Earlier posts about this topic:
Team Defense in Football and Baseball Betting #1
Role of Team Defense in Baseball and Football Betting #2
Baseball and Football Betting: Team Defense #3
Defense in Football & Baseball Betting #4

How Important DER in Sports Betting

Defensive Efficiency Rating is a simple measuring system. It is based on the number of the stricken balls (except home rounds), which then are turned into outs. The main prerequisite for DER is that the defenders of the team have to catch every ball, which was batted on the field, except home rounds. The average DER for all the teams constitutes about 70%. In other words, 7 of 10 batted balls (except homers) will be turned into outs.

DER may look like quite a rough evaluation of the defensive ability, as the defense depends on the pitchers very much. A good pitcher, of course, can improve the defensive rating, and at the same time a bad pitcher can reduce it. And DER does not take into account the influence of the game park. Some parks are better for the defense than others.

In spite of its imperfection, DER refreshes, because (like ZR) it allow us to avoid the subjective nature of fielding percentage. And finally, counting the fielders’ responsibility for the balls, which were batted in their zones, it doesn’t seem very severe, because this is the reality of the game.

Summing up the discussed information, I would like to notice that the betting statisticians are used paying attention to the defense less than pitchers and batters. The good news: statistical minds and other gurus have recognized the problem and work on the improving of characteristics, which allow to evaluate the quality of playing on a field.

From the position of betting, we can’t say how important the evaluation of defense is, when you forecast the final result of a competition.

It might be less important than hitting and pitching, but you can’t fully ignore the defense during the baseball handicapping. Though Zone Rating and Defensive Efficiency Rating are not perfect, but they are very reliable. At least they are much better than just fully ignoring of defense or using the useless indices like “Fielding percentage”.

What is Zone Rating in Sport Betting?

The main sport channels, ESPN, shows the Zone Rating as percentage, which was evaluated by STATS Inc., of balls on the player’s field in his typical defensive zone. STATS Inc. is one of the leading providers of the statistical information in the spheres of professional sport and sport competitions, which has been tracing the position of every particular ball in every game since 1990.

To define the ZR, the field is mentally decided into 20 different zones. Every player in turn is responsible for every ball in his zone. And he doesn’t responsible for any balls outside his zone. In fact, it is the definition for ZR as a parameter. To concrete, it is a field, which has the shape of a heart (as the hearts in a deck of cards) and is cut into many thin pieces. The bottom of the heart is home plate. And every player on the field is responsible for all the fitlding balls, which were thrown in his zone.

The main prerequisite of a zone is that a fielder is considered to be responsible only for the moment, in which he really can struggle (i.e. write “out” into his account). ZR just counts the total number of the outs, which were registered by a fielder and the total number of possibilities (hits) in his zone. Just in case if you want to know the average ZR for all the teams it’s about 85 percent. At the average the MLB players will make outs in 85% of 100 hits in their “zone”.

Zone Rating Can Be Very Useful When Bet on Football or Baseball

You should know some things about ZR. At the beginning of a game not all the balls are counted. The balls that were thrown lower than the line, higher than the middle or in nobody’s (i.e. not assigned) zone, for example, are ignored. If ZR has a problem, it is only that the zones are very thin and the players with “good hands” receive an advantage over the players with “good radius of action”. But STATS obviously made the smaller zones purposefully in order to reduce the possibility of the players, so they can’t “encroach” into the zone of their neighbours.

Even in this case, ZR gives a head start to fielding percentage in amount of 100 points, as a criterion for evaluating the defensive ability. Unlike fielding percentage, there are no subjective elements in ZR, as ZR clearly defines the obligations (of zone), every fielder of which is supposed to be responsible. When we choose fielding percentage, we allow the referees to be responsible for the mistakes, as their opinions may be different from each other (that is why at least one of them will be mistaken) when they interpret the same game situation.

I also critically consider the individual components of the “Fielding percentage” formula. Such indices as Assists and Putouts of “Fielding percentage” are affected by so many other factors that the “pure” consideration of them may mislead. Let’s exam, for instance, Assist. Now, for example, Miguel Tejada, who plays in Orioles, is the leader of short-stop MLB among Assists.

Does it mean that Tajada is the best short-stop in baseball?

Or does he appear to be the leader of shot-stop MLB because of other reasons, may be: he plays more innings than his mates shot-stops, he plays behind the pitchers, who throw more ground balls than others; he just has more possibilities because of his position when he play? We just superficially considered here this problem, also there are many other hypothetical examples. And Putouts include the same defects.

Of course when we only complain about this problem and do not offer any decisions, then such an approach only makes us similar to the people, who grumble and worry too much about their problems. While we can’t offer a great panacea to evaluate the defense, at least we can offer some less known indices that, in my opinion, are more useful. These two indices, which we are going to consider, are Zone Rating (ZR), and Defense Efficiency Record (DER).

Don’t be annoyed if you suppose these betting statistical data to be a gibberish.

These are the efficient data, which you can find on the main sport websites. There are other kinds of the team defense, which can be understood only by experts, for example, Win Shares that was developed by Bill Jameson, the baseball historian. But while this system is adapted by the people, it is not very useful for handicappers, as they can’t find its daily information before the games.

On the other hand, usually the most common used method of defense evaluating is a notion, which is very close to the idea of “Fielding Percentage” and its individual components, but they, unfortunately, are not adequate at all. “Fielding Percentage” is the total number of Assists (A) and Putouts (PO) of a player (team) divided into Assists (A), Putouts (PO) and Errors (Е), made by the same player (team).

For instance:

If Miguel Tejada has 256 putouts, 473 assists and 20 errors, his “Fielding percentage” is equal to:
.973 ((256+473)/(256+473+20))

This kind of evaluation is so imperfect that you can write a multivolume treatise about its restrictions. To save your time, let’s describe only some main items.

Our first problem concerning “Fielding percentage” is that this index by its nature is subjective. It means that only one official referee can define whether the players should be blamed for an unsuccessful attack. Two different referees would be able to give two different inferences about the same game situation, only because of their subjective interpretations. Very often “Fielding percentage” imposes a penalty on the players, which have more wide playing range.

Let’s concretize the last thought. Imagine for a moment that a hitball is between short-stop (SS) and the second base (2B). In perspective, not to spoil the statistics of “Fielding percentage”, the short-stop would theoretically allow the ball to play easily, instead of to make an attempt “to dive” for it and then to make a bad throw. In the game it is obviously that the bigger sector is “protected” by a player, the better player is.

But in fact «Fielding percentage» can indicate the player who has a worse playing range, but the better position in the stats list. I call it a fruitless effort.

Forecast Result in Baseball and Football Betting: Defense

But when the same handicappers were asked, “Is it truth that the defense of a team is very important when you forecast baseball results?” The most beginners said, “No”; and at the same time about a half of the professionals answered, “Yes.”
This survey, admittedly, was elementary, but it was made to confirm a problem, the existence of which has been suspected for many years.

The essence of this issue is that the most baseball handicappers pay their attention on the pitchers and batters, and almost ignore the defensive ability of a team. It may sound ironically, but the most handicappers agreed that the defense of a team influences on the match result, and besides this fact they still exclude the defense when they forecast the results of baseball matches.

We consider such a strange, dynamic ignoring of this aspect to be the result of the restricted estimation procedure. It means that it is more difficult to estimate the defense of a baseball team, than other main sport competitions (NBA and NFL).

Particularly, the amount of components in the baseball defense complicates this estimation.
The great number of factors includes: different field width of different stadium, different surface of the fields, understanding of the game situation, position, decision making and many other things.

But how does a handicapper evaluate the subtle factors such as: decision making and understanding? It is supposed not so easy to be done. This fact explains why the most handicappers generally ignore the defense.

Betting Factors That Help To Win

There are no problems with hitting and pitching when you evaluate both players and teams in whole. There are some factors, which allow to evaluate pitchers quite correctly: ERA, WHIP, Strikeouts SO, Bases on Balls /Walks/ – BB, Home Runs HR, etc. Such phenomena as: On-Base Percentage (OBP), Slugging Percentage (SLG), OPS (On-Base + Slugging), batting average (ВА или AVG), runs batted in (RBI) and others are very convenient for batters’ evaluating.

Though none of them is perfect, just some of the methods are better than others. But generally speaking all these statistical indices are more than just adequate comparison and opposition of the pitchers and the batters. And at last it is the very thing, which we as handicappers are looking for.