's frantic rallying of the team -- come to an end today. So did two other major streaks in the National Football League.

Denver lost 41-23 to New England. Tebow worked as feverishly as ever to bring the Broncos back, but Denver's defense allowed the Patriots to score enough to maintain comfortable leads.

The Green Bay Packers, who entered today's play with a 13-0 record, lost to Kansas City, 19-14.

Finally, at the other end of the spectrum, the previously 0-13 Indianapolis Colts got their first win of the season, with a 27-13 victory over Tennessee.

Wednesday, December 14, 2011

American football fans are abuzz with what has been termed "Tebow-mania" or "Tebow Fever." The reference is to Denver Broncos' quarterback Tim Tebow, whose unorthodox playing style, his "mixing faith with football" (in the words of one writer), and his team's winning ways have garnered him great attention.

As seen in the Broncos' game-by-game log, Denver won in Tebow's first start, October 23 at Miami, lost the next week to Detroit, and then went on a still-ongoing six-game winning streak. Amanda Rykoff, writing in an ESPN-W "roundtable discussion" captures the essence of Tebow-mania:

...I'm not going to try to explain why he's 7-1 as a starter for the Broncos this year. Or why Denver has been able to come from behind late in the fourth quarter in five of those seven victories. Or how the Broncos managed to win what seemed to be an absolutely unwinnable game on Sunday against the Bears, trailing 10-0 with two minutes left in regulation.

The blog "This Given Sunday" has a detailed summary of each Broncos/Tebow win during the stretch.

The improbable nature of many Bronco wins has led probability analysts to estimate the likelihood of Denver's comeback-heavy winning streak. The key element is the win probability in each game, based on historical data. If you click here to get to the Advanced NFL Stats website and then scroll down to the graph with all the wavy lines, you'll get an idea of win probability. First, you would select one of the lines, corresponding to how your team is doing with regard to score (e.g., leading by 7, trailing by 3). Once you have your line, then follow it along the horizontal axis corresponding to how many minutes remained in the game. For example, a team trailing by 7 entering the fourth quarter tends to win about 10% of the time.

Using a chart like the one above, analysts would then find the win probabilities for Denver in each of its victories, given the depth of Denver's dire circumstances in a given game (i.e., when it trailed the most with the least time remaining). One can then multiply the probabilities together to get an overall probability estimate of the Broncos' streak. (This is analogous to calculating the probability of rolling double-sixes with a pair of dice by multiplying 1/6, which is the probability of a six on one die, by 1/6, the probability of a six on the other die, to yield 1/36.)

Using this methodology, ESPN's Statistics and Information Blog estimates a probability of Denver winning its last six straight at "approximately one in 137,000. The odds are better that a flipped coin comes up heads 17 consecutive times."

"This Given Sunday" (the blog cited above) calculates the probability of the Broncos winning the seven games with Tebow as starter (ignoring the one loss). The verdict: "the odds of the Broncos winning all seven games from their lowest odds in each particular game situation [are] 1 in 27 million."

If you're going to use seven as the win total, you must take into account the one loss, in my view. The seven game-specific probabilities from "This Given Sunday" are as follows:

.01, .15, .58, .17, .18, .14, .01

If you throw out the high and low values, the Tebow-led Broncos typically faced around a .15 probability of winning in many of the games during the stretch. Using an online tool known as a Binomial Probability Calculator, we can ask the question: For a team that faced only a .15 probability of winning each game, what is the likelihood of that team winning seven or more out of eight games? The answer, given these assumptions, is .00001 or 1-in-100,000.

As many writers have acknowledged, Tebow obviously should not get sole credit for Denver's winning stretch. However, his contribution appears to be great. One metric is quarterback efficiency ratings, which attempt to boil down many passing statistics (e.g., completion rate, yardage gained, touchdowns, interceptions) into a single number.

ESPN's Statistics and Information Blog notes that Tebow has the highest score (96.3) on one such metric, the Total QBR, of all NFL quarterbacks this season in the final 7 minutes of the fourth quarter (using a certain minute-mark rather than, say, the fourth quarter as a whole seems a little arbitrary; would Tebow still lead if we used the final 8 minutes or 6 minutes?).

Along with Denver's defense, which has had to shut down opposing offenses, another key figure in the Broncos' recent success is kicker Matt Prater. Without his hot foot, the winning streak would be over. According to Adena Andrews's commentary in the aforementioned ESPN-W roundtable:

Prater, who was recognized as the AFC special teams player of the week after his performance against the Bears on Sunday (a 59-yard field goal to tie the game, and then a 51-yarder for the overtime victory), has hit 28 of the 29 career field goals he has attempted in the fourth quarter or overtime.

One final factor to consider is that, as unusual as the Broncos' stretch appears, maybe in the larger historical scheme it is not so unexpected. The National Football League has been around for roughly 90 years. Initially, the league had around 10 teams, and increased over the years to the teens and mid-twenties (with the NFL-AFL merger), and continued to expand to the present 32 teams. The number of games per team per season has increased from roughly 10-12 in the early years to the present 16.

Let's say that, in a given season under the modern schedule, each team would have 10 opportunities to begin a winning stretch for six games (e.g., right from the start, beginning after Week 1, beginning after Week 2, etc.). Once Week 11 had gone by, of course, it would no longer be possible to start a six-game winning streak.

As a simplification, let's say further that within each of the most recent 30 seasons, there were 300 opportunities for a six-game winning streak (roughly 30 teams X 10 opportunities); that for each of the prior 30 years, there were 200 opportunities; and for the first 30 years of the NFL, there were 100 annual opportunities. That yields roughly 18,000 opportunities. Considering the above likelihood estimate of the Broncos'  winning six straight in the comeback fashion they did (i.e., 1-in-137,000), it seems that Denver's recent feat goes beyond the ordinary course of events.

Friday, December 09, 2011

Penn State's run of consecutive NCAA women's volleyball championships, which reached four last year, is now over. The Nittany Lions were eliminated this evening in three straight games by UCLA in the Sweet 16 round.

Thursday, December 08, 2011

Today, I did my first-ever book signing, in the bookstore of my home university, Texas Tech. Several people, mainly friends and colleagues, came by. Thanks to everyone who came by to chat and/or buy the book!

Monday, December 05, 2011

Tiger Woods yesterday ended his streak of 26 golf tournaments without a win. For most of Woods's career, it seemed the only long streaks he would record would be of the winning variety. But, times have changed.

Saturday, December 03, 2011

Last night on the NHL Network's highlight show, it was pointed out that the Detroit Red Wings have been very streaky in their wins and losses thus far this season. Based on the team's ESPN.com game log, I created the following graphic of Detroit's streaks of wins (red) and losses (grey). If you want to see the little notations for games decided during a five-minute overtime (OT) period or a post-overtime shoot-out (SO), you probably need to click on the graphic to enlarge it.


As can be seen, the Red Wings won their first five games, then lost their next six, and so forth. One of the statistical methods of detecting streakiness is known as the runs test. A "run" is an uninterrupted sequence of entirely wins or entirely losses. The fewer runs a team has, the stronger the evidence of streakiness. After 24 games, Detroit has only five runs. Based on an online runs-test calculator, into which I typed a 1 for each win and a 0 for each loss, the Red Wings' number of runs was fewer than would be expected by chance (with a significance of .00082 for those of you with some statistical training).

In this type of analysis, one must be careful to check if the team's schedule contained stretches of easy or difficult opponents, which could inflate the amount of apparent streakiness. This may be the case to some extent for Detroit, but not totally. During the Wings' string of six losses, two were to Columbus and Calgary, both of which today are in last place in their respective divisions. Conversely, during its current seven-game winning streak, Detroit has beaten some of the league's better teams, such as defending Stanley Cup champion Boston, Los Angeles, and Buffalo. The November 25 win at Boston, in fact, snapped the Bruins' 10-game winning streak.

Saturday, November 26, 2011

On this rivalry weekend of college football, some teams that had lost many consecutive games to a particular opponent have ended their string of setbacks.

Michigan ended its seven-game losing streak to archrival Ohio State, with a 40-34 win in Ann Arbor.

Kentucky, which had lost 26 straight to Tennessee, finally vanquished the Vols today, 10-7.

Baylor snapped a 15-game losing streak to Texas Tech, outscoring the Red Raiders 66-42.

Friday, November 25, 2011

The South Alabama men's basketball team went 0-for-24 on three-point shot attempts last Sunday against Florida State. South Alabama now shares the record for most three-point tries without a make, as Dayton's men also went 0-for-24 behind the arc in a 2008 game. In doing some research today, I discovered that I had previously missed the fact that there is a third school with an 0-for-24 day on treys, namely South Carolina State in 2004.

Sunday, November 20, 2011

Baylor's football team ended the school's 0-for-20 all-time drought against Oklahoma (dating back to the teams' first meeting in 1901) with a 45-38 win over the No. 5 Sooners last night. The Bears also had lost 33 straight to teams ranked in the Associated Press Top 10, since a 1986 win over then-No. 10 Arkansas.

Saturday, November 19, 2011

Hot Hand, the book, is here!




I am pleased to announce the arrival of my new book, Hot Hand: The Statistics Behind Sports' Greatest Streaks. It represents the culmination of many years of writing about sports streaks on this blog and elsewhere. I have picked out what I consider the most interesting streaks I've written about on the blog for inclusion in the book, plus I've added some new stuff. On Amazon.com, you can "Look Inside" for a free preview of Chapter 1 (here's a direct link to Amazon's information about the book).

Friday, November 11, 2011

Gur Yaari, a researcher at Yale School of Medicine, recently notified me of an online article on free-throw shooting and the hot hand that he co-authored with Shmuel Eisenmann. The study focused on whether basketball players have a higher probability of making the second of two free throws after making the first than after missing the first.

The classic Gilovich, Vallone, and Tversky (1985) article failed to find evidence of streakiness in free-throw shooting, but Yaari and Eisenmann noted that they were using a much larger sample than that of Gilovich and colleagues -- 308,862 free-throws taken from 2005-06 through 2009-10 in the National Basketball Association (situations in which shooters were awarded three shots after being fouled behind the arc were studied, but I don't discuss them).

Some of the statistical concepts cited were beyond my expertise, such as the hypergeometric distribution. The basic finding was clear, however. Players made around 72-75% of their free throws (depending on the season) after missing a free throw, whereas they hit on around 76-80% after making the first. The paper is full of technicality and subtlety. The authors precisely characterize their findings as: "essentially that the results are unlikely to emerge from a collection of uncorrelated sequences each with a constant probability of success and no auto correlation."

Yaari and Eisenmann also raised two possible explanations for their findings: what I would consider a traditional hot-hand scenario ("success breeds success and failure breeds failure"); and fluctuations between "better and worse periods." The authors found that players' hotness levels were uncorrelated from season to season, thus going against the idea that some shooters possess inherent streakiness.

The website "Sweat Science" also reviewed the Yaari and Eisenmann study. The review ended with the following call for caution, with which I concur:

...we’re usually referring to time frames that are longer than two back-to-back free throws [for a sequence to be considered a hot or cold hand] ... but far shorter than game-to-game variations. So in the end, I’m going to keep believing that the hot hand doesn’t exist until better evidence emerges.

Sunday, November 06, 2011

This weekend's play in the National Football League had several streak-relevant developments.

The defending Super Bowl champion Green Bay Packers advanced to 8-0 on the season. With wins in the team's final two regular-season games of the 2010 campaign and four postseason games, Green Bay has now won 14 straight.

A team heading in the opposite direction is the Indianapolis Colts, who today fell to 0-9 on the season. It doesn't seem so long ago that the Colts were playing in Super Bowls (following the 2009 and 2006 regular seasons), but with star quarterback Peyton Manning not playing this season due to multiple neck surgeries, the team seems totally adrift.

Whereas the Packers' and Colts' respective streaks continue onward, there were also some streaks that ended today.

The Miami Dolphins won their first game of the season, after starting off 0-7. Adding in losses in their final three games of the 2010 season, the Dolphins had lost 10 straight.

Finally, this Associated Press article on the New England Patriots' loss to the New York Giants notes a couple of streak-ending elements associated with the Patriots' defeat:

The loss ended several impressive streaks: wins in an NFL-record 31 regular-season starts at home for [quarterback Tom] Brady and in 20 regular-season home games for the Patriots.

Saturday, October 29, 2011


The 2011 World Series -- which concluded with last night's rather unexciting St. Louis victory in Game 7, after the Cardinals' dramatic comeback Thursday night over Texas in Game 6 -- had many streak-relevant aspects.

One issue that probably occurred to many people is the apparent momentum that carried over from the Cards' Game-6 win to Game 7 (or perhaps the Rangers' demoralization that did the same). It is an easy enough matter to examine World Series that went seven games to see if the team that won Game 6 seemed to have an increased likelihood of also winning Game 7. This online compilation details the game-by-game sequences of winning and losing teams in each World Series, but runs only through 2004. However, it turns out that the only post-2004 Series to go seven games was this year's. Below, I list all World Series from roughly the last six decades that went seven games (it is admittedly an arbitrary cut-off, but I wanted to have a relatively large sample without the chart getting too long).

YearTeam That Won Game 6
Also Winning Game 7
Team That Lost Game 6
Winning Game 7
1952NY Yankees---
1955---Brooklyn Dodgers
1956---NY Yankees
1957---Milwaukee Braves
1958NY Yankees*---
1960---Pittsburgh Pirates
1962---NY Yankees
1964---St. Louis Cardinals
1965---LA Dodgers
1967---St. Louis Cardinals
1968Detroit Tigers*---
1971---Pittsburgh Pirates
1972---Oakland A's
1973Oakland A's---
1975---Cincinnati Reds
1979Pittsburgh Pirates*---
1982St. Louis Cardinals---
1985KC Royals*---
1986NY Mets---
1987Minnesota Twins---
1991Minnesota Twins---
1997---Florida Marlins
2001Arizona Diamondbacks---
2002Anaheim Angels---
2011St. Louis Cardinals---
*Won final 3 games in coming back from 1-3 deficit.

In total, there were 13 instances of the team that won Game 6 continuing on to win Game 7, and 12 of the team that lost Game 6 rebounding to win Game 7. Pretty even. However, nine of the last 10 times the World Series has gone seven games, the team that won Game 6 went on to win Game 7.

Among the instances of the Game-6 outcome appearing to carry over to Game 7, we have some of the most heartbreaking losses from the perspective of the team that failed to close out the series in six games:
  • The 1986 Boston Red Sox, seeking the franchise's first World Series title since 1918, failing to get one final out to finish off the New York Mets in Game 6, after leading 5-3 with two Mets out and no one on base in the bottom of the tenth. The Mets won in seven.
  • The 2002 San Francisco Giants, leading 5-0 at Anaheim in Game 6 as the Angels came up in the bottom of the seventh, giving up 3 in the seventh and 3 in the eighth to lose 6-5. The Angels won in seven.
  • This year's World Series, in which the Texas Rangers were "one strike, twice" away from closing out the Cardinals in Game 6. A listless Ranger squad then fell in Game 7 by a score of 6-2.

Of course, not all teams that have suffered a near-miss loss in trying to close out the World Series in six games have faltered in Game 7. The 1975 Cincinnati Reds, who squandered a three-run lead in the eighth inning of Game 6 and lost on Carlton Fisk's famous extra-inning homer, did manage to win Game 7.

Another factor to consider is home-field advantage. With the Cards' win last night, the home team has now won nine straight Game 7's.

Other instances of hotness and coldness from the World Series:
  • The Cards' Albert Pujols, who recorded what some consider the greatest offensive performance ever in a single World Series game, blasting three home runs and getting five hits overall in six at-bats during Game 3, went 1-for-19 in the remainder of his official AB's. He thus finished the Series 6-for-25 (he did get on base with six walks, though, five of them intentional).
  • The Game 6 and 7 losses were the first back-to-back defeats for Texas since getting swept three games by Boston on August 23-25. Each of the next 13 times the Rangers lost, they immediately won the next game. (The losses in question were: Aug. 27 to the Angels; Aug. 31 to Tampa Bay; Sept. 3 to Boston; Sept. 5 to Tampa Bay; Sept. 7 to Tampa Bay; Sept. 10 to Oakland; Sept. 16 to Seattle; Sept. 22 to Oakland; to Tampa Bay to begin the postseason; in Games 3 and 5 in the American League Championship Series against Detroit; and finally, in Games 1 and 3 against St. Louis.)
  • Josh Hamilton, the ailing Rangers slugger, ended a drought of 65 postseason at-bats without a homer in the 10th inning of Game 6, with a two-run shot. It looked like it might be enough to give Texas the series, but the Cards tied the game in their half of the inning and won in the 11th.   

Sunday, October 23, 2011

Several streak-relevant developments occurred yesterday:

Texas Tech ended Oklahoma's home-field winning streak at 39 games, in college football.

Also in college football, East Carolina's Dominique Davis completed all 26 of his pass attempts in the first half against Navy, before throwing an incomplete pass to open the third quarter (play-by-play sheet). As noted in the linked Washington Post article, "Davis, a 6-foot-3 senior, completed his final 10 passes last week against Memphis, giving him 36 straight completed passes — eclipsing the season mark of 26 set by [California's Aaron] Rodgers in 2004."

The St. Louis Cardinals have now scored first in 10 straight postseason baseball games, the record for a single postseason (i.e., not allowing a team to combine games from different years' postseasons). Using the Cardinals' game-by-game playoff log, I've charted the innings in which St. Louis and its opponent scored their first runs in each given game (below, you may click on the chart to enlarge it). As can be seen, St. Louis has been scoring a lot in the first or second inning. The Cards will attempt to make it 11 straight games scoring first tonight, in Game 4 of the World Series at Texas.


[UPDATE: The Texas Rangers have scored first in Sunday night's Game 4, thus ending the Cardinals' streak of scoring first.]


Finally, in National Hockey League action, L.A. Kings goalie Jonathan Quick has now recorded three straight shutouts.

Wednesday, October 19, 2011

Baseball's World Series, which begins tonight, features two very hot teams. It's not just the relative ease with which the St. Louis Cardinals and Texas Rangers dispatched their respective rivals in the first two rounds of the playoffs, but also how the Cardinals and Rangers ended the regular season.

At the conclusion of play on August 24, the Cards were only slightly above .500, with a record of 67-63, hardly suggestive of a team that would become the National League representative in the Fall Classic. However, the Cardinals got hot for roughly the last month of the season (winning 23 games and losing only 9, to finish 90-72) while their rivals for the last playoff spot, the Atlanta Braves, got cold over the same period of time (11-21, including 6 losses in their final 7 games) to finish 89-73.

The American League champion Rangers finished the season even hotter than the Cardinals, winning 14 of their final 16 regular-season games to finish 96-66. Texas really fattened up on the worst teams in its division, going 15-4 vs. Seattle and 13-6 vs. Oakland in the regular season. However, any concerns about whether the Rangers could win steadily against better opposition were allayed in the initial playoff rounds, as Texas defeated Tampa Bay 3 games to 1, and Detroit 4 to 2.

Although it's guaranteed to happen this year, teams finishing the regular season on fire usually don't win the World Series. According to a 2005 study:

In the 35 years from 1969 through 2004, the team with best overall winning percentage won the World Series only eight times. Let me emphasize: the team with the best regular-season record has won the World Series only 23% of the time...

How about the teams with the best September record? The answer is exactly the same: they won eight World Series, too. Same impact. In six of the eight examples, however, the team with the best September record was also the team with the best overall record. So there's a lot of overlap between the two groups.

In fact, in about half of the last 35 years (17, to be exact), the team with the best regular-season record was also the team with the best record in September. Of those 17 teams, six won the World Series. Even teams that were Good and had Momentum won it all only 35% of the time.


 This 2006 article elaborates on why late-season hotness or coldness is not necessarily indicative of postseason performance.

Friday, October 14, 2011

ESPN.com writes about the 37-game losing streak of Lock Haven University's football squad, the longest stretch of futility at any level of U.S. college football. Lock Haven plays at the Division II level, a cut below conferences such as the SEC, Big 10, and Pac 12, who play in Division I.

Friday, October 07, 2011

The Texas Tech women's soccer streak of holding opponents scoreless ended tonight at 716 consecutive minutes, as the Red Raiders lost to Texas A&M, 2-0. Texas Tech came into the match not having allowed a goal in the last 670 minutes, as detailed previously. Tech goalie Victoria Esson (right) had been in net for 593 of those minutes.

With a record crowd (including your Hot Hand correspondent) in attendance in Lubbock, the Aggies' Kelley Monogue scored roughly a minute into the second half (i.e., the 46-minute mark) to end the streak (see scoreboard photo below). As also seen on the scoreboard, A&M's streak-breaking goal was also its first shot on goal (S.O.G.) for the evening, so Texas Tech's defense until that time had really stymied the Aggie offense.

The Red Raiders' shutout streak thus ended at 716 minutes, whereas Esson's personal scoreless streak expired after 639 minutes.

Monogue added another goal at the 86-minute mark to produce the final 2-0 margin.

Monday, October 03, 2011

The Texas Tech women's soccer team, with starting goalie Victoria Esson and her back-ups, has now gone seven straight games without allowing a goal (full disclosure: I'm on the faculty at Texas Tech). Regulation time for soccer is 90 minutes, but twice 20 minutes of overtime have been tacked on, bringing the total number of shutout minutes to 670. Based on the Red Raiders' game-by-game log, here's how the streak has unfolded.

Date
Opponent
Score
Esson (min.)
Substitute (min.)
Sept 11
Toledo
3-0
45
Braziel 45
Sept 16
Ariz. St.*
5-0
90
---
Sept 18
Arizona*
0-0
110
---
Sept 23
Missouri
1-0
90
---
Sept 25
N. Arizona
5-0
58
Kaufman 32
Sept 30
@Baylor
0-0
110
---
Oct 2
@Oklahoma
2-0
90
---

*Arizona tournament at Tucson.


According to the NCAA Division I women's soccer record book, the record for consecutive scoreless minutes by a goalie is 1,669:25 -- that's sixteen-hundred and change -- by Anne Sherow of North Carolina, spanning segments of the 1987 and 1988 seasons. That same record book lists 22 stretches of 700 or more minutes by individual goalies.

Esson has not allowed a score in the last 593 minutes she has played. If, hypothetically, she continued to shut out opponents and brought her personal total of consecutive scoreless minutes above 700, I'm not sure if she would make the list in the NCAA record book, because she was not the netminder for all of her team's minutes during that time. Still, I think you can see the magnitude of what Esson and her Red Raider teammates (don't forget those defense players!) are in the process of accomplishing.

Sunday, October 02, 2011

Revisiting the depths of cold hitting in baseball -- the record for non-pitchers' consecutive official at-bats without a hit -- we had Milwaukee's Craig Counsell registering a 0-for-45 slump earlier this season. There was debate at the time over whether Bill Bergen in 1909 had gone hitless in 45 or 46 straight at-bats and thus whether or not Counsell had earned a share of the record.

Upon further review, it turned out that Bergen's streak length was indeed 45 hitless at-bats. The confusion appeared to stem from whether Bergen's number of at-bats in a particular game was 2 or 3, with the number being fuzzy in a photocopied box score. Additional sources of data made it "pretty certain" to a historical analyst that the number was really 2 and thus the overall hitless streak was 45 AB.

Well, as I learned from a SABR electronic newsletter the other day, the Dodgers' Eugenio Velez just finished the 2011 season on a 0-for-46 slump, breaking the prior record. And he can still extend the streak next year!

Wednesday, September 28, 2011

Ichiro Suzuki's streak of consecutive 200-hit seasons is about to end at 10.

Tuesday, September 27, 2011

Nate Silver, who has written mainly about politics in recent years, returns to his baseball roots, examining where in history the September collapse of the Boston Red Sox ranks.

Saturday, September 17, 2011

Defending national college-football champion Auburn had its 17-game winning streak snapped today, with a 38-24 loss to Clemson. Auburn, which started off 2-0 this season, was 14-0 last season and had closed out the 2009 season with a bowl win.

Texas Tech quarterback Seth Doege had the hot hand in leading the Red Raiders to a 59-13 win at New Mexico. According to this game article:

Doege tied a school record by completing his first 15 passes en route to finishing 40 for 44 -- a 90.9 completion percentage, a national record for quarterbacks with at least 40 completions.

Thursday, September 15, 2011

With yesterday's loss to the St. Louis Cardinals, baseball's Pittsburgh Pirates clinched their 19th straight season with a losing (i.e., sub-.500) record. Among major North American sports leagues, the Pirates franchise holds the record for consecutive losing seasons and has for some time.

As discussed here, the NFL futility record (at least for the modern, Super Bowl era) is held by the Tampa Bay Buccaneers, who went 14 years (1983-1996) without a winning season, whereas the NBA mark belongs to the Kansas City/Sacramento Kings franchise (15 years, 1983-84 through 1997-98). In the NHL, the Vancouver Canucks hold the record at 15 straight years of losing (1976-77 through 1990-91).*

Going back to the 2011 Pirates, it looked for a while this season that the team might finally end the streak. As this game article from the loss to St. Louis summarized: "...the Pirates were 51-44 and led the NL Central by a half-game before play on July 20. But they have gone 16-38 since, leaving them at 67-82."

In fact, as the August 1 trading deadline approached, the Pirates became "buyers" (teams within striking distance of the playoffs who trade for players who could put the team over the top) rather than "sellers" (teams that are hopelessly out of contention and trade their veterans to the buyers for young prospects) for the first time in a long while, acquiring veterans Derrek Lee and Ryan Ludwick.

Pittsburgh's trade-deadline moves obviously didn't have the desired effect, but at least they showed the team's fans (all three of them; just kidding) that management was willing to take some initiative when a winning season seemed within reach. Assuming the Pirates end the season with a win total in the low 70s, will they be able to win an extra 10 games or so next year to finally exceed the 81-81 break-even point? I'm skeptical.

 ---
*Vancouver fans didn't exactly go through 15 years of suffering, however. Through the NHL's policy of letting a large percentage of its teams into the playoffs and the historically high upset rate once the postseason begins, the 1981-82 Canuck squad actually made the Stanley Cup finals. This, despite the team's regular-season ledger of 30 wins, 33 losses, and 17 ties.

Saturday, August 27, 2011

Two record streaks in women's sports came to an end last night.

Penn State's women's volleyball team, which has won the last four NCAA national titles, had its 94-match home winning streak ended by Oregon, 3 games to 1. For the Ducks, who've long been in the shadow of Pac 10 (now 12) rivals Stanford, Cal, USC, UCLA, and Washington, this is quite a stunning win.

Meanwhile, out on the left coast, the Tulsa Shock of the WNBA snapped its 20-game losing streak by edging the Los Angeles Sparks 77-75. The veteran Sheryl Swoopes, whose illustrious career includes leading the Texas Tech Lady Raiders to the 1993 NCAA women's basketball title, winning three Olympic gold medals, and capturing four WNBA rings with the now-defunct Houston Comets, hit a buzzer beater for the win.

Friday, August 26, 2011

Jeremy Arkes and Jose Martinez have an article in the latest issue of the Journal of Quantitative Analysis in Sports, purporting to show evidence for momentum in the National Basketball Association. Access to JQAS articles requires a subscription, but guest privileges to look at an individual article are available.

Using data from three recent seasons, the authors find "greater success in the past few games leads to a higher probability of winning the next game" (p. 13). Key to these results are statistical controls for focal teams' and opponents' long-term strength or ability levels (excluding the recent games), home/away status for a given team, and teams' number of days' rest between games. Some of the measures appear conceptually similar to an RPI ranking system, which accounts for teams' strength of schedule.

The study uses fairly complex econometric modeling and presents extensive results in tables. However, the authors distill the findings into easily graspable descriptions. For example, for each additional win a team has in its last 5 games, its probability of winning the next game goes up by roughly 2 to 4 percentage points.

I'm not sure, however, that these findings fit what the average fan would think of as "momentum." To some, momentum would suggest looking at teams that have won 5 in a row (or lost 5 in a row) and seeing how they do in their next game. Saying that a team with 1 win (vs. 0) or 5 wins (vs. 4) in its past 5 games has an increased probability of winning its next game (controlling for all of the aforementioned factors) is much more incremental in nature.

Wednesday, August 24, 2011

The Tulsa Shock of the Women's National Basketball Association (WNBA) has now lost 19 straight games, with Tuesday's defeat against the Minnesota Lynx being the latest. Tulsa's 18th consecutive setback, which came last Sunday, set the league record for longest losing streak. The Shock is now 1-24, with nine games left on its schedule.

Friday, August 19, 2011

Amidst the hubbub over allegations of improper benefits given to players by a booster at the University of Miami, Noel Nash of ESPN's Stats & Information Group has notified me of an unusual streak by former Hurricane football players at the pro level. For more than eight years now, a player who attended college at Miami "has scored a touchdown in every regular season week in the NFL...  a span of 139 game weeks."

Sunday, August 14, 2011

Dan Uggla's hitting streak ended at 33 games this afternoon, as his Atlanta Braves fell to the Chicago Cubs, 6-5. Much was made of Uggla's low batting average prior to the streak and how unlikely it seemingly made the streak. In my view, judging the likelihood of Uggla's hitting streak is not so simple.

Let's start with a refresher on some principles of probability. Batting average represents a player's probability of gettting a hit in any given official at-bat. Where consecutive-game hitting streaks are concerned, we're interested in the probability of a player getting at least one hit in a game. The latter will generally be a higher probability than the batting average because the player usually will have multiple official at-bats in a game.

To estimate the probability of a player getting at least one hit in a game, statisticians typically assume a number of official at-bats per game for the player and further assume independence of outcomes (i.e., that what happened on one at-bat has no effect on a later at-bat). As of the conclusion of yesterday's play, Uggla was getting 3.76 official at-bats (AB) per game (448/119). Looking at Baseball Reference's wonderful game-by-game log for Uggla this season, he had a few games (mostly prior to the streak) with 0 or 1 plate appearances, suggesting he appeared as either a late-inning defensive replacement or pinch hitter in a few games. Assuming regular starts, which would be the case well into a hitting streak, we could estimate he'd have 4 AB per game.

Whereas batting average (BA) is the probability of a success (hit) in a particular official at-bat, the probability of failure in that at-bat, F = (1 - BA). The probability of an all-failure (no hits) game with 4 AB is simply F raised to the 4th power. Getting at least one hit means avoiding an all-failure game, so the probability of getting at least one hit is:  1 - (F^4). To know F, we need to know BA, and that is where the difficulty arises with Uggla.

The day Uggla began his hitting streak (July 5), he woke up with a .173 BA. During the streak, he hit .377 (49/130). Upon completion of his last game during the streak (i.e., yesterday's), his season-to-date average sat at .232. And, while we're at it, his lifetime BA (excluding 2011) is .263. The question is, which batting average should we use to best capture his batting ability, let's say, midway through the hitting streak? Another way to think of the problem is that, Uggla's hitless game today notwithstanding, we wanted to know what BA to use for him in predicting his chances of getting a hit in his next 23 games, to tie Joe DiMaggio's record of 56 games.

The following table runs through the steps of transforming an Uggla batting average into his estimated probability of getting at least one hit in his next 23 games.

p(Hit in 1 AB)
[Batting Avg]
p(Failure in 1 AB)p(Failure in
All 4 AB)
p(>/= 1 Hit
in 4 AB)
p(Hit in All of Next 23 Games)
.173.....................827...........468.....................532.....................0000005............
.377.623.151.849.023
.232.768.348.652.00005
.263.737.295.705.0003

Even under the most advantageous assumption for Uggla -- namely taking his batting average exclusively from his recent streak -- the chances of tying DiMaggio would be only about two percent. Still, which batting average should we use?

As shown in the book Scorecasting by Moskowitz and Wertheim, a baseball player's batting average over the past two seasons is a better predictor of success in the next at-bat than is batting average over the last five plate appearances, last five games, the last month, or season-to-date. Thus, going by the principle that large sample size trumps recency, Uggla's lifetime batting average would appear to be the best of the above options in predicting his future hitting streaks.

Another factor that helped Uggla in putting together the 33-game hitting streak was his low walk rate. At the close of yesterday's play, he had only 39 bases on balls, so that his number of official AB (448) was not that much lower than his total plate appearances (494). A tendency to draw a lot of walks can really short-circuit a hitting streak because a player may only get 1 or 2 official AB per game, thus giving him few opportunities to get a hit (if a player walks in all of his plate appearances in a game, however, a hitting streak continues). As Joe D’Aniello wrote about in the Baseball Research Journal (Vol. 32, 2003) in conjunction with his examination of DiMaggio’s hitting streak, a key reason why Ted Williams never contended for a long hitting streak was his propensity to draw walks. 

David Rockoff and Phil Yates, writing in the Journal of Quantitative Analysis in Sports, identified as a flaw in statistical formulations of hitting streaks the assumption of the same number of at-bats per game (as I did above in making calculations based on 4 AB per game for Uggla). In real life, as noted above, a player may get only 1 or 2 AB in some games, thus harming his chances to extend a hitting streak. In Uggla's case, however, his rate of walks (and other plate appearances not resulting in official at-bats) is so low as to largely avoid the problem stated by Rockoff and Yates, in my view.

Tuesday, August 09, 2011

Sunday, August 07, 2011

Here are some brief streakiness-related items, all from baseball.

*With today's win over Seattle, the Angels have now won 13 of their last 15 series (game-by-game log). The exceptions to the series wins are a 2-2 split at Detroit July 28-31; and the loss of 3-of-4 at Oakland July 15-17 (including a doubleheader).

*Today against the New York Mets, one member of the Atlanta Braves extended a hitting streak -- Dan Uggla, to 28 games -- whereas another, Freddie Freeman, saw his 20-game hitting streak end (article).

*A little over a week ago, two hitting streaks in the mid-20s ended: Emilio Bonifacio's (Marlins) at 26, and Dustin Pedroia's (Red Sox) at 25.

*Last Friday night, Milwaukee's Craig Counsell finally got a hit after 45 official at-bats without one. According to this article, "Some claimed Counsell tied the modern baseball record (since 1900) for a position player when he popped out to second base Monday against the St. Louis Cardinals. Others claimed the actual record was 0 for 46, set by Brooklyn catcher Bill Bergen in 1909."

*In getting swept by the Yankees in a four-game series (August 1-4), the Chicago White Sox didn't get a single walk offensively. It had been 43 years since the White Sox last went without a walk for four straight games. New York's pitchers may have had a hot hand when it came to throwing strikes, or maybe the Chicago batters just had impatient hands.

Wednesday, July 27, 2011

The Seattle Mariners have ended their losing streak at 17 games, with a 9-2 win today over the New York Yankees.

Frank Vaccaro, one of the streak experts in the Society for American Baseball Research (SABR), recently informed members what the longest baseball losing streaks of all time are. Restricting the list to 1900 and beyond, the longest losing streak was 23 by the Philadelphia Phillies in 1961. The 1988 Baltimore Orioles lost 21 straight, with the added twist that the losses were to start off the season (i.e., the O's had an 0-21 record at one point).

With their skid now concluded at 17 games, the 2011 Mariners officially have ended up tied for 23rd place in the all-time rankings for longest major-league baseball losing streaks (tied for 14th if one excludes teams from before 1900).

UPDATE: Jesse Wolfersberger at Fan Graphs estimates the probability of the Mariners' 17-game losing streak, using betting odds to derive the game-specific win probabilities. After the game-specific projections are converted to loss probabilities (1 - Win Prob), they are then multiplied together. A lot of commenters chime in on Wolfersberger's analysis, too.

Saturday, July 23, 2011

The Seattle Mariners have now lost 14 games in a row, the longest losing streak this year in Major League Baseball. According to ESPN Stats & Information, the longest skid in the past 15 years is 19 games, by the 2005 Kansas City Royals. Before going on the 14-game losing streak, Seattle was actually a .500 team (43-43). However, the Mariners have lately been facing some of the better teams in the American League, such as the Angels, Rangers, and Red Sox (see game-by-game log). Seattle has one game remaining at Boston in the teams' current series, and then a three-game stand at Yankee Stadium, so an end to the losing streak may not be imminent!

Saturday, July 16, 2011

With baseball's Texas Rangers on a winning streak that reached nine games last night (including shutouts in the last three contests), Gary Collard sent a message to the Society for American Baseball Research (SABR) listserve discussion group, noting the weak opposition faced by Texas in recent weeks:

"The Rangers ended the pre-All Star break portion of their schedule by playing 16 of 19 games against last place teams. I think this is probably a record, since you would pretty much have to have two interleague series against your 'designated rival' to hope to match it (6 divisions is likely a must as well)."

The reference to a designated rival, in this case, describes the Rangers' six games against the Houston Astros (last place in the National League Central) on June 20-22 and 28-30, as a special geographic match-up during interleague play. Other last-place teams played by Texas include Florida (NL East, July 1-3), Baltimore (American League East; July 4-6), and Oakland (AL West, July 7-10). Also, the Seattle Mariners, against whom the Rangers have won the first two games of a current four-game series, are only slightly better than last in the AL West. The Rangers' last loss came in the finale of the Florida series.

Tom Ruane followed Collard's SABR message with one of his own. Because divisional play didn't begin until 1969 (prior to that, there only would have been two last place teams at a given time, one each in the AL and NL), Ruane used a different approach, focusing on opponents with poor records. One of Ruane's findings was that four times since 1900 has a team played 19 straight games against teams with winning percentages below .400. The most recent such team was the San Francisco Giants, who did so from May 21 to June 10, 2004, going 13-6.

My curiosity piqued, I decided to look up the Giants' streak myself. During the stretch, San Francisco played two games against the then-Montreal Expos (whose winning percentage was around .333 at the time); seven against the Arizona Diamondbacks (who peaked around .38 during these games); seven against the Colorado Rockies (who peaked around .39); and three against the Tampa Bay Rays (around .39).

Last January, I found a basketball analogue to the current Texas Rangers' situation, namely how a 19-out-of-20 winning stretch by the Miami Heat involved very few games against the NBA's best teams.

Wednesday, July 06, 2011

U.S. women's soccer goalie Hope Solo had her streak of 796 minutes without allowing a goal end today, in the Americans' 2-1 loss to Sweden in the women's World Cup (90 minutes is the regulation game length). The streak-ending goal came on a penalty kick, which is a special type of play that is especially difficult for the goalie to defend. However, Sweden scored again roughly 20 minutes later, so Solo's streak would have ended in the same game (albeit a little further along), even if we exclude penalty kicks.

Wednesday, June 29, 2011

Roger Federer hasn't been winning Grand Slam tournaments lately, but one way he appeared to be unassailable was when he won the first two sets (in a 3-out-of-5 format) in one of the Slam events (Wimbledon and the Australian, French, and U.S. Opens). Before today, in fact, he was 178-0 when ahead two sets to none in a Grand Slam event. That streak is now over, as Federer lost at Wimbledon to Jo-Wilfried Tsonga, 3-6, 6-7 (3), 6-4, 6-4, 6-4.
In winning its second straight NCAA College World Series baseball championship Tuesday night, the University of South Carolina established a number of streak-related records.

Since a 1999 expansion of the tournament to 64 teams, the format has consisted of four phases, each double-elimination. First, the 64 teams are divided into 16 regional sites of four teams each. The winning team in a regional will either have a 3-0, 3-1, or 4-1 record. The 16 regional winners are then paired off into eight super-regionals, each a 2-out-of-3 series. The eight super-regional winners then go to the College World Series, with preliminary rounds (again double-elimination) producing two finalists. The final championship series is again 2-out-of-3.

According to this article on the Gamecocks' 2011 title, South Carolina "became the first team to ever go 10-0 in an NCAA [baseball] tournament." The team went 3-0 in the regionals (beating Georgia Southern once and Stetson twice), then swept two from Connecticut in the super-regional. A 3-0 run through the World Series early rounds (beating Texas A&M once and Virginia twice) landed South Carolina in the final round, where it swept Florida, 2-0 (2011 game-by-game log).  

Last year, South Carolina dropped its World Series opener, before rebounding for four straight wins to make the championship finals. The Gamecocks then swept UCLA, 2-0, to capture the title. Adding South Carolina's closing six victories in last year's World Series to this year's 10 straight wins in the overall postseason and five straight in the World Series yields some monster streaks.

As above-linked the article on South Carolina's 2011 championship notes, "The Gamecocks' streaks of 16 NCAA tournament wins and 11 straight in the CWS are both the longest all-time."

Wednesday, June 22, 2011

Talk about a fast start offensively to a baseball game! According to MLB.com:

In the top of the first inning Tuesday, the first eight Minnesota Twins hit safely, alternating singles and doubles. With those eight straight hits to begin the game, the Twins tied a Major League record accomplished six times before.

(Thanks to David Vincent, whose message to the Society for American Baseball Research [SABR] discussion group brought the Twins' streak to my attention.)

Sunday, June 19, 2011

Rory McIlroy maintained his torrid pace all the way through the men's U.S. Open golf tournament, ultimately winning at 16-under-par (see Friday's posting, immediately below, for background). Second-place Jason Day, who finished 8 strokes behind McIlroy, went bogey-free (i.e., made par or better) on his final 45 holes.

***

Baseball's Florida Marlins are now 1-18 for the month of June. Manager Edwin Rodriguez resigned before today's loss.

Friday, June 17, 2011

Northern Ireland's young Rory McIlroy tends to have a hot hand in the early rounds of the major men's pro golf tournaments, as I've graphed below (data source). However, he also sometimes goes erratic. He's done really well in his first two rounds of the U.S. Open, which is currently ongoing, achieving par or better on the first 35 holes he played, before double-bogeying the 36th (18th hole of Round 2). We'll see if he can retain his spectacular form on Saturday and Sunday to score his first victory in a major.

Thursday, June 16, 2011

The following announcement of a major home-run streak appeared at the beginning of June, as part of ESPN.com's collaboration with the Elias Sports Bureau:

Jose Bautista finished the month of May with 11 home runs, the most in the American League. It was the fifth straight month in which Bautista led the A.L. in homers (excluding March and October). Bautista led the American League in homers in July, August and September of 2010 and in April and May of 2011. The last player to lead a league in home runs (outright or tied) for five consecutive months was Jimmie Foxx. Foxx led the A.L. in homers in June, July, August and September in 1933 and in April in 1934.

Naturally, an accomplishment for which one must go back 77 years to find an equal is quite noteworthy -- especially when that equal is the caliber of Hall of Famer Jimmie Foxx. Still, the above report of the record by Toronto right-fielder Bautista raised some questions in my mind.
  • Was Bautista merely squeaking by with his monthly home-run leads or was he blowing away the competition?
  • As I eventually came to realize, the report carefully qualifies the record in terms of Bautista's leading only the American League or leading "a league" in home runs during particular months. So, during how many of these months did he lead Major League Baseball overall in home-run output?
  • The report also notes that March and October were excluded. If one were to add March totals to April's and October totals to September's, would that change the conclusions? 
Using the superb Home Run Tracker website from ESPN's Stats & Information Group, I reviewed all MLB hitters' home-run output during 2011 and all American League hitters' homers for July onward in 2010. Each home run is documented on its own line of data and the lines can be sorted by hitters' names. I simply perused down the screen, counting a given hitter's homers by month only when it looked like he had a sizable number of blasts (I overlooked 2010 NL data in the interest of time). The following chart presents the fruit of my labor (you may click on the chart to enlarge it, realizing that the top and bottom parts are separate, due to size limitations).



The first finding to notice is that Bautista's margins in leading the AL during July, August, and September of 2010 were pretty comfortable. No other AL players (barring anyone I missed in my "retinal inspection" of the Tracker data) hit double-digit homers in a month. Bautista's smallest margin was 2, as Yankees Curtis Granderson and Alex Rodriguez each clouted 9 homers in September, compared to Bautista's 11. (I have highlighted cells of particular interest in light green.)

It is during 2011 that things are more interesting, in my view. In April, Bautista's 9 dingers were surpassed by National Leaguer (Cub) Alfonso Soriano's 10. If we add National Leaguer (Brewer) Ryan Braun's 1 March homer to his 9 from April, he would also exceed Bautista. Yet another NL player, Cincinnati's Jay Bruce, exceeded Bautista in May, 12 to 11.

As the chart shows, if Bautista is to lead the AL again in June, he really needs to get going, as he's been in a slump lately. Fortunately for the Toronto slugger, no one else in the league has pulled away in June homers, with Texas's Nelson Cruz and Boston's David (Big Papi) Ortiz leading with 5 each. (Note that some of the June 2011 homer totals may be slightly outdated at the time of this posting Thursday afternoon, as I did the bulk of my tabulating Wednesday morning.)

For what it's worth, Bautista's home field, the Rogers Centre, currently ranks as one of the more hitter-friendly venues in MLB, according to "Park Factor" statistics.

In conclusion, although there are some reasons to chip away a little bit at the magnitude of Bautista's accomplishment, a first-in-77-years record speaks for itself.

Monday, June 13, 2011

In their NBA title-clinching, Game 6 win over the Miami Heat last night, the Dallas Mavericks put on their usual flurry of scoring spurts (play-by-play sheet). Most dramatic was a Mavs' 17-2 run, which took them from trailing 22-15 to leading  32-24 near the end of the first quarter.

Dallas's DeShawn Stevenson, whose three-pointer put an exclamation point on the 17-2 run with 0:24 remaining in the first quarter, hit a pair of additional threes shortly thereafter, with 10:06 and 9:41 left in the second quarter, increasing the Mavericks' lead to 40-28. The Heat responded with a 16-1 spurt of their own (the Mavs' only point coming on a technical-foul free throw), to go up 44-41.

Miami had little firepower the rest of the way, enabling Dallas to use more modest-sized runs -- 7-0 (from down 49-46 to up 53-49), 8-0 (from down 56-55 to up 63-56), and 8-0 (to expand an 81-77 lead to 89-77) -- to pull away.

Saturday, June 11, 2011

For the third straight year, Texas A&M has swept the men's and women's team titles at the National Collegiate Athletic Association (NCAA) track and field championships.

Thursday, June 09, 2011

Did Dallas have another big spurt late in Game 5 of the NBA finals? Of course it did. In immediate response to a 9-0 Miami run that put the Heat ahead 99-95, the Mavericks closed out the game on a 17-4 run to prevail 112-103 (fourth quarter play-by-play sheet). The Mavs, who also made 13-of-19 three-point attempts (68.4%), now lead the series 3-2.

Tuesday, June 07, 2011

Another game in the NBA finals, another late Dallas spurt. Trailing to Miami 74-65 with a little over 10 minutes remaining in the game, the Mavericks went on a 17-4 run to take the lead, 82-78 (play-by-play sheet). Dallas held on for an 86-83 victory, tying the series at 2-2.

Sunday, June 05, 2011

The Miami Heat held on for an 88-86 win over the Dallas Mavericks, despite a 15-2 run by the Mavs in the third quarter. Miami now leads the NBA finals 2-1.

Friday, June 03, 2011

The following chart says it all, as Novak Djokovic has fallen to Roger Federer in the semifinals of the French Open. You may click on the graphic to enlarge it.

Thursday, June 02, 2011

In a game that was as full of team spurts as any you'll see, Dallas stunned Miami tonight to even the NBA finals at a game apiece. With the Heat leading by a seemingly comfortable 88-73 well into the fourth quarter, Jason Terry scored with 6:18 left to launch an improbable 20-2 run that put the Mavericks ahead 93-90 with 26 seconds remaining. After Miami tied the game with a three, Dirk Nowitzki hit a layup in the closing seconds for a 95-93 Mavs win (play-by-play sheet).

The Heat's 88-73 lead itself was the product of a Miami 13-0 burst. Miami also enjoyed a 15-1 run spanning the second and third quarters, converting a 51-42 deficit to a 57-52 lead.

Tonight's game also was the reverse of a classic game in the 2006 NBA finals, also between Dallas and Miami. The Mavericks, leading two games to none at the time and seemingly en route to a 3-0 lead, blew an 89-76 lead with 6:33 remaining, to lose 98-96 (fourth quarter play-by-play). Dallas never won another game in the series that year...

UPDATE: Neil Paine at Basketball Reference has more on Dallas's comeback.

Tuesday, May 31, 2011

Novak Djokovic's quarter-final opponent at the French Open, Fabio Fognini, defaulted before ever taking the court, a result of Fognini's grueling (though victorious) match in the previous round. The default win does not count as part of Djokovic's winning streak, which remains at 43 (41 to start the 2011 season). Djokovic next faces Roger Federer Friday in the semi-finals.

Sunday, May 29, 2011

Novak Djokovic wins again at the French Open, putting him in the quarter-finals. Here's the updated chart (on which you may click to enlarge):

Saturday, May 28, 2011

Novak Djokovic has won again, taking his darkness-suspended third-round match in the French Open against Juan Martin del Potro. Here is the updated chart, which you may click to enlarge.


Friday, May 27, 2011

Earlier this week, the University of Florida won the NCAA women's tennis team championship, defeating host school and No. 1 seed Stanford, 4-3. According to this article:

The second-seeded Gators (31-1)... end[ed] top-seeded Stanford’s (28-1) NCAA-record 184 consecutive home-match win streak and its 47-match overall win streak. Stanford has not lost at home since Feb. 27, 1999 in a 5-4 loss to Cal and had not dropped a decision since a loss at UCLA on Feb. 26, 2010.

Halting Stanford's 12-year home winning streak did not come easily for Florida. In what turned out to be the decisive match, the Gators' Lauren Embree came back from 4-0 down in the third set to win.

Thursday, May 26, 2011

When evaluating the magnitude of a given streak, it is important to consider the streak's precise definition. Rarely is such attention to detail more important than in the current pitching struggles of Toronto's Jo-Jo Reyes. During Reyes's skid, his official win-loss record has been 0-13, far short Anthony Young's mark of 0-27 during stretches of the 1992 and 1993 seasons. Yet, Reyes is taking plenty of grief in the sports media.

The key to understanding the attention being garnered by Reyes, in my view, is the fact that pitching wins and losses are not exhaustive categories. In other words, a pitcher can be credited not only with a win or loss for a given stint on the mound, but also a no-decision (other categories, such as save and hold, are available for relief appearances). If we say a pitcher has a "losing streak," we're talking about repeatedly getting an actual "L" on the scorecard. If we say that a pitcher has a "winless streak," on the other hand, we're talking about all outcomes other than a "W," primarily L's or no-decisions.

Young's streak was a losing streak -- the number of consecutive times he received a loss decision in games where he got some kind of official W-or-L decision. By this definition, he lost 27 consecutive games.

In Reyes's case, his dubious achievement consists of starting 28 consecutive games and not coming away with a win in any of them -- in other words, a winless streak. This length of winless streak is a major-league record, which Reyes now shares with two other pitchers. By failing to win in his next start (if Toronto will start him anymore), Reyes would hold the record all by himself. As noted above, Reyes has a win-loss record of 0-13 during his streak, but in theory, it could be 0-0 if he had 28 straight no-decisions.

I have created the graph below with the aim of clarifying the situation. It shows all of Young's and Reyes's pitching appearances (in many of which they were sent to the showers) during their respective streaks. You may click on the graph to enlarge it.


The data come from the website Baseball Reference (Young 1992, 1993; Reyes 2008, 2009, 2010, 2011).

Young's 27 losses fell within the scope of 79 consecutive games he pitched, spanning two seasons, in which he never achieved a win. As can be seen, he had a bunch of no-decisions and, on a positive note, some saves in a relief role. There clearly were games during the losing streak during which Young pitched well and easily could have gotten a win with better luck (here and here). But with a starting hurler's prospects for a win or a loss partially under the control of the hitters and relief pitchers on his team, a good showing on the mound isn't necessarily enough for a win.

Early in Reyes's streak, he suffered a string of five losses in five starts. Ever since, his losses have tended to come not in bunches, but sporadically, amidst large numbers of no-decisions.

What to conclude about these two pitchers? In Young's favor, his loss total during his doldrums tells us that he was the pitcher of record when the opposing team scored its winning run(s) about a third of the time (27/79), whereas for Reyes, the figure is nearly one-half (13/28 starts). Also, whereas Young did not achieve any wins during his streak, he did achieve the objective his team gave him -- holding or saving a lead -- during some of his relief appearances.

Because of his predominant role of starter, Reyes cannot be said to have achieved his and his team's objective of winning games; he may have successfully kept his team in contention some of the time, however.

Further parameters, such as each pitcher's actual numbers of earned runs allowed and run support from his teammates, are necessary for a more complete evaluation of what happened with Young and what is currently going on with Reyes. However, such elements are beyond the scope of the current posting and will need to be revisited later.

***

Fittingly for an NBA playoff season that has featured many dramatic scoring runs, the Miami Heat outscored Chicago 18-3 over the final three minutes Thursday night to edge the Bulls, 83-80, and capture the Eastern Conference finals in five games.

Wednesday, May 25, 2011

Novak Djokovic won his second-round match in the French Open and 41st straight match overall, warranting the following update to the Djokovic win chart (click on the chart to enlarge it and here for background information).

Tuesday, May 24, 2011

A multi-sport day of streakiness-related news...

The Oklahoma City Thunder laid another egg against the Dallas Mavericks last night, in the NBA Western Conference finals. Leading 99-84 with roughly five minutes left in the game, OKC gave up a 17-2 run, which sent the game to overtime. There, Dallas took over and won 112-105, giving the Mavs a 3-1 series lead.

***

St. Louis Cardinal slugger Albert Pujols ended a massive home run drought. According to this article: "Pujols had gone 105 at-bats, and 119 plate appearances, since his last home run on April 23. Both were the longest homerless streaks of his career." A whole month for Pujols without a homer? Amazing.

[Update. Kevin Lai, writing at Hardball Times, provides a sophisticated statistical analysis of Pujols's drought.]

***

In looking over the website for the French Open tennis tournament, I noticed that the statistical features for following a given match include a "Momentum Meter" from IBM (apparently, this feature has been around for a few Grand Slam tournaments already, but I just noticed it). Here's an example, from an early-round French Open women's match. As can be seen, each player's momentum is graphed from the beginning to the end of the match, sort of like the stock market's value during the day. Certain plays are picked out as "turning points."

I did some searching of the web to try to learn how momentum and turning points are defined, but I didn't find a whole lot. According to this article, the Momentum Meter displays "an overall swing of player success, calculated algorithmically from match data... [when] a player is particularly on top of their game, [exhibiting fewer] unforced errors, holding their service games [,] etc." I'm particularly curious about whether turning points are determined by some mathematical analysis of inflection points in players' momentum values or subjectively by a rater.

Monday, May 23, 2011

With today's first-round win in the French Open, Novak Djokovic extended his overall winning streak to 40 and his 2011 season-opening streak to 38. This ESPN.com article includes a chart of the longest men's winning streaks in tennis's Open Era (i.e., from 1968 onward, when professionals were allowed into the Grand Slam tournaments).

The longest overall streak is 46, set by Guillermo Vilas from July-September 1977. The longest streak to open a season is 42, set by John McEnroe in 1984.

Djokovic's website has a match-by-match log, which I've used to create to the following graphic (you may click on it to enlarge).

Sunday, May 22, 2011

Consistent with the team's name, the Oklahoma City Thunder created a lot of loud, banging noises in its 93-87 loss to the Dallas Mavericks last night. Hitting only 1-of-17 on three-point attempts, the Thunder thus clanged a lot of distant shots off the rims! Dallas now leads the series 2-1.