ATL Player and Ballpark Usage Info

There are no league restrictions or regulations on normal player usage in the ATL. Every player is a full-time player. That is the prime rule.

There are no league constraints on how you, as Owner and General Manager, develop your roster. You can have on your roster any group of 35 players that you can draft, sign or trade for. However, having a well-rounded roster is part of winning a pennant. It will be best to have a roster strategy that includes at least 3 players rated to play catcher, shortstop, second base and centerfield. These are the most important positions on the field, and players who can play these positions well are at a premium. It is also a good strategy to have some balance on the pitching staff between right-handers and left-handers. But the bottom line is that the league does not force any requirement on you. You are free to experiment.

There are no league constraints on how you, as Field Manager, use your players. The players can be played at any position, but they will perform best in the role they are set up for. The game will handle players used out of position by penalizing them appropriately. It is all within the game mechanics, and only hinted at by the DMB Help files, so experience is the best teacher in this regard. The best strategy is to be prepared, and only use players in the role they are meant to be used in. For the specifics of what the DMB Help file says about this topic, read here:

• You can use a player at a defensive position for which he is not rated, but his performance will suffer. How much? It depends.
• Players can make a relatively painless transition to an easier position that is similar to one they're already rated for. The penalties are much greater for moving to a very different position that is also more difficult to play.
• For example, a CF can play LF or RF without suffering much at all. Both positions are similar and easier than the one he's rated for. A LF or RF moving to CF has a more difficult time because there's more ground to cover. Similarly, a move from SS to 2B won't cost you too much, while a move from 2B to SS will hurt more. And the moves that will hurt the most are (a) from any position to catcher, (b) a catcher moving to any position except 1B, and (c) a 1B moving to CF or another infield position.
• How will these penalties show up? In lots of ways. More balls in their zones will go for hits. They'll make more errors. Guys without outfielder throwing or catcher throwing ratings will be easier to run on. Unrated catchers will have more passed balls. Unrated middle infielders won't start as many double plays on balls hit to them, and they won't turn two as often when they're the pivot man on the play. Pitchers without hold ratings will be easier to run on.
• You might ask why we apply penalties even when a player is moving to a less difficult position. Couldn't a top-rated SS play 2B as well or better than the average 2B? In the many years that we've been assigning fielding ratings, we've seen a lot of players get higher ratings when they make the transition from a harder position to an easier one (especially SS -> 2B, 3B -> 1B, and CF -> LF), but we've also seen plenty of cases where the player needed some time to learn how to play the new position.
• Every position requires mastery of a different set of skills. A CF moving to RF needs to learn how to play the caroms on balls hit down in the corner. A 3B needs great reflexes to handle the hot smashes that come his way, and that might not be the strong suit of a middle infielder moving to 3B. A SS moving to 2B must learn how to make the pivot with his back to the runner.
• If our out-of-position adjustments assumed that every player could instantly adapt to a new position, even an easier one, we think it would create too many opportunities for managers to abuse the game by moving players around in ways that real-life managers would never get away with. So the game imposes penalties of varying degrees on all out-of-position players.
• real-life managers sometimes ask position players to throw an inning on the mound to save the bullpen in a blowout, and sometimes these players manage to retire a few hitters. Overall, they don't do very well, and you'll find that the same is true if you try this in DMB.

So we see that although we can put any player anywhere on the diamond we want, we will get better results if we do not force players into situations they did not usually find themselves.

What is true for the real baseball teams is even more so here where every player is a star.  Even the lesser players in the ATL were at least franchise stars when they played the game. Every ATL game is an All-Star game. It will take a good roster strategy and a good managing strategy to have a good season.  Having good players in the lineup is not enough -- every team in this league has good players in the lineup.

Injuries are the bane of every team's season, and injuries are the great unknowable future catastrophe awaiting every team in every next game. Nobody can predict when an injury will strike, or how long a player will go without an injury.  Seasons and careers have been unmade because of injury. Injuries have shaped many a player's career.  That is real life. Here in the ATL we use the Random Injury setting to simulate just that black void of undetermined injury potential. None of us knows which player will get struck down by a season-crushing injury. One thing we do have the luxury of, is that no injury will affect a player's career in any way except to shorten the amount of games the player would otherwise have played.

Managing injuries is your task. You must decide whether to put a player on the Disabled List or carry that player on a roster spot even though the player cannot play. Disabling a player may lengthen the time a player is out of action because league regulations state that Roster Changes can only be made between series. That means you may not be able to Activate a player immediately after the injury is over -- you have to wait until the current series of  games is over and put in the Activate order for between-series. Since we play 4-day series, the time a player is out could be lengthened by up to 4 days, or a multiple of 4 days if you forget to Activate the player on time. You can consider the extra time on the Disabled List as special injury rehabilitation time. You cannot have a standing order for the Commissioner to activate a player as soon as possible, it is your responsibility as Owner, General Manager and Field Manager to watch over every aspect of your team and its players.

Players traditionally have certain roles, and the players in this set are depicted in the roles they played for the time periods depicted by the player set. However, you have complete control over this aspect of your team as well. You can choose to change the role of any player on your roster. Most commonly we will see starting pitchers used as relief pitchers simply because there are not enough good relief pitchers in this player set.  Or put another way, there are an abundance of good starting pitchers in this player set, more so than relief pitchers. Many teams have more than enough starters and are short on relievers, and so the roles shall be changed. For pitchers who do have a relief rating there will be no penalties for playing out of position -- because they are rated at the position of relief pitcher. For those pitchers without a relief rating, or for the opposite -- those relievers without a rating as starting pitcher, the normal penalties for playing out of position will apply.

How do you change their roles?  Simply use the Manager Profile to define the role you want a pitcher to play. There are slots for Setup Men, Closers, Mopup guys, Long Relievers, Spot Starters and your normal rotation.  Here is a good place to quote the DMB Help file about some very important settings on the pitcher pages that you have complete control over -- and will decide how the computer uses your pitchers during Autoplay games (during Netplay games you have complete and utter control over your players except for Roster Changes and Roster Mods -- which are not allowed during Netplay).

The following is very important, please read it all the way through.  At the bottom of the rotation box in the roster/manager profile section, there are 3 additional boxes. These three boxes control very powerful functions:

• Select Time mode to have the computer manager do its best to make sure that every starting pitcher and reliever gets exactly as many starts and relief appearances as they had in real life. This mode is appropriate for teams that have their real-life rosters intact, and it should NOT be used when you are playing a season with newly-drafted rosters.
• NOTE: In Time mode, the computer manager ignores your rotation. Instead, it looks at how many starts each pitcher is limited to in the playing time limits section of your profile (this is usually set to match his real-life starts) and spreads those starts evenly over the season. The pitcher with the most real-life starts will be selected on opening day even if he is not listed in the #1 slot in the rotation. The computer manager will choose starting pitchers who are not in the rotation if their games started limit is greater than zero.
• Select Strict mode to have the computer manager use your pitchers in the order they appear in the starting rotation. The computer manager will choose another starting pitcher only if a rotation starter is injured when his turn comes up (or if you are using the Spot Start Percentage rating for Spot Starters, and that percentage chance has happened).
• Select Skip to have the computer manager use your pitchers in the order they appear in the starting rotation but skip to the #1 starter when one or more off-days have left him rested enough to start before his turn. The computer manager will choose another starting pitcher only if a rotation starter is injured when his turn comes up.
• Rotation Size You can enter a number to tell the computer manager how big the starting rotation should be. Modern teams almost always use a five-man rotation. Four-man rotations were common until the 1970s, and smaller rotations were the norm a hundred years ago.
• Although the saved starting rotation is ignored in the Usage mode of Time, it is still important to set your rotation size in order to get the most out of your starting pitchers. If a pitcher made 40 starts, the rotation size must be set no higher than 4 in order for him to reach his maximum number of starts. If you set the size at 5, he won't make more than 33 starts in a 162-game season.
• The Rotation Size is also used to enforce a Strict or Skip rotation.
• Next Starter. When you are using either the Strict or Skip rotation mode, this value tells the computer manager which rotation slot is due to start the next game. You can change this if you want to juggle your rotation during a season.
• NOTE: When the computer manager selects a starting pitcher in Strict or Skip mode, it simply chooses the pitcher who is in the Next starter slot. It doesn't look at who was used in recent games, so it's up to you to make sure that the Next starter value is set appropriately if you are mixing human-managed games and computer-managed games for this team.
  

• Choose Track Starts if you wish to simulate an entire season and you want your players to match the playing time indicated in the depth chart. With this setting, the computer manager keeps track of how often each player starts at each position versus left- and right-handed pitching in your DMB games. During the season, it uses this information to adjust the starting lineups to keep everyone on a pace to accumulate the amount of playing time indicated in your depth charts.
• NOTE: If your goal is to match real-life playing time as closely as possible, we recommend that you choose None for your League Injury Rule, Yes for the Limit Bench Playing Time option. See Leagues: Rules and Options for more details on these settings.
• Choose Game by Game if you want to change the roles of your players during a season. With this setting, the computer manager takes each game at a time and randomly chooses spot starters using the spot start percentages in your depth chart.

• The Catcher Fatigue system is designed to ensure that you limit your starting catcher to about 85-90% of total playing time. It does so by monitoring usage within a moving ten-day window as the season goes along.
• If you're in a stretch where your team has no days off, your catcher will almost certainly get tired if you start him ten games in a row. Giving a catcher an off day once every ten days is sometimes enough to keep him rested, and giving him two days off will definitely keep him at full strength unless he caught a couple of long extra-inning games in that stretch.
• A catcher's workload is determined on a batters-caught basis. In a modern season, a team typically faces about 6250 batters over a 182-day schedule. That's about 344 batters per ten day period, and because we try to limit catchers to 85-90% of total playing time, you should try to keep your catchers from facing more than 300 batters in a ten day period. You can monitor catcher usage using the Team Status report and the Status page of the Player Profile window.
• If a catcher is used more than this, he will be less productive as a hitter and fielder, with the penalty being greater the further the catcher is over the limit. The penalty is very severe if you let someone catch every inning of every game, so it's not something you'd want to try on a regular basis.
• Using a catcher at another position (including designated hitter) is equivalent to giving him the day off, but you need to do this in advance. If you catch him too much and he gets tired as a result, you can't play him at another position the next game without penalizing him at the plate. But if you play him somewhere else once in a while, that will help keep him rested in the first place.

• A depth chart goes hand in hand with a saved lineup, and guides the computer manager in its use of players who are not in the starting lineup. There are four roles that you can assign to a bench player in a depth chart:
• Platoon Player. A platoon is a pair of players, one who bats left-handed and one who bats right-handed. The manager starts the left-hander against right-handed pitchers and the right-hander against left-handed pitchers. If the opposing team changes pitchers, the computer manager may substitute the platoon player to get a favorable left-right matchup.
• Defensive Replacement. If you specify a player in this role, the player will be inserted into a game in the late innings of games in which the team has a narrow lead.
• Utility Player (aka Substitute Player). You can list up to five players as utility players at each defensive position. These players are used when a starter is injured or removed for a pinch hitter or pinch runner during a game. If you want someone to be used primarily as a bench player but make occasional starts, you can indicate the percentage of games this player should start at this position.
• Pinch Hitter. You can list up to five players as pinch hitters versus left- or right-handed pitchers.
• Defensive Replacements
• The computer manager currently makes defensive replacement decisions one position at a time. That means that there's no point in trying to set up your profile to make a series of defensive shifts. For example, you cannot tell the computer manager to insert a player as a defensive replacement in center, move the starting center fielder to right, and remove the right fielder.
• Pinch hitters
• You don't have to fill the list in to make the computer manager use pinch hitters. If these lists are empty, DMB chooses pinch hitters from all available players on the bench, including starters who are resting for the current game. However, if you choose to enter one or more players in these lists, DMB chooses only from among these players when a pinch hitter is called for. If none of these players is available, the computer manager then looks to the full bench to see if another hitter could be used. The computer manager doesn't always choose the first player in the list as the first pinch hitter in the game. Sometimes it will choose to keep the top player available for a better opportunity later in the game

• The pitching chart includes your starting rotation, rules for how your starters are to be used, a list of other pitchers who may start from time to time, and the assignment of relief pitchers to various roles.
• Roles
• You can assign up to five pitchers to each of the following roles:
• Starting rotation. You identify the pitchers that make up your starting rotation and the order in which they appear. You can use a rotation with three, four or five pitchers -- just leave spots empty if you don't want to use five pitchers. You also indicate whether starting pitchers should be used in strict rotation, in rotation but with the option to jump to the #1 starter if off-days make him available, or in proportion to the number of starts made in real life.
• Spot Starters. If you want a pitcher to make occasional starts, you can designate that player as a spot starter. The list of spot starters parallels the list of pitchers in the starting rotation. If you want someone to start 20% of the time in place of the number four starter, enter this player in the fourth spot in the spot starter list, and enter 20 when you are prompted for the percentage.
• Mopup situations. You can designate up to five pitchers for the mopup role. This role is used for the weaker pitchers on the team. They will normally be used only when your team is winning or losing by a large margin and the outcome of the game isn't really in doubt, though they may appear in close games if other pitchers are not available due to injury or fatigue.
• Long Relief. You can designate pitchers for the role of long relief. Long relievers are generally used when the starting pitcher is replaced prior to the seventh inning, but will also be used in other game situations when required, particularly when a team is losing by a large margin and wants to preserve its better pitchers for future games.
• Setup Men. There are two lists of setup men, one to face left-handed batters and one to face right-handed batters. Setup men are generally used in the seventh inning or later in close games, but will also be used in other situations when required.
• Closers. There are two lists of closers, one to face left-handed batters and one to face right-handed batters. Closers are generally used in the eighth or ninth inning when the team has a lead in a close game, but will also be used in other situations when required.
• In most game situations, the computer manager uses the first available pitcher in the appropriate list whenever a reliever is called for (excluding players on the reserve roster). So it is important that you list your players in the order you wish them to be considered, with your first choice at the top of the list. However, there are other situations where another choice will be made. If the bullpen has been used heavily, the computer manager may use the most rested pitcher. If either team has a big lead, it may choose to use a less talented pitcher to make sure your top pitchers are rested for future games. If a game goes into extra innings, everyone in the bullpen is a candidate to enter the game.
• Enter a pitcher on more than one list if you want him to be considered for more than one role. For example, your top setup man may also be your number two closer. However, there is no need to fill up all of the lists, since the computer manager chooses from other lists if nobody in a particular role is available.

• There are twenty tactics for which you can influence how the computer manager makes its decisions:
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• seven govern offensive plays: bunting for a hit, sacrifice bunting, squeeze bunting, using the hit and run, stealing, baserunning, and taking pitches.
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• four influence how frequently pinch hitters will be used in various situations: for a pitcher, for a non-pitcher, for a platoon partner, and in the late innings of a blowout.
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• three affect defensive tactics: holding runners, guarding the lines, and bringing the infield in.
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• and six help determine how the pitching staff is used: pitching around hitters, intentionally walking hitters, pitching out, making pickoff throws, using relief pitchers, and using closers.
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• The values you can set for each tactic are Most Frequent, More Frequent, Neutral, Less Frequent, and Least Frequent.
• Playing the Percentages


• For each of these tactics, Diamond Mind has studied play-by-play data to analyze the frequency with which they are deployed by real-life managers. We have examined how those frequencies are affected by the inning, number of outs, the score, baserunner locations, the ability of the players involved, and other factors.
• When set to Neutral, the computer manager attempts to replicate these real life patterns by choosing, for example, to bunt with only the best bunters in the most appropriate bunting situations and when the batter wouldn't do better against this particular pitcher by swinging away. In other words, if you set everything to Neutral, the computer manager plays the percentages.
• Based on an analysis of thousands of real-life games, the computer manager knows the odds of winning a game in any situation (such as when you're the away team and down by a run in the seventh), and it knows the probability of scoring a certain number of runs in any situation. So it sometimes plays for a big inning, and sometimes it plays for one run, whichever gives it the best chance to win. And it preserves the element of surprise, so you cannot always predict what the computer manager will do in a particular situation.
• If all of your manager tendencies are set to Neutral, a team with more good base-stealers will steal more often than a team with fewer good base-stealers. A team with more good runners will take more extra bases on hits and flies than a team with fewer good runners. This is equally true of real-life rosters and draft-league rosters.
• The other settings are intended to override the computer manager's natural inclination to play the percentages. If you want your team to sacrifice bunt less often, despite having many good bunters, set your Sacrifice bunting tendency to Less Frequent or Least Frequent. If you want your team to try to pressure your opponent into making throwing errors, set your Running tendency to More Frequent or Most Frequent. But be aware that being more aggressive may mean taking more chances than the percentages would normally call for.

• What the settings mean

• Because there are too many variations in game situations and talent levels among different rosters, there are no precise answers to the question, "What will the computer manager do if I choose this setting?" However, you may want to consider the following when making your choices, then play some games using the computer manager to see how it handles your team in different situations:
• Bunting. As is the case with all tendencies, a player's bunt rating is still the most important factor in determining how often the computer manager asks a player to bunt, but you can use the three bunting tendencies to increase or decrease bunt attempts by the players on your team.
• The Squeeze Bunt tendency is used whenever there's a runner on third with less than two outs. While it is true that some real-life managers will use the sacrifice bunt with runners on first or third in order to move the runner from first to second and holding the runner at third, the DMB computer manager does not use this tactic. It prefers not to give up an out when it already has a runner in scoring position.
• The Bunt For Hit tendency is used whenever there are two out, the bases are empty, and in a couple of other situations where runners are on base but sacrificing makes little sense. For example, with a position player at the plate, real-life managers rarely call for a sacrifice with one out and a single runner on either first or second, so DMB uses the bunt for hit tendency in those situations. With nobody out, or a pitcher at the plate, it's a different story, and DMB uses the sacrifice bunt tendency in those cases.
• The Sacrifice bunt tendency is used with nobody out and a runner on first, a runner on second, or runners on both first and second. With one out, the sacrifice bunt tendency is used with a pitcher at the plate, but the bunt for hit tendency is used when a position player is batting, because real-life position players rarely sacrifice with one out. More often than not, they're bunting for a hit even with a runner on base.
• Hit And Run. When deciding whether to use the hit and run, the computer manager is looking primarily at the batter's ability to make contact (and thereby protect the runner) and the likelihood that he'll hit into a double play if he does. High strikeout rates discourage the use of the hit and run, while high rates of ground ball double plays encourage the use of this tactic. The settings for this tactic nudge the computer manager in the direction you choose by adjusting the contact-rate and GDP-rate thresholds it uses to make these decisions.
• Stealing. When set to Neutral, the computer manager is reluctant to attempt steals with runners owning low Steal ratings, since they will be thrown out too often. If you want to further restrict your steal attempts to those players with the highest steal ratings, choose Less Frequent or Least Frequent. This will not stop your best stealers from running, but will restrain other players.
• Running. This tendency governs how many chances the computer manager will take on the base paths. When the computer manager makes a running decision, it compares the chances of gaining the extra base safely to a minimum threshold based on the game situation.
• The chances of gaining the extra base are determined by the nature of the batted ball, whether the runner was going on the pitch or on contact, the running rating of the runner, and the throwing rating of the outfielder.
• The minimum threshold is based on the game situation and whether it makes more sense to play for one run (as in the late innings of a close game) or a big inning. Depending on the number of outs and where the runners are situated, the value of taking the extra base can be high or low, as can be the cost of getting thrown out. The computer manager takes these factors into consideration when deciding how high the chances of success need to be to justify taking the risk of getting thrown out.
• The Running tendency controls the minimum threshold. If you choose "less frequent" or "least frequent", the minimum threshold rises. That causes the computer manager to send the runner only when the chances of success are higher. If you choose "more frequent" or "more frequent", the minimum threshold is lowered, and the computer manager will take more chances.
• NOTE: This tendency applies to singles, doubles and fly balls. It does not affect the decision to send the runner home from third on a ground ball.
• Taking Pitches. This tendency enables you to increase or decrease the likelihood that your best hitters will have the green light to swing with three balls and no strikes. It doesn't affect any other counts. And you don't need to use this tendency to prevent your weaker hitters from swinging at 3-0 pitches because the computer manager never gives them the green light.
• Pinch Hitting. In all game situations other than blowouts, the computer manager uses a pinch hitter only if he is rated to be better than the scheduled hitter against the current pitcher. This assessment takes into account the handedness and the left/right splits of both the batter and the pitcher.
• A "least frequent" setting tells the computer manager to pinch hit less often; that is, only when the pinch hitter is much better than the scheduled hitter. A "most frequent" setting tells the computer manager to pinch hit more aggressively; that is, even when the pinch hitter is only a little better than the scheduled hitter.
• Pinch hitting in Blowouts is a different matter altogether. In these situations, the goal is not to gain an advantage, it's to replace the team's better players to reduce their risk of injury. In blowouts, the computer manager generally replaces a better player with a weaker one, so the relative strength of the players is not a concern. Instead, the Blowout Pinch Hitting tendency influences the computer manager decisions about:
  • (a) how big a lead is needed for the game to be treated as a blowout
  • (b) how early in the game it will begin to remove players.
  In blowout situations, the "In Blowouts" tendency takes precedence over the other pinch hitting tendencies.
• b>Holding Runners. When set to Neutral, all runners but the worst are held. Choosing Most Frequent causes all runners to be held. Choosing Least Frequent causes the first basemen to play behind runners with low Jump and Steal ratings.
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• Guard The Lines. This setting controls the inning in which the computer manager begins to think about guarding the lines:

Tendency	Inning
Most frequent, more frequent	7th
Neutral	8th
Less frequent	9th
Least frequent	never

Infield in. This setting controls the inning in which the computer manager begins looking for opportunities to bring the infield in:

Tendency	Inning
Most frequent	1st
More frequent	4th
Neutral	6th
Less frequent	7th
Least frequent	8th

• This tendency does not affect the decision to bring the infield in at the corners, which can occur anytime during a game to discourage a batter from bunting.
• Pitching Around and Intentional walk. The computer manager issues Intentional Walks with first base open and a dangerous hitter at the plate if the on-deck hitter is much less of a threat. If the Intentional Walk tendency is set to Most Frequent, the computer manager will issue a walk with a smaller difference in hitting ability between the next two hitters. If it is set to Least Frequent, the computer manager will issue the walk only if the current hitter is even more dangerous relative to the on-deck hitter.
• If the next hitter is more dangerous than the on-deck hitter, but not to a large enough degree to convince the computer manager to issue an intentional walk, the computer manager might instruct the pitcher to pitch around the next hitter. The pitching around tendency is very similar to the intentional walk tendency in that it determines how large the gap in hitting ability must be to justify the decision to pitch around a hitter.
• Pickoff Throws and Pitchouts. Both of these tactics are used to slow down opposing base stealers. You may find that the "most frequent" and "more frequent" tendencies are helpful, especially if your pitcher and catcher are not especially good at shutting down the running game without a little extra help. Keep in mind, however, that pitchouts can give the hitter an advantage in the ball-strike count and too many pickoff throws can lead to errors and/or wear and tear on the pitcher's arm.
• Using Relievers, using closers. The decision to use a reliever is very complex. Each decision involves so many factors -- including the inning, score, location of baserunners, quality of the current pitcher, quality of the potential reliever, left/right matchups, fatigue, the makeup of the pitching portion of the manager profile, fatigue, and more -- that it's not possible to lay out simple rules that tell you exactly how these tendencies will affect the computer manager's decisions. The basic idea, however, is that they influence how quickly the computer manager will make the move to bring in a reliever (in non-save situations) or the closer (in save situations) when the current pitcher begins to get into trouble.

Ballpark Usage

• . . . ballparks play a large role in DMB. When players are created, their raw statistics are adjusted for the statistical impact of their home park. This (along with the era-based adjustments) helps us create park-neutral ratings for all players. And when you play a DMB game, the nature of the home park plays a significant role in the outcomes of games played there.
• These park adjustments add realism to your DMB games. If you use the real-life rosters and the real-life schedule, the park effects that are removed during player creation are cancelled out by those that are added during game play, so the players will produce statistics in DMB that are very consistent with their real-life stats. If, on the other hand, you draft new rosters, many of your players will be playing their DMB games in different parks than in real life, and the change in parks will have an impact on their DMB statistics.
• This is the way it should be. In real-life, when a hitter is traded to a hitter-friendly park, you expect their statistics to rise even if their talent level doesn't change, and you discount their real-life stats for the effects of their new home park. The same is true in DMB. If you move a player to a new park that is quite different from his real-life park, you can expect to see his statistics be affected by this move.

• If you choose to create or modify parks, keep in mind that the statistical park factors are the most important of these groups of ballpark ratings. If you move a fence back by 20 feet, it won't decrease the number of homeruns hit in that park unless you also adjust the homerun factor. If you change the surface from grass to artificial turf, it won't increase the number of extra-base hits unless you also increase the doubles and triples factors.
• Why not? Because we haven't yet figured out how to isolate all of the things that affects the statistics produced in a ballpark. How much will the rates of doubles, triples and homers be affected by a 20-foot change in wall distance? By raising the fence by 10 feet? By putting in a new type of artificial turf? Adding a new tier of seats that changes the wind patterns? Or blocking off the center field seats so hitters can see the pitched ball better? We don't know for sure.
• But we can measure the overall impact of each park through careful study of home and road statistics, and we can capture that overall impact through the statistical park factors. If a park consistently increases doubles by 30%, we can give the park a rating that will produce a 30% increase in your DMB games. To that extent, we don't need to know precisely how much each of the factors is contributing to this 30% figure.