The Other Side of Things

If you’re ever having trouble understanding a particular stat, try to go to this page first.  If you still can’t understand it, let me know.  If there are stats I haven’t added in here, please tell me and I’ll add them.  Thanks to Baseball Almanac for the stats.

Offensive Stats

RBI – The most useless statistic in baseball when evaluating individual performance.

PA – “Plate Apperances” -At-Bats + Bases on Balls + Hit By Pitcher + Sacrifice Hits + Sacrifice Flies + Times Reached on Defensive Interference

OBP – “On-Base Percentage” – (Hits + Walks + Hit-By-Pitch) divided by (At Bats + Walks+ Hit-By-Pitch + Sac Flys)

SLG – “Slugging Percentage” – Number of (Singles + [2 x Doubles] +[ 3 x Triples] + [4 x Home Runs]) divided by At Bats

OPS – “On-Base plus Slugging” – Your OBP plus SLG.  It is often used as an index for rating an overall player’s performance and production versus his fellow players.

RC – “Runs Created” – On Base Percentage x Total Bases.  This was created by Bill James as a measure of total offensive production.

wOBA – http://www.insidethebook.com/woba.shtml

APRO (PRO) – “Adjusted Production” – (On Base Percentage divided by League OBP) + (Slugging Average divided by League SA) -1.

Have you ever thought to yourself that some players are really helped by the park that they play in?  This is a tool to show you how productive they are by using on base percentage and slugging percentage – but also factoring the average of each player.

The adjusted production statistic is a park and league adjusted version of on base plus slugging percentage. It is specifically used and created by Total Baseball for comparison of players from different eras in different parks. This is an advanced statistic which requires the complete understanding of on base percentage, slugging average and a park adjustment factor. Total Baseball has adjusted OBP and SA for the player’s home park and League OBP and League SA are the league average for each statistic respectively. As in OPS, the decimal point is dropped when APRO in seen or used.

Pitching Stats

ERA – “Earned Run Average” – (Number of Earned Runs x 9) divided by (Number of Innings Pitched).  ERA is one of the most understood stats in baseball – but here’s the thing I don’t like – it’s not a useful tool to measure relievers value.  Think about it, if a pitcher throws eight scoreless innings in relief, he’s done a really good job.  If his 9th inning he just doesn’t have it, and gives up three runs – his ERA is 3.00 – a little above average.  Also, if a reliever enters the game, with the bases loaded and 2 outs, and proceeds to walk the next three batters, but get the third out right after that, his ERA for the day is 0.00 – but he didn’t necessarily pitch good.

W – “Wins” – One of the most useless stats in baseball.  Much like RBI, it is a team statistic.  You can give up 11 runs in 5 innings, but if your team scores 12, you’re in line for the victory.  Conversely, you can pitch 8 innings and gave up one UNearned run and lose the game if your team never scores.  Poor stat to predict the future of a pitcher or how well he has been performing.

ERA+ – “Earned Run Average Plus” -  League ERA (divided by) ERA.  This statistic uses a league normalized earned run average in the calculation and is meant to measure how well the pitcher prevented runs from scoring relative to the rest of the league. It is a similar to the hitter’s PRO statistic and when calculated the decimal is also dropped here.

WHIP – “Walks plus hits over innings pitched” – (Hits + Walks) divided by Innings Pitched.  An extremely popular statistic that is primarily used and discussed with the Fantasy Leagues and Rotisserie Leagues. Developed to measure the approximate numbers of walks and hits a pitcher allows in each inning he pitches then compares the value received to other pitchers to formulate a pitcher’s index.

SV – “Saves” – A pitcher can earn a save by completing ALL three of the following items:

1. Finishes the game won by his team.
2. Does not receive the win.
3. Meets one of the following three items:
   1. Enters the game with a lead of no more than three runs and pitches at least one inning.
   2. Enters the game with the tying run either on base, at bat, or on deck.
   3. Pitches effectively for at least three innings.

FIP – or Fielding Independent Pitching, which calculates a pitcher’s responsibility for the runs he allows based on his walks, strikeouts, and home runs allowed. The FIP formula is (HR*13+(BB+HBP-IBB)*3-K*2)/IP, plus a league-specific factor that scales FIP to match league average ERA for a given season and league. For the win value purposes, we modified the league specific factor to scale FIP to RA instead of ERA.  Why?  There are so many extra variables that go into a pitcher’s ERA that the pitcher himself simply doesn’t have control over. We have to try to extract the pitcher’s responsibility from his team’s run prevention while he’s on the mound.

Defensive Stats

Fielding Percentage – (Putouts + Assists) divided by (Putouts + Assists + Errors).  The fielding average, or fielding percentage, defensive statistic is the most common rating system being used in baseball today. It is meant to measure the success rate of fielding opportunities by each player. The official scorer for each game plays a role in this statistic by determining if the hit ball would have required an ordinary amount of effort to turn the play (thereby charging an error to the fielder if they did not turn the play) or an extraordinary amount of effort to turn the play (which does not result in an error charged to the fielder). The downfall to this statistic is that it almost rewards fielders who choose not to attempt a difficult play, thereby avoiding the error, to those that try to turn every hit ball into a possible out.

Zone Rating – STATS, Inc. developed their own defensive rating system to also track locations of EVERY hit ball for EVERY game played – similar to the above Defensive Average statistic. The Zone Rating system is different because the area of responsibility, or zone, for each fielder is considered a “playable” area and does not account for balls hit into “Bermuda Triangles”, “No Mans Land” or other impossible to field balls. A fielder that turns a double play is credited with 2 outs in the ZR system as their play on the ball actually resulted in both outs versus Defensive Average which only credits the 1 out. STATS, Inc. books area available at every bookstore and their work is updated on a yearly basis for player comparisons.