Statistical Analysis FAQ


How can we use statistics to analyze players?


If youíll give me a moment to speak, Iíll be glad to tell you. Though the truths that follow apply at all levels, keep in mind that the emphasis here is to use statistics to arrive at an educated guess of whether or not a minor leaguer will go on to have a productive Major League career.


What can statistics tell us?


Statistics can lead us to make a lot of assumptions about a player without ever having seen him. We can assume whether a player is fast or slow based on his stolen base numbers. We can assume the quality of his bat based on his batting average. We will generally assume a pitcher is bad if he has a high ERA. Sometimes these assumptions are dead-on. Sometimes they are greatly misleading. Statistics provide significant material to infer the qualities of a player, or lack thereof, because of his numbers. Taking a step past the quick and easy inferences and heading toward interpretation is what Baseball Examiner is all about. How do we properly interpret statistics without inferring an inaccurate assumption?


Hey! I thought I was the one asking the questions here!




So, how do we properly interpret statistics without inferring an inaccurate assumption?


Good question! There are several factors to include in the proper interpretation of statistics. Weíll address those factors one by one.


When analyzing players, do statistics tell us everything we need to know?


No! There is plenty of helpful information in statistics, but there is plenty it does not tell us. It does not tell us the strength of a playerís arm, the softness of his hands, or the mindset of his approach at the plate or on the mound. The scouts will give us more information regarding a playerís tools than we can ever infer or interpret, but statistics are a form of litmus test to see whether a player is fulfilling or exceeding his potential.


So, which stats lead us to a more proper interpretation of a playerís skills?


Letís start by discussing which stats are often misleading. When analyzing pitchers, perhaps the most misleading stat is record. A pitcherís record does not tell us how well or poorly he has performed. It is a team stat. Teams win and lose, not individuals. Sure, the better a pitcher does the more likely heíll win. But so many other factors are to be considered in the outcome of a game. Does the team have a powerful lineup? Or is it sickly? Pitchers can also get no decisions due to a late-inning comeback after theyíve left the game for outings which they deserved either a win or loss. Record is a team stat.


The better the pitcher is, the better heíll give his team a chance to win. But he can only do so much. Ben Sheetsí 2004 earned-run average is nearly two full runs less than Mark Mulderís (2.70 to 4.43). But Mulder was 17-8 and Ben Sheets was 12-14. Pitchers win or lose with their team.


Well, if record is a misleading stat, then surely ERA will tell us whether he is any good.


Thatís not a question, but Iíll respond anyway. ERA is indeed a better indicator than is pitching record, but it is still not sufficient. ERA is more effective on a quick glance basis because it is a generalization. ERAs under 3.00 are more impressive than ERAs under 4.00 which are more impressive than ERAs under 5.00. But Baseball Examiner is not in the business of quick glance generalizations. We want to get more into the nitty gritty than that.


The problem with ERA is that there are other weighing factors outside of what the pitcher can control. Is the pitcher helped by a good defense thus making him look better than he ought? Or is his ERA tainted by a bad defense? Sure, a bad defense will allow unearned runs that donít count toward the pitcherís ERA, but a bad defense will also allow base hits to sneak through and baserunners to advance on plays where no error is ruled. A pitcher may have to get 4 or 5 outs to escape an inning without a single error being officially committed. And itís all earned!


A starting pitcherís bullpen will also affect his ERA. Example: two pitchers throw identical games, the same pitch sequences, the same ball and strike counts, etc. Pitcher A goes 6 1/3  innings, allowing 2 earned runs on 7 hits and 3 walks with 6 strikeouts. Pitcher B goes 6 1/3 innings, allowing 2 earned runs on 7 hits and 3 walks with 6 strikeouts. Who was more impressive? Neither. With identitical performances, they both have an ERA of 2.84 for this outing. However, they both exit the game one out into the 7th inning with the bases loaded. Pitcher A has a bullpen that comes in and slams the door. His 2.84 ERA remains intact. Pitcher B has a bullpen that throws gasoline on the fire and all 3 inherited runners score bringing his earned run total to 5 and his ERA for the outing to 7.11. Now who appears to have had a more impressive outing? 2.84 or 7.11? Donít fall for it! They were identical performances!


Itís possible that over the course of a long season, a bad defense and bad bullpen can make a better pitcherís ERA higher than an inferior pitcherís ERA that has been aided with a good defense and good bullpen. And we havenít even discussed ballpark effects!


If ERA can even be misleading, then what stats do matter?


Well, weíve already stated that a bad defense can give up additional base hits. But hits per inning is still getting us in the right direction. More effective than ERA is looking at how many baserunners a pitcher allows. The less frequently that opposing batters reach base, the less likely they are to score runs. The two main ways batters reach base are via hit or walk. So, what helps a pitcher be successful? Limit the hits and walks allowed.


If there are factors outside of what a pitcher can control to affect his statistics, then what can he control?


If a pitcher doesnít want to take the chance that the defense will blow a play, the best thing to do is get an out without making the defense have to do a thing. That is what we call a strikeout.


On the flip side, giving up a homerun allows baserunners (and of course runs) that the defense never even had a chance to make a play on. Itís better to allow the defense an opportunity to make (or break) a play than give up runs with no play at all.

The pitcher who, relative to innings pitched, keeps his hits, walks and homerun totals low while striking out a bunch is a guy weíre going to focus in on.


So, if thatís how we interpret a pitcherís stats, what about hitters?


Studying a hitterís stats is not too disimilar, only reversed. If a pitcher wants to keep batters off base, in the yard, and turning back to the dugout without putting the ball in play, then a hitter wants to get on base, knock the ball out of the yard, and put the ball in play before turning back to the dugout. Translated: On-base Percentage, Slugging percentage, fewer strikeouts per at-bat.


What about batting average?


Batting average is a good thing. Itís just that it doesnít tell you enough. It tells you the number of hits per AB, but it doesnít tell you what kind of hits. Are they all singles? Or are several extra-base hits included? Is Ichiro Suzukiís .372 batting average (with all but 14% of his hits singles) more valuable than Barry Bondsí .362 (55% extra-base hits including 45 homeruns)? Would you rather have Albert Pujols batting .330 (with 99 extra-base hits) or Juan Pierre batting the same (with only 37 extra-base hits in 86 more at-bats)? Slugging percentage tells you more about each hit than batting average does.


As we discussed with pitchers, what is the other common way to reach base other than hit? Draw walks. On-base percentage is useful because the opposite of OBP is virtually out percentage. Being out only 65% of the time (.350 OBP) is better than being out 70% (.300 OBP).


Are you saying batting average is meaningless?


No way! I just want to know more about each plate appearance than a hit ratio. What kind of hits are they? How often does he make an out? In fact, batting average is still utilized because it is already incorporated into both OBP and SLG.

A .280 batting average contributes 80% of a .350 OBP. With a .500 SLG, a .300 batting average makes up 60% of the SLG, representing all the singles the hitter gets. The other .200 of the SLG is a result of his extra-base hits. Therefore, in the increasingly popular on-base+slug statistic (OPS), batting average is counted twice! So, looking at OBP and SLG are not eliminating batting average. Itís already included! But OBP and SLG tell us more.


Is there anything else about a hitterís stats we should know?


Iím glad you asked. Weíve already discussed both walks and strikeouts. But we discussed them separately. Now letís put them together.


Are you saying strikeout-to-walk ratio is important?


Well, itís not the ratio that is as important as it is each of them in relation to at-bats. Example: players A and B each have 500 AB. Player A has 100 strikeouts and 100 walks; a 1.0-to-1.0 ratio. Player B has 35 strikeouts and 35 walks; a 1.0-to-1.0 ratio. They have the same strikeout-to-walk ratio, but those numbers tell us the two players have a drastically different approach to hitting. Player A is patient at the plate yet takes big cuts. Think Jim Thome or Lance Berkman. Player B is less likely to have the same kind of power stroke and may be more unpatient at the plate so he doesnít go deep into counts. Think Orlando Cabrera or Endy Chavez. No one had better confuse Jim Thome for Endy Chavez simply because they may have similar strikeout-to-walk ratios!


Then how do I best analyze strikeouts and walks?


Weíve already started doing that with the Thome and Chavez example. We can interpret from those numbers a hitterís approach at the plate. Letís start with walks.


A hitterís walk total tells us about his plate awareness. A good eye with a patient approach will always draw the occasional base on balls. One walk per 10 at-bats seems to be an adequate ratio. Anything less than that is cause for concern. The more a hitter draws base on balls the more he shows that he not only has a good eye at the plate but the patience to keep from swinging at balls out of the strike zone.


A player, then, who lacks the discipline to avoid swinging at bad pitches will, of course, swing at bad pitches. His strikeout total will rise. If the strikeout-to-walk ratio is more than 2.0- or 2.5-to-1.0, we have another cause for concern. Put our two causes for concern together (less than 1 bb per 10 ab and a strikeout-to-walk ratio worse than about 2.5-to-1.0) and weíre throwing up a red flag as an alarm to stay away!


An example of a red flag candidate is 30 walks and 110 strikeouts in 500 at-bats. Translation: he whiffs a lot with little patience or discipline at the plate. Sure, he might hit some homers. But he had better! If heís not hitting homers heís not doing much to help offensively.


Guys can be productive at the Major League level with 30 walks and 110 strikeouts in 500 at-bats! What gives?


Remember that our emphasis is to judge whether a minor league player will go on to have a productive Major League career. A player with strikeout and walk totals like that in the minor leagues will get torn up, eaten apart and spat back out in the bigs. Heck, even players who have solid strikeout and walk totals in the minors will come to the big leagues and struggle to duplicate the same ratios.


For examples, see Reggie Sanders (118 strikeouts and 33 walks in 446 at-bats) and Jason LaRue (108-26 in 390). Sanders does provide offensive contributions with homers and stolen bases despite his strikeout-to-walk ratio. LaRue doesnít do as much as Sanders offensively but plays a more premium position defensively. In the minors, LaRue had a strikeout-to-walk ration of nearly 2-to-1 and Sandersí ratio was 1.74-to-1. Against major league pitchers in 2004, they combined for close to four strikeouts per base on balls. The Majors is a whole different game and if a player doesnít have a good approach against several pitchers who will never see the big leagues, heíll likely struggle against those who are already there.


But there are also exceptions when a player with a horrid strikeout-to-walk ratio still develops into a terrific hitter. See Alfonso Soriano. He provides MVP-type numbers with a horrible strikeout-to-walk ratio. But let me add this point: in the 2003 World Series, Soriano was exposed for being the free-swinger that he is and he had such a miserable series that he was eventually benched and subsequently traded. Even his huge numbers could not hide his lack of discipline at the plate. A disciplined approach at the plate is essential for a minor leaguer to expect success in the Majors. If his approach is poor, he will be exposed and the results are often poor.


What about power? How can we tell if a minor leaguer will hit homeruns in the Majors?


Donít necessarily trust minor league homerun totals to predict power potential. Oddly enough, guys with low homerun totals in the minor leagues can end up being powerful Big League bashers. Power is typically the last tool to develop. And most minor league bodies havenít completely filled out yet. Even among those with great power potential, minor league homerun totals may be quite modest. Therefore, there must be an alternative to homeruns for predicting future power. There is.


What would a hitter need in order to realize homerun power when his body has filled out and heís experienced enough with the bat to incorporate a loft into his swing? Answer: a good approach at the plate and a producer of hard line drives that go for extra bases.


The best indicators of potential future power are strikeout-to-walk ratio and extra-base hits. Guys that put up large double totals are candidates for future homerun potential once he learns how to turn his gap power into over-the-fence power. Couple that with a disciplined eye at the plate, and youíve got a guy that is willing to wait for his pitch and drill it.


Of course, a lot has to do with his age. This is mostly true for younger players. The older he becomes, the more he realizes his actual ability and there is less wondering about his potential.


What does age have anything to do with a minor leaguerís prospect status? If heís putting up good numbers, heís going to be a good player, right?


Age plays a tremendous role in determining a playerís status as a prospect. Imagine the following scenario involving three high school players who post identical numbers: Player X is a senior playing for the varsity team and he is considered a quality player. Player Y is a freshman also playing for the varsity team and produces the same statistics. Player Z is a senior with identical performance but he is playing for the junior varsity team. Who is the best player?


Player Y would be considered the best of the three because he is producing at a quality level exclusively against kids older than he is. If heís already good against juniors and seniors when heís still just a freshman and itís not expected of him, how much better will he be by the time he is a senior? Player X is producing at a quality level against those of his same age and level of experience. Good for him! Player Z puts up the same numbers as the other two, but heís a senior doing it against sophomores and freshmen. Heís just a big bully feasting on less developed players. Itís expected that he would produce. Shame on him if he didnít.


The same is true in the minor leagues. Donít be starstruck just because a minor leaguer put up gaudy numbers. He could be a big bully playing against younger competition.


So how can I know if a minor leaguer is considered young or old for his level of competition?


Each minor league level has its typical range of age. There is Triple-A, Double-A, two divisions of Class A (high and low), and several short-season leagues. Since Triple-A is filled with so many veterans, the age range is extremely diverse. So letís start at the bottom and work our way up.


There are three divisions of short-season ball: Rookie leagues, Advanced Rookie leagues, and short-season Class A leagues (They are termed short-season because the leagues play only two months Ė July and August). Rookie leagues are typically filled with former high schoolers who have recently signed since being drafted; either just weeks before in June, or the year before. Therefore, most of the players will be 18 or 19 years old. Also in the Rookie leagues are young foreign-signed players like those from the Dominican Republic. Foreign born players can sign a professional contract as young as age 16. A 17-year old having success in Rookie ball is promising. A 20-year old is expected to do well against teenagers.


Advanced Rookie ball may also see several recent high school draftees, age 18 or 19, but also should face some recent college draftees. Most of the collegians will be 21 or 22 years old.


Short-season A ball should exhibit several recent college draftees or players signed out of high school who have one or two years of Rookie ball experience.  Therefore, the typical age range in short-season A ball is 20-22.


The lowest level among full-season leagues is low Class A featuring several players between ages 21 and 23. A decent prospect should not be older than 22 if he is still in low Class A ball. If a teenager puts up good numbers at this level, look out! He could be dynamite.


A year later, most of those players will be in high Class A ball. And of course theyíll be a year older, typically ages 22 to 24. The 24-year old still in A-ball is not likely to be making much noise as a prospect. Many of baseballís better prospects are already in the Major Leagues by age 24.


A player who is in low-A at age 21 and is moving a level a year will reach Double-A at age 23. These days, Double-A can sometimes be a stepping stone straight to the Majors, even jumping Triple-A. A 23-year old producing in Double-A still shows good promise. A 21-year old producing well in Double-A should be a knockout! Just ask the Marlins. Entering the 2003 season, Dontrelle Willis and Miguel Cabrera started in Double-A at ages 21 and 20, respectively. Before their season ended they had helped lead their Parent club to a World Series title.


Using another example while sticking with the Marlins theme, World Series MVP Josh Beckett was promoted to Double-A just a month after his 21st birthday in the 2001 season. Just three examples of what kind of core individuals it takes to win a World Championship. All three were 21 or younger by the time they reached Double-A.


To restate, the age range in Triple-A is so broad itís difficult to narrow down. But letís look at a typical path to reach the Majors for a mid-level prospect who was drafted out of college. Selected in the June Draft as a junior and subsequently signed, he could get immediate experience in a short-season league at age 21. In his first full professional season he will start in low-A ball at age 22. The expectation for minor leaguers is to advance a level with each season. Following that path, heíll be 23 in high-A ball, age 24 in Double-A, 25 in Triple-A and potentially get an opportunity to succeed in the Majors at age 26. Anything older than that path should be considered below the bell curve and less likely to be considered prospects at all. The more special a player is, the younger he will be at each of those levels as he likely makes a rapid ascent to the Major Leagues.


Therefore, age plays a significant role in the prospect status of a minor leaguer.


Now do I have everything I need to know in order to recognize a good minor league prospect?


If we knew everything there was to know in order to distinguish those with the greatest promise from those of ordinary skill, weíd be working in Major League front offices. But then again, they canít even seem to figure it out all the time. None of us really, truly ever know for sure. And thatís what makes it so much fun.