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October 7, 2006 12:00 am

Prospectus Today: Division Series, Day Four

0

Joe Sheehan

The A's won a Division Series, and they did it their way. The Tigers are one win away from joining them in an ALCS matchup no one predicted.

\nMathematically, leverage is based on the win expectancy work done by Keith Woolner in BP 2005, and is defined as the change in the probability of winning the game from scoring (or allowing) one additional run in the current game situation divided by the change in probability from scoring\n(or allowing) one run at the start of the game.'; xxxpxxxxx1160276734_18 = 'Adjusted Pitcher Wins. Thorn and Palmers method for calculating a starters value in wins. Included for comparison with SNVA. APW values here calculated using runs instead of earned runs.'; xxxpxxxxx1160276734_19 = 'Support Neutral Lineup-adjusted Value Added (SNVA adjusted for the MLVr of batters faced) per game pitched.'; xxxpxxxxx1160276734_20 = 'The number of double play opportunities (defined as less than two outs with runner(s) on first, first and second, or first second and third).'; xxxpxxxxx1160276734_21 = 'The percentage of double play opportunities turned into actual double plays by a pitcher or hitter.'; xxxpxxxxx1160276734_22 = 'Winning percentage. For teams, Win% is determined by dividing wins by games played. For pitchers, Win% is determined by dividing wins by total decisions. '; xxxpxxxxx1160276734_23 = 'Expected winning percentage for the pitcher, based on how often\na pitcher with the same innings pitched and runs allowed in each individual\ngame earned a win or loss historically in the modern era (1972-present).'; xxxpxxxxx1160276734_24 = 'Attrition Rate is the percent chance that a hitters plate appearances or a pitchers opposing batters faced will decrease by at least 50% relative to his Baseline playing time forecast. Although it is generally a good indicator of the risk of injury, Attrition Rate will also capture seasons in which his playing time decreases due to poor performance or managerial decisions. '; xxxpxxxxx1160276734_25 = 'Batting average (hitters) or batting average allowed (pitchers).'; xxxpxxxxx1160276734_26 = 'Average number of pitches per start.'; xxxpxxxxx1160276734_27 = 'Average Pitcher Abuse Points per game started.'; xxxpxxxxx1160276734_28 = 'Singles or singles allowed.'; xxxpxxxxx1160276734_29 = 'Batting average; hits divided by at-bats.'; xxxpxxxxx1160276734_30 = 'Percentage of pitches thrown for balls.'; xxxpxxxxx1160276734_31 = 'The Baseline forecast, although it does not appear here, is a crucial intermediate step in creating a players forecast. The Baseline developed based on the players previous three seasons of performance. Both major league and (translated) minor league performances are considered.

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October 6, 2006 12:00 am

Prospectus Today: Division Series, Day Three

0

Joe Sheehan

The Yankees continued their run through the ... hey, not so fast! In San Diego, the Cardinals continued to make a statement about the importance of home-field advantage, while in New York the Mets were the one team to keep order in the first two games.

\nMathematically, leverage is based on the win expectancy work done by Keith Woolner in BP 2005, and is defined as the change in the probability of winning the game from scoring (or allowing) one additional run in the current game situation divided by the change in probability from scoring\n(or allowing) one run at the start of the game.'; xxxpxxxxx1160157644_18 = 'Adjusted Pitcher Wins. Thorn and Palmers method for calculating a starters value in wins. Included for comparison with SNVA. APW values here calculated using runs instead of earned runs.'; xxxpxxxxx1160157644_19 = 'Support Neutral Lineup-adjusted Value Added (SNVA adjusted for the MLVr of batters faced) per game pitched.'; xxxpxxxxx1160157644_20 = 'The number of double play opportunities (defined as less than two outs with runner(s) on first, first and second, or first second and third).'; xxxpxxxxx1160157644_21 = 'The percentage of double play opportunities turned into actual double plays by a pitcher or hitter.'; xxxpxxxxx1160157644_22 = 'Winning percentage. For teams, Win% is determined by dividing wins by games played. For pitchers, Win% is determined by dividing wins by total decisions. '; xxxpxxxxx1160157644_23 = 'Expected winning percentage for the pitcher, based on how often\na pitcher with the same innings pitched and runs allowed in each individual\ngame earned a win or loss historically in the modern era (1972-present).'; xxxpxxxxx1160157644_24 = 'Attrition Rate is the percent chance that a hitters plate appearances or a pitchers opposing batters faced will decrease by at least 50% relative to his Baseline playing time forecast. Although it is generally a good indicator of the risk of injury, Attrition Rate will also capture seasons in which his playing time decreases due to poor performance or managerial decisions. '; xxxpxxxxx1160157644_25 = 'Batting average (hitters) or batting average allowed (pitchers).'; xxxpxxxxx1160157644_26 = 'Average number of pitches per start.'; xxxpxxxxx1160157644_27 = 'Average Pitcher Abuse Points per game started.'; xxxpxxxxx1160157644_28 = 'Singles or singles allowed.'; xxxpxxxxx1160157644_29 = 'Batting average; hits divided by at-bats.'; xxxpxxxxx1160157644_30 = 'Percentage of pitches thrown for balls.'; xxxpxxxxx1160157644_31 = 'The Baseline forecast, although it does not appear here, is a crucial intermediate step in creating a players forecast. The Baseline developed based on the players previous three seasons of performance. Both major league and (translated) minor league performances are considered.

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Jim cleans up some old business, ponders the all-time greats at second base, and tries to avoid throwing things at the TV set.

\nMathematically, leverage is based on the win expectancy work done by Keith Woolner in BP 2005, and is defined as the change in the probability of winning the game from scoring (or allowing) one additional run in the current game situation divided by the change in probability from scoring\n(or allowing) one run at the start of the game.'; xxxpxxxxx1160158525_18 = 'Adjusted Pitcher Wins. Thorn and Palmers method for calculating a starters value in wins. Included for comparison with SNVA. APW values here calculated using runs instead of earned runs.'; xxxpxxxxx1160158525_19 = 'Support Neutral Lineup-adjusted Value Added (SNVA adjusted for the MLVr of batters faced) per game pitched.'; xxxpxxxxx1160158525_20 = 'The number of double play opportunities (defined as less than two outs with runner(s) on first, first and second, or first second and third).'; xxxpxxxxx1160158525_21 = 'The percentage of double play opportunities turned into actual double plays by a pitcher or hitter.'; xxxpxxxxx1160158525_22 = 'Winning percentage. For teams, Win% is determined by dividing wins by games played. For pitchers, Win% is determined by dividing wins by total decisions. '; xxxpxxxxx1160158525_23 = 'Expected winning percentage for the pitcher, based on how often\na pitcher with the same innings pitched and runs allowed in each individual\ngame earned a win or loss historically in the modern era (1972-present).'; xxxpxxxxx1160158525_24 = 'Attrition Rate is the percent chance that a hitters plate appearances or a pitchers opposing batters faced will decrease by at least 50% relative to his Baseline playing time forecast. Although it is generally a good indicator of the risk of injury, Attrition Rate will also capture seasons in which his playing time decreases due to poor performance or managerial decisions. '; xxxpxxxxx1160158525_25 = 'Batting average (hitters) or batting average allowed (pitchers).'; xxxpxxxxx1160158525_26 = 'Average number of pitches per start.'; xxxpxxxxx1160158525_27 = 'Average Pitcher Abuse Points per game started.'; xxxpxxxxx1160158525_28 = 'Singles or singles allowed.'; xxxpxxxxx1160158525_29 = 'Batting average; hits divided by at-bats.'; xxxpxxxxx1160158525_30 = 'Percentage of pitches thrown for balls.'; xxxpxxxxx1160158525_31 = 'The Baseline forecast, although it does not appear here, is a crucial intermediate step in creating a players forecast. The Baseline developed based on the players previous three seasons of performance. Both major league and (translated) minor league performances are considered.

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October 5, 2006 12:00 am

Prospectus Today: Division Series, Day Two

0

Joe Sheehan

The Play is the talk of the water coolers, but plenty of other things happened on an abbreviated second day.

\nMathematically, leverage is based on the win expectancy work done by Keith Woolner in BP 2005, and is defined as the change in the probability of winning the game from scoring (or allowing) one additional run in the current game situation divided by the change in probability from scoring\n(or allowing) one run at the start of the game.'; xxxpxxxxx1160071649_18 = 'Adjusted Pitcher Wins. Thorn and Palmers method for calculating a starters value in wins. Included for comparison with SNVA. APW values here calculated using runs instead of earned runs.'; xxxpxxxxx1160071649_19 = 'Support Neutral Lineup-adjusted Value Added (SNVA adjusted for the MLVr of batters faced) per game pitched.'; xxxpxxxxx1160071649_20 = 'The number of double play opportunities (defined as less than two outs with runner(s) on first, first and second, or first second and third).'; xxxpxxxxx1160071649_21 = 'The percentage of double play opportunities turned into actual double plays by a pitcher or hitter.'; xxxpxxxxx1160071649_22 = 'Winning percentage. For teams, Win% is determined by dividing wins by games played. For pitchers, Win% is determined by dividing wins by total decisions. '; xxxpxxxxx1160071649_23 = 'Expected winning percentage for the pitcher, based on how often\na pitcher with the same innings pitched and runs allowed in each individual\ngame earned a win or loss historically in the modern era (1972-present).'; xxxpxxxxx1160071649_24 = 'Attrition Rate is the percent chance that a hitters plate appearances or a pitchers opposing batters faced will decrease by at least 50% relative to his Baseline playing time forecast. Although it is generally a good indicator of the risk of injury, Attrition Rate will also capture seasons in which his playing time decreases due to poor performance or managerial decisions. '; xxxpxxxxx1160071649_25 = 'Batting average (hitters) or batting average allowed (pitchers).'; xxxpxxxxx1160071649_26 = 'Average number of pitches per start.'; xxxpxxxxx1160071649_27 = 'Average Pitcher Abuse Points per game started.'; xxxpxxxxx1160071649_28 = 'Singles or singles allowed.'; xxxpxxxxx1160071649_29 = 'Batting average; hits divided by at-bats.'; xxxpxxxxx1160071649_30 = 'Percentage of pitches thrown for balls.'; xxxpxxxxx1160071649_31 = 'The Baseline forecast, although it does not appear here, is a crucial intermediate step in creating a players forecast. The Baseline developed based on the players previous three seasons of performance. Both major league and (translated) minor league performances are considered.

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The Player Cards are back! First, let me emphasize that these player cards are an ongoing project. I fully expect to be able to make future revisions to the cards themselves and the glossary without having to take everything down again. Some of these changes--like a full set of translated statistics for every player, to go with their actual statistics -are already in the works. Others -like extensions to the glossary- will follow the questions from readers.

The Player Cards are back!

First, let me emphasize that these player cards are an ongoing project. I fully expect to be able to make future revisions to the cards themselves and the glossary without having to take everything down again. Some of these changes--like a full set of translated statistics for every player, to go with their actual statistics­-are already in the works. Others­-like extensions to the glossary-­will follow the questions from readers.

I'll leave most of the statistical descriptions to the glossary, and spend my time here talking about some of the general principles behind the numbers. Please, please, please, read the glossary. I know there are a lot of blanks to fill in yet, but the basics are covered there.

The key statistic that everything builds toward is called WARP--Wins Above Replacement Player. The Replacement Player I'm using for my comparison is at replacement level across the board--batting, pitching, and fielding. A replacement level hitter is one who would hit for a .230 equivalent average; that implies a winning percentage, other things being equal, of about .350 (i.e., a team with average pitching and fielding that hit for a .230 EQA would go 57-105). A replacement level pitcher is also defined to have a winning percentage of .350; given a standard ERA of 4.50, that would mean a replacement level ERA of 6.11. The combination of replacement level hitting and pitching gives you a winning percentage of .227, or 37-125... not too different from the 1962 Mets. However, this team is also replacement level in the field, a team full of fielders like Dean Palmer and Greg Luzinski and Steve Sax and Jose Offerman. The idea is that replacement level fielding was about equal to the worst regular in the league, maybe a little less. That's going to cost the team as much as the pitching does, so our fully replacement level team is only going to be worth about a .137 percentage (22-140). The closest thing in history to a replacement level team was the 1899 Cleveland Spiders, who went 20-134, a .130 winning percentage.

When a player is rated for WARP, each component is rated independently. The hitting component of WARP is always found by comparing the player to one with a .230 EQA, regardless of what position he plays (yes, even pitchers). A batter is a batter--there is no position at the plate. Pitchers are rated by comparing them to an adjusted ERA of 6.11 (well, not exactly; the relative pitching/fielding shares of defense will modify that. The pitcher/fielding combination has a replacement ERA value of 7.36). The closest thing to a "position adjustment" in the WARP system comes from the defensive data, not the offensive skills of the guys who play there. An average player at a skill position is considered to be farther above replacement than an average player at a side positon. How much depends on the number of plays the position is called upon to make. To look at the Spiders again, they had a team EqA of .229; 5 runs below replacement level. Their pitching rated 27 runs above replacement; their fielding was just 13 above (keep in mind that these batting, pitching, and fielding numbers would be 189, 158, and 210 runs below average). The ratings for the team come to just 3 WARP, which does sort of imply that I would have only expected them to win 24 games.

So two things to be aware of--the replacement level is set so low as to be almost zero, and the fielding input is pretty high. That brings me to another distinction you'll see on the cards, the difference between season-adjusted statistics and alltime-adjusted statistics. Pitching and fielding statistics do not project across time as readily as offensive statistics, because the balance between the two has changed, dramatically, over time. Fielding has never been less important to the outcome of the game than it is today, what with the very high (historically speaking) numbers of strikeouts, walks, and home runs. Go back to the 1880s, though, and not only is virtually every ball in play, but the difference between the best and worst fielders was much wider than it is now. I have players rated at being 50 runs above average in the field in a 110-game season--a rate that would be absolutely impossible to achieve today. If I simply converted those numbers to today's standards (by standard deviations, say), that might convert to 20 runs above average--and I just converted 30 runs the man truly provided in his time out of existence. That isn't entirely right. So the season side doesn't convert the numbers, but lets them stand as they were within the season. The alltime side does convert them.

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October 12, 2000 12:00 am

Call It In The Air!

0

Dave Pease

\nMathematically, leverage is based on the win expectancy work done by Keith Woolner in BP 2005, and is defined as the change in the probability of winning the game from scoring (or allowing) one additional run in the current game situation divided by the change in probability from scoring\n(or allowing) one run at the start of the game.'; xxxpxxxxx1160184488_18 = 'Adjusted Pitcher Wins. Thorn and Palmers method for calculating a starters value in wins. Included for comparison with SNVA. APW values here calculated using runs instead of earned runs.'; xxxpxxxxx1160184488_19 = 'Support Neutral Lineup-adjusted Value Added (SNVA adjusted for the MLVr of batters faced) per game pitched.'; xxxpxxxxx1160184488_20 = 'The number of double play opportunities (defined as less than two outs with runner(s) on first, first and second, or first second and third).'; xxxpxxxxx1160184488_21 = 'The percentage of double play opportunities turned into actual double plays by a pitcher or hitter.'; xxxpxxxxx1160184488_22 = 'Winning percentage. For teams, Win% is determined by dividing wins by games played. For pitchers, Win% is determined by dividing wins by total decisions. '; xxxpxxxxx1160184488_23 = 'Expected winning percentage for the pitcher, based on how often\na pitcher with the same innings pitched and runs allowed in each individual\ngame earned a win or loss historically in the modern era (1972-present).'; xxxpxxxxx1160184488_24 = 'Attrition Rate is the percent chance that a hitters plate appearances or a pitchers opposing batters faced will decrease by at least 50% relative to his Baseline playing time forecast. Although it is generally a good indicator of the risk of injury, Attrition Rate will also capture seasons in which his playing time decreases due to poor performance or managerial decisions. '; xxxpxxxxx1160184488_25 = 'Batting average (hitters) or batting average allowed (pitchers).'; xxxpxxxxx1160184488_26 = 'Average number of pitches per start.'; xxxpxxxxx1160184488_27 = 'Average Pitcher Abuse Points per game started.'; xxxpxxxxx1160184488_28 = 'Singles or singles allowed.'; xxxpxxxxx1160184488_29 = 'Batting average; hits divided by at-bats.'; xxxpxxxxx1160184488_30 = 'Percentage of pitches thrown for balls.'; xxxpxxxxx1160184488_31 = 'The Baseline forecast, although it does not appear here, is a crucial intermediate step in creating a players forecast. The Baseline developed based on the players previous three seasons of performance. Both major league and (translated) minor league performances are considered.

The Baseline forecast is also significant in that it attempts to remove luck from a forecast line. For example, a player who hit .310, but with a poor batting eye and unimpressive speed indicators, is probably not really a .310 hitter. Its more likely that hes a .290 hitter who had a few balls bounce his way, and the Baseline attempts to correct for this.

\nSimilarly, a pitcher with an unusually low EqHR9 rate, but a high flyball rate, is likely to have achieved the low EqHR9 partly as a result of luck. In addition, the Baseline corrects for large disparities between a pitchers ERA and his PERA, and an unusually high or low hit rate on balls in play, which are highly subject to luck. '; xxxpxxxxx1160184488_32 = 'Approximate number of batting outs made while playing this position.'; xxxpxxxxx1160184488_33 = 'Batting average; hits divided by at-bats. In PECOTA, Batting Average is one of five primary production metrics used in identifying a hitters comparables. It is defined as H/AB. '; xxxpxxxxx1160184488_34 = 'Bases on Balls, or bases on balls allowed.'; xxxpxxxxx1160184488_35 = 'Bases on balls allowed per 9 innings pitched.'; xxxpxxxxx1160184488_36 = 'Batters faced pitching.'; xxxpxxxxx1160184488_37 = 'Balks. Not recorded 1876-1880.'; xxxpxxxxx1160184488_38 = 'Batting Runs Above Replacement. The number of runs better than a hitter with a .230 EQA and the same number of outs; EQR - 5 * OUT * .230^2.5.'; xxxpxxxxx1160184488_39 = 'Batting runs above a replacement at the same position. A replacement position player is one with an EQA equal to (230/260) times the average EqA for that position.'; xxxpxxxxx1160184488_40 = 'Breakout Rate is the percent chance that a hitters EqR/27 or a pitchers EqERA will improve by at least 20% relative to the weighted average of his EqR/27 in his three previous seasons of performance. High breakout rates are indicative of upside risk.

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