Thursday, October 11, 2007

Let's go Tribe!

With the Phils' early departure from the postseason, a Phillies fan is now left with no obvious rooting interest. It's hard to find a reason to object to the Diamondbacks, and there's really nothing wrong with the Rockies, even though they ended our season. The Indians aren't inherently likeable or dislikeable either, while you're likely to either love or hate the Red Sox. From a Phillies perspective, no teams that we hate are really left, so who to root for?
I'm pulling for the Indians. ESPN and FOX and even MLB itself have turned the sport into the Bosox-Yankees show. For the past decade, these two teams really have been remarkable, their fans really get into it (how could you not, with those lineups?), and their rivalry has been fun to watch.
As marketable and, at times, fun as this rivalry has been, however, there is more to baseball. There are other hardcore fans out there, and there are other excellent teams.
None of whom are better than the Indians. It would be one hell of a statement if a low-budget, small-market, almost exclusively home-built team were to sink the Yankees and the Red Sox and then win the World Series. What better way for the rest of baseball to marginalize this rivalry than to bury names like Clemens, Jeter, Ortiz, and Schilling under names like Asdrubal, Sizemore, and CC?
Billy Beane has done a great job showing that there can be great baseball far from the heart of the sport. Unfortunately, all of his teams have been foiled at some point along the way. Let's hope the Indians can finish the job. They can show everyone that not only can a non-NYY/BOS team win the World Series, but it can be legitimately better, too.

Tuesday, October 2, 2007

BYAAAH!!

It's like the baseball gods tortured me for the past decade just to prove that they could make it up in 1 weekend.
The Phils are in the playoffs, and in most memorable fashion.
The Mets did not win the division, and they did not make the playoffs at all.
The Suckdres fell quicker than characters in Family Guy (the animators cut out frames when people in that show fall to make it more sudden and funny). My last post was a whining rant about how the Padres, whose playoff clinch seemed imminent, shouldn't be in the playoffs. And then, somehow, it didn't happen. Something I wanted actually happened!
Sure, I would have preferred to play San Diego than Colorado, but seeing that collection never-was-nor-will-be-nor-could-be position players crumble after watching them celebrate their ridiculous wins was just too satisfying.
Congrats Phillies! You earned it! The Mets may have dropped off completely at the end, but your 13-4 made it relevant.
A special thank you to those Phillies who contributed but will not be on the postseason roster. We'll miss you (you in particular Geoff).

Wednesday, September 26, 2007

Tragedy Strikes

A string of truly tragic murder sprees has just taken place throughout MLB.


Every Yankee position player other than Alex Rodriguez and Robinson Cano has been murdered execution style.

In Atlanta, the Braves position players were brutally murdered via hanging. The only survivors are the oft-injured left side of the infield, Chipper Jones and Edgar Renteria.

In the tragedy that strikes closest to my heart, every Phillies position player other than the dynamic duo of Chase Utley and Jimmy Rollins was slaughtered (Ryan Howard is actually still live, of course, but he's off hunting the perps).

Finally, the only two non-pitching Mets still breathing are David Wright and Carlos Beltran.

What do these 4 tragedies have in common beyond the fact that they are clearly directed at MLB teams? Well, now the offenses of those 4 teams are equivalent, within a few runs over the course of a season, to that of the San Diego Padres.
The potentially playoff-bound Padres have accumulated a total offensive VORP of 134.4 to his point in the season, a total approximately equaled by A-Rod and Cano (129), Chipper and Renteria (123.2), Rollins and Utley (130.6), and Wright and Beltran (126.1).
Now, of course, there are two sides to the baseball coin, and the Padres pitch very well, but COME ON!!! I've seen players in the Pacific Crackhead League (High-A ball) hit better than Marcus Giles and Khalil Greene, who by the way have combined for over 1000 plate appearances and an astounding 11.8 VORP. The Phillies' Pat Burrell, who has hit well for 2 months this season and some would say (though I believe, incorrectly) that he has hit well for 2 months in the last 4 years, would be the most valuable hitter on the Padres, as his 34.7 VORP exceeds that of Pads' team leader, Adrian Gonzalez (31.4). Pat is the Phils' 5th most valuable hitter by this metric (which by the way, is park-adjusted, meaning the difference between PETCO Park and Citizens Bank Park is accounted for).
If the Padres were smart, here's what they would do: euthanize every position player on the team, skin them, and then use the skin and bones to create a protective, armor-type sheath for Jake Peavy's arm, because that's what separates them from the Pirates, despite what a baffling string of ludicrous late-inning victories might say.

Sunday, September 23, 2007

Baseball's bubble

In an article on Baseball Prospectus last week, Nate Silver said he believes baseball is on (or in? I don't know the terminology) a financial bubble right now, one that he thinks will burst in the foreseeable future. The gist of the article was, teams lavish huge contracts on some of these players that make no financial sense.
Take the Astros' signing of Carlos Lee to a 6-year $100 million deal. This year, and for the next 5 years, they will be paying him about $16 million. How much has he made for them this year? Well, if they had signed a replacement level player, according to BP, they would be a 65ish-win team as opposed to a 70ish-win team. First off, this shows some poor baseball decision-making, as they certainly wanted more than a 5-7 win boost for $16 million.
It was also a poor financial decision. Those 5 extra wins likely did not put many extra fans in the seats - perhaps the very presence of a big-money free agent sold some tickets and maybe they sold a lot of "Lee" t-shirts, but it's hard to imagine Carlos Lee added $16 million in revenue to the Stros.
The deal gets worse than that. What if instead of a defensively-retarded, slow corner outfielder with little plate discipline, the $16 million had gotten the Astros Babe Ruth? They would probably be an 80ish-win team instead of 70ish. And guess what. That wouldn't be worth $16 million either.
There is a very simple idea that BP illustrated very eloquently in Baseball Between the Numbers that essentially says that the wins that get you into the post-season are worth a ton of money; those that do not are not. Wins #87-93 bring you from a slight chance of making the postseason to an excellent chance, so they are worth a ton of money because there is so much money to be made from a playoff appearance (the extra sellouts, the boost in fan support, TV ratings). Wins #65-80 raise you from bottom-feeding to mediocrity, which is undoubtedly worth some money, but those 15 wins don't nearly stack up to just a handful of wins in the high 80s or low 90s.
For a bad team to spend lots of money on a free agent, especially one that's not very good, is financial foolishness. The Lee deal along with the Zito deal are probably the most extreme cases, but they are part of a larger problem of teams not doing a good job of understanding how much money these players are really worth.
Every other industry measures a business's success in monetary profits. Baseball teams are measured in wins. If only this were true, but the money being given to these players and the money needed to advertise and run the stadiums is not Monopoly money - it's real. That means that for the sport to function, teams have to earn sufficient revenue, but as we've seen, big free agent signings, along with many post-arbitration free agent signings, don't earn the money back. Perhaps a World Series championship is enough to erase some big contracts, but too many teams do too much spending without enough winning.
One day, an ownership group is going to try to sell its team and find that potential investors have run some numbers and have valued the franchise far below the asking price. If you expect someone to pay the last 5 years of a declining Carlos Lee's contract, you can count on them asking you to knock a lot off your asking price. And what if your team is paying wheelbarrows-full of money to Barry Zito, Randy Winn, Pedro Feliz, and Bengie Molina?
Is this evidence of a need for a salary cap? That's hard to say. It's very objectionable to allow a limit to be set on how much a firm has to pay its laborers. Thus, I'd like to say that a bubble burst would be the owners' own damn fault and that they have to be able to restrain themselves from bidding salaries up beyond the point that's economically efficient. They should be able to determine how much a player can be worth to them and just firmly decide not to go above that figure. Perhaps even structure contracts so that the incentives have to do with team performance, not individual performance, so that a team could ensure that it only pays out the full salaries when it is making a lot of money.
But I'm not sure teams can restrain themselves. If the Phillies decide they want a given starting pitcher for 3 years @ $10 mill/year, but then it turns out their choices are to sign him for 4 years @ $12 mill/yr or not sign him at all, can we blame them for overpaying? The scarcity and volatility of baseball players puts the owners at a lot of risk, so perhaps they are worthy of protection via salary cap.
The way I see it, though, the really dangerous parts of bad contracts are the late years of long deals. How bad might Carlos Lee be in 5 years? There's a decent chance he won't be qualified for a starting role, yet the Astros will be paying him $16 million. As bad as the deal turned out this year, it will actually be like Drayton McClane flushing money down the toilet in 2012.
I think that rather than imposing a regular salary cap, MLB needs to limit the length of free agent contracts. All costs are variable (and thus correctable) in the long run, so if we shorten the duration of the short run, from 5-7 years to 3 years, baseball teams will be able to be much more efficient. This of course would hurt the players, whose big moneymaking time would be shortened, but if the bubble bursts and nothing is done to correct it, the implications would be far worse. The fact is, players are making far more than they should. They should quit while they and their industry are ahead and accept creative ways to lessen their contracts. I believe that in limiting contract length, you could allow players to continue to make a pretty penny while helping the owners cut costs. The only losers would be those players who earn a lot in unproductive seasons that teams got suckered into committing to.
If MLBPA agrees now to changes that will help owners out, even at the short-term expense of the players, it will help foster a much stronger business which will ultimately lead salaries back up again, even with various constraints.
I find MLB owners to be a pretty odious bunch, but I think we need to look out for them and ensure them some financial stability, because the game they run is very dear to a lot of people.

Monday, August 20, 2007

Can You Feel It? - How does one pitcher affect the other?

Baseball games frequently develop a “feel.” A slugfest feels much different to watch than does a pitching duel. If we’ve watched enough baseball games, we feel like we can sense the type of game we’re watching while it’s in progress and get a general sense of where it’s going to go.

Is this a very subtle sense that a baseball fan can develop, or is it just an illusion? Do we just think a given game has a given familiar feel, when in reality it’s just a randomly ordered set of random events?

Statheads will typically call this an illusion. The events of a baseball game are overwhelmingly unaffected by one another. This is a necessary and fairly accurate assumption to make. If we say each event is independent, then each event is suitable for analysis, as it is not all tied up in the context of its game and season.

If each event is independent, games can have no feel. Or at least, the feel is only experienced by the viewer and is not actually part of the game.

To begin to investigate this, I looked at a type of game that most certainly has a feel: a no-hitter. In many of the no-hitters I know about, the winning team (the team not being no-hit) also had a poor offensive showing. That is to say, while its pitcher was dominating the opposition and not allowing hits, the team’s offense was also sputtering. This would be evidence of a feel.

Since 1957 (an arbitrary year, dictated by available data), 128 games have completed 9 innings with one team not accumulating any hits (some got hits in extra innings). In those games, the other team (the one getting hits) averaged a paltry 3.9688 runs per game. Over that span of time, Major League teams averaged 4.3849 r/g. So, in those no-hit games, the other team’s offense was suppressed by 9.4912%.

Though that certainly suggests that no-hitters have a feel that spreads to both offenses, the 128 game sample size is too small to be certain. Let’s take a step back from the rare no-hitter and look at the much more common shutout, a game of any length in which one team does not score.

To do this, I looked at data from the 1996 season through the 2006 season. According to my research, there were 26,389 regular season game played in that span, 2,573 of which were shutouts. The following is the data about the shutouts separated by season. ShoR is r/g for the winning team in the shutouts, ShoG is the number of shutouts, NormR is r/g/team in all games, and NormG is the total number of games played.


96

97

98

99

00

01

02

03

04

05

06

ShoR

4.9077

4.3886

4.5861

4.6963

4.5862

4.5286

4.6145

4.3774

4.8964

4.5423

4.6834

ShoG

195

211

244

191

203

227

275

257

251

260

259

NormR

5.0377

4.767

4.7936

5.0846

5.1423

4.7756

4.6183

4.7299

4.8138

4.5936

4.8578

NormG

2266

2266

2430

2428

2428

2429

2426

2429

2428

2430

2429

In each season except 2004, the winning team in a shutout averaged fewer runs than an average team that season. In 2000 in particular, the difference is pronounced.

Between 1996-2006, the winning team in a shutout averaged 4.6152 r/g, while teams averaged 4.8368 r/g overall. That means that in this rather large sample size, the pitching staff shutting the opponent out got 4.5821% less support from its team’s offense than it would have expected.

The 2,573 shutouts provide a little over ½ a season’s worth of data (a current MLB season has 2430 games, but the shutouts were only providing data for one of the two teams). The 4.8368 r/g overall is extremely offensive, evidence of the era of offense that sandwiched the millennium, due to steroids, smaller parks, smaller strike zones or whatever. The 4.6152 r/g in the shutouts is much more moderate, though it is still offensive in a larger historical context.

Is this evidence of a game’s feel?

It is clear that suppressed offense on one side indicates a likelihood of suppressed offense on the other side. “Why,” however, is still unclear. Undeniably, some of it is due to a shared environment. A shutout is more likely to occur in Networks Associates Coliseum in Oakland with the wind blowing in than in an average environment. The difficult hitting environment that is helping one pitcher toss a shutout is also holding back his team’s offense. Or perhaps, the umpire has a large strike zone, causing the same effect as the difficult ballpark.

On the other hand, there is reason to think these games should snowball into blowouts. If a team is carrying a lead into the later innings, as a team throwing a shutout almost always will be, their last few at-bats will always come against their opponent’s middle relief, the weak spot of a team’s pitching staff. If events in the game are truly unrelated, we would then be more likely to see a 2-0 lead turn into a 4-0 lead, a 5-0 lead to turn into an 8-0 lead, and a 12-0 lead to balloon to a 16-0 lead. In a typical game, on the other hand, a team has less than a 50% chance of being ahead late, so thus less than a 50% chance of getting to bat against the weak pitching. From this point of view, we would expect runs to be held down more effectively in the non-shutouts, but this is not the case.

I think it is safe to say that games undoubtedly develop a feel. I did the same type of analysis for instances when a team scores 10 or more runs in a game (from 1996 to 2006). The opponents of a team that scored 10+ runs averaged 5.2618 r/g, an 8.7865% increase from the expected 4.8368 r/g overall.

What we cannot know (or at least, what I can’t tell you) is how much of that feel is created by the shared suppressive environment and how much is created by the intangible factors we might suspect. I do think, though, that there is some extent to which an opposing pitching staff will raise its game to try to meet the challenge set by a dominating opposing pitcher. Also, it is very possible that a team’s offense relaxes a little once it gets a lead and sees that its pitcher is dominating. On the other hand, when a pitcher is given a big lead by his team, he may try to throw lots of strikes, surrendering runs in the hopes of avoiding walks and big innings. Or perhaps, he just relaxes too much when spotted a lead.

Let’s look at one last thing. We know that a team in a nondescript game (from 1996-2006) averaged 4.8368 r/g. Over that span, a team on the right end of a shutout averaged 4.6152 r/g. Since 1957, a team whose pitchers gave up no hits through 9 innings averaged 4.3849 r/g. The more extreme the lack of offense on one side becomes, the less the other side scores.

So what about perfect games? Nineteen times in history has a pitcher completed 9 innings without allowing a baserunner. In that set, the team not being completely shut down has scored just 2.5789 r/g. The sample size is so small that this number is basically meaningless, but it still makes you think…

Sunday, August 19, 2007

Excitement Factor takes on the Playoffs

I thought it would be interesting to apply the principles of the Excitement Factor to playoff series to see how exciting a series was as a whole. The way to do this is not to see how exciting each individual game was and sum up the totals, but to track the probability of a given team winning the whole series throughout all the action.

The first set of things to be determined was the probabilities of winning the series after each game. So, if you’re up 2-1 in games, what are your chances of winning the whole thing?

Assuming that each team has a 50% chance of winning each game (a fair simplification to make), this part is fairly simple with some statistical tact. For an example, let’s determine the chances for a team up 2-0 in the series. (For this next part, “W” means “win” and “L” means “loss” and order matters.) Up 2-0, here’s how you can win the series: WW; WLW, LWW; LLWW, WLLW, LWLW; LLLWW, LLWLW, LWLLW, WLLLW. There’s one way to win in 4 games and you have a (1/2)2 chance of doing it, so 1*1/4 = .25; there are 2 ways win in 5 games and you have a (1/2)3 chance of doing either one of them, so 2*1/8 = .25. If you complete the rest of them in this fashion, you’ll find that, with a 2-0 series lead, your chances of prevailing are .8125. The following table shows the probabilities for every single situation in a 7-game series.

This is a good start, but integrating these series win expectancies in to the games’ play-by-play account can be difficult. Again, I think this is most easily explained by example. Say, once again, you’re up 2-0. At the time of the first pitch we know your chances of winning the series are .8125. Game 3 is going to lead you to one of two situations: leading 3-0 or leading 2-1. If you lead 3-0, your chances jump to .9375, if you lead 2-1, they fall to .6875. So, to find your probability of winning the series at a moment in Game 3, you multiply your chances of winning Game 3 by .9375 and add to that your chances of losing Game 3 multiplied by .6875. This covers all the possible ways you can win the series, the set that includes winning Game 3 and the set in which you lose it. For the opening pitch of Game 3 (when the team’s chance of winning is .5), you could just trust me that your chances of winning are .8125 or you can check for yourself: .5*(.9375)+(1-.5)*(.6875) = .46875+.34375 = .8125. This can of course be done as the game situation changes and the probabilities of winning the given game and the series as a whole move up and down. Then, as with the original excitement factor, it’s just a matter of summing up the absolute value of every change that the series factor (excitement factor deluxe, from now on) undergoes.

Keep in mind, this deluxe version follows the same principles as the original excitement factor. Just as scoring lots of runs was important in having a high excitement factor, playing lots of games is important in the excitement factor deluxe because it allows for more mobility. The nature of a playoff series is also nice in that the more games the teams play the closer the series is, since blowouts end quickly. In the original excitement factor, action in the late innings was important; in the excitement factor deluxe, the later games are more important. This has a very easy mathematical explanation that agrees with the viewing experience. Let’s consider a leadoff single in the bottom of the 6th of a tie game. This raises the home team’s win expectancy from .577 to .627. In the original excitement factor, that’s worth .05. Moving to the deluxe, that same event in Game 1 would shift the probability of winning the series from .577(.6563)+(1-.577)(1-.6563) = .5241 to .627(.6563)+(1-.627)(1-.6563) = .5397, a shift of .0156. In Game 7, you don’t have to multiply the probability by all that mumbo jumbo to account for the rest of the games in the series; if you win the game you win, if not, you lose. So, in Game 7, that single would shift the probability from .577 to .627, a .05 boost. The possibility of future games dilutes the importance of the current one, so as fewer games remain, the importance grows.

The following table shows the excitement factors deluxe for the World Series from 2002 through 2006. To remind you, 2002 went the maximum 7 games, 2003 went 6, 04 and 05 were 4-game sweeps, and 06 took 5 games. As you can see, the only instance where the EFD isn’t in line with the number of games is 2005, but the White Sox and Astros played some unbelievable games in that series, though the former wound up winning all of them.

This of course isn’t a large enough sample size to draw conclusions from, but there’s something evident that we would expect to be true and I think it’s worth pointing out. The correlation between games and EFD is not linear. The 4-game 04 Series was 2.639, the 6-game 03 Series was 6.448, and the 7-game 02 Series was 9.368. As we said, the games are not of equal importance. Playing deeper into the Series not only adds more games, but it adds games that are more important/exciting.

So how about those classic ALCSs between New York and Boston, semifinal matchups that certainly resound more clearly than their ensuing finals? Let’s take a look at how exciting those really were. The EFDfor 2003 (Aaron Boone's series) was 10.597. For 2004 (the Red Sox's historic comeback) it was 6.859.

The 2003 ALCS pretty much dwarfs the one from 2004. Of course, 2004 was the one where the Red Sox made the greatest playoff series comeback in baseball history, but that wasn’t enough. One truth we found in the original excitement factor is that, within a game, one huge comeback doesn’t compare very well to multiple smaller comebacks. Evidently, this holds true for series. Amazingly, in 2004, the Red Sox won a series in which they had, at one point, a 1.9% chance of prevailing. However, that series only saw the Red Sox fall really far, then rise really high really quickly. That is not as exciting as things can get. In 2003, the ALCS went 1-0 Red Sox, 2-1 Yankees, 2-2, 3-2 Yankees, 3-3, and the Yankees ultimately won 4-3.

So, the excitement factor has met its first real obstacle, and it has conquered it.

Excitement Factor

On Monday, September 18th, the Dodgers and Padres played one of the most exciting games in recent memory. The Dodgers twice overcame 4-run deficits, including an almost humorously ridiculous run of back-to-back-to-back-to-back home runs to lead off the bottom of the 9th to tie the game. Though the Padres scored a run in the 10th, the Dodgers again made hearts leap in the bottom of the inning with a two-run, walk-off, come-from-behind home run.
Clearly, that game was Bayer-worthy. Some have taken to calling it the game of the millennium, some going as far as to call it one of the best games in baseball history. The question is, how exciting was the game? Excitement is a strictly emotional response to the action on the field and thus is very hard to evaluate numerically. However, there are some subjective, emotional facts we know to be true. Excitement is generated when the outcome of the game is in doubt. Even more so, a game is exciting when an outcome seems apparent and then events take place to completely alter the complexion of the contest.
Fortunately, we are able to measure and track the probability of a given outcome. Win expectancy percentages are available for every potential game situation (any combination of score, inning, outs, and base runners). This allows us to track the chances of a team winning throughout the entire game.

Here, we see a graph in which the win expectancy is shown as a function of the event number. Any occurrence that moves a base runner or makes an out is an event. This mostly consists of plate appearances, but includes wild pitches and stolen base attempts as well.
The graph, though it looks nice and curvy, is actually made up of a good deal of straight lines. Obviously, the sum of these lines is equal to about +/-.5 every time, as a team enters with about a 50% chance of winning and finishes with chances of either 0% or 100%. However, an interesting thing happens when instead of just adding up the lines, we add up the absolute value of each line. That is to say, when a team increases its chances of winning by 10%, that is worth .1, and when their chances decrease by 10%, that is also worth .1. This accurately allows us to see how much the probability of an outcome changed over the course of the game, the essence of excitement.
The above graph is the progression of the Brewers’ chances during their game with the Dodgers on September 4th. That game seemed to me to be pretty standard. The Dodgers scored a run in the top of the 1st, with the Brewers responding in the 2nd and taking a 4-1 lead in the 5th. The Dodgers rallied to within one, but Milwaukee pulled away to a 6-3 win. By taking the absolute value of each line and adding them up, this game has an Excitement value of 2.5.
On September 19th, the Twins took an early 6-0 lead on the Red Sox and though the lead was cut in half, the Twins coasted to an easy 7-3 victory. Though the final score doesn’t suggest a blowout, in many ways this game was, as the outcome was never really put in doubt. Below is the graph of the Twins’ chances throughout the game.

This pounding provided an understandable low Excitement rating of 2.08.
So how good was the Dodgers-Padres game? Well first, admire the below graph of the Dodgers’ evolving win expectancy.


What we see are large dips and spikes as the teams made runs at each other, one taking a commanding position, only to watch as the other turned what looked like imminent defeat into a contest. This game had a staggering Excitement level of 8.56.
A flaw with this system is apparent by how it analyzes the Dodgers’ 9th. The game would have rated exactly the same if instead of the first three homers, the Dodgers had walked three times. The oversight here is that home runs are intrinsically exciting. I believe the system accurately suggests that in terms of putting the game in doubt, a walk is as good as a homer, but watching those balls fly into the night successively was just so special and exhilarating and Excitement by Win Expectancy can’t capture that.
Now, until a greater number of games is given an Excitement rating, this number has little meaning, as there’s no real frame of reference (there aren’t even units). We do know that it’s not unusual for a game to be rated between 2 and 2.5, so the 8.56 rating is quite impressive, despite our relative lack of understanding of how it really stacks up.
However, I found one thing particularly interesting during this study. The game between the White Sox and Cardinals on June 22nd saw 5 hits and 1 run, coming on a 7th-inning Jim Thome homer, and can certainly be classified as a pitching duel. Conventional opinion will tell you that a pitching duel is just as exciting as a slugfest. A good subjective point can be made to support this case, as a pitching duel keeps the run total low and thus the score very close throughout the course of the game. Below is the graph of the Cardinals’ chances during that game.

This game ranked lower than any of the other three discussed, with an Excitement rating of 1.98, despite the fact that it was tied into the late innings and never put out of reach. A simple conclusion can be drawn from this: runs are exciting. Though the first six innings of this game set the stage for an exciting conclusion, they in themselves provided no excitement. This all makes sense, though, as we already know that excitement is generated when the course of a game shifts from its apparent outcome. When runs are not scoring, nothing is changing.
This system can help us to understand why baseball and football dominate the American sports landscape. In both sports, scoring happens fairly regularly, but is not excessive. An early touchdown in football or a pair of early runs in baseball put a team at an advantage and can be made to hold up, but by no means put the game away. In basketball, the baskets at the moment they are scored are basically meaningless because they account for such a small portion of the final score. In hockey (or soccer for that matter) goals come so rarely that the excitement (though a good save is exciting in its own way) comes infrequently, so when it does come, it greatly shifts the win expectancy. In “goal sports”, it’s very difficult to get the back and forth that create uber-excitement like we witnessed in LA this September.
(All graphs taken from fangraphs.com)