Suppose you are now comfortable in the sports book and familiar with how propositions work. You know how to read the prop sheets and the board and how to calculate the probabilities implicit in the terms offered by the book. What next?

To know whether a bet is worth making or taking, you have to know what the real probabilities are out there in the real world. That is where handicapping comes in.

To use a concrete example, suppose the book has a line on the Steelers over the Chargers at -10'. (Remember, the hook means a half point, so a bet on the Chargers will win if they lose by 10 points or less.) At the (implicit) -110 terms, the book is predicting that there is a 52.4% likelihood that the Steelers will be the Chargers in San Diego by 11 or more points. ($110 is the cost of the bet and $210 is the payoff, yielding an "expectation" of 54.38%). So far, so good.

If the real chances - the "true odds"- are greater than 52.4%, this is a good proposition. If the "true odds" of the contrary outcome are palpably less than 50%, then it might make sense to take the other side. The example chose the Chargers because San Diego is a local team to Las Vegas. Perhaps, if a lot of "fan money" has been wagered, the book may have set the spread to be unfavorable to the fans, implicitly favoring a bet on their opponents. But suppose it is hard to say whether this 52.4% figure at 11 points is realistic. Maybe the totals bet is easier to judge.

That is where competent handicapping comes in.

Definition: Handicapping involves identifying, quantifying and combining the factors that influence outcomes.

Objective: The purpose of handicapping is to arrive at a percentage probability that can be compared with the terms of a betting proposition.

Classical statisticians may grind their teeth at the concept, for we are attaching probabilities to unique events. We are pretending that it is possible to repeat the same event over and over again a large number of times, to estimate the expected value of the outcome. The "outcome" is, in most cases, the final score. But, of course, there are many intermediate outcomes that determine the final score. In football, for example, these might include details about the performance of the coaches, the defensive secondary, special teams, quarterback, offensive line, etc. The process of handicapping involves identifying these elements that influence the outcome and predicting their value, based mainly on prior performances and current conditions (like injuries or weather).

The relative contribution to the final outcome of each relevant factor is weighted, usually by some system of points, so that they are each given their due influence. The approach is then repeated for all competitors (two in the case of football, possibly many in the case of golf, tennis and auto racing). Sometimes a handicapper will assign relative strength ratings to each competitor as a result of this research, and then adjust the ranking according to conditioning factors like weather, importance of the game or home team advantage.

From this description, it can be readily seen that handicapping sports often entails more art than science. Each sports handicapper develops his or her own techniques. Sometimes these different approaches will be called a "system." Sadly, the definitive "system" for handicapping sports has not been found, nor will it be found. The real world is just too complex for a "system" that will automatically crank out foolproof predictions of the future. The most that can be aspired to is an approach to precision handicapping, to reduce, to the degree possible, any mistakes in comparing the relative strengths of competitors. Some principles apply to how one gets started in handicapping. Though different experts have different notions, most will agree on the following:

Specialize

To understand how the process works, it is best to concentrate first on one small segment of the sports universe. As the variables in any given sport are many, starting with just one sport is a good idea. Moreover, it is best to start with some league or version of the sport that does not attract a lot of attention or action. The reason for this is that the prime leagues, like the NFL and MLB, are studied by so many people, handicapped as precisely as possible, and bet upon with such intensity, that it is sometimes hard to find a good edge. On the other hand, betting props on, say, ACC college baseball, may not be researched by the lines makers as thoroughly, and they will not attract so much action as to cause adjustments in the lines. Thus edges can more easily develop. The idea is to look for large edges, as one's confidence in the handicapping may not be as solid as it will become later. Giving as wide a margin of error as possible for the beginner is always a good idea.

Organize

Once the target sport and league have been identified, gather all the possible sources of information about the teams, their contests, their management, etc., into one place. With the computer and Internet, this is vastly easier than it once was. Newspaper articles, for example, have become much more readily available. The problem these days may be too much information - information that frequently is of a sort not totally useful for the purpose. Organize all the sources so that they are easily identified and easy to consult. This process does not end at the beginning of the project. It is on-going, as every week more data will come across the airwaves about the teams and their contests. One benefit of specializing in a relatively minor area of sports betting is that the volume of available data is fairly manageable, though potentially tricky to locate. Thus, one can hone research skills without becoming buried under a landslide of reports.

Analyze

First generation computer programmers remember that one of the clichés of systems analysis was "turn data into information." All of the organized research on earth will help little if there is no analytical framework for relating one factor to another. Most handicappers develop several spreadsheet formats for registering relevant items of information. These can be kept on a laptop and taken to the sports book. The first analytical step is just to identify, from among all the data available, which elements of information are worth capturing into the spreadsheet. For example, in baseball, surely everything about pitching and batting will be important. It will be important to devise a method to calculate a player's batting averages against certain opposing pitchers. This is always tricky, and sometimes not even possible in certain college leagues. Information on coaches, weather, place of the game, number of games played by players, overall team experience, esprit de corps, errors, etc., all are relevant. Even more importantly, personal observation of the contests will greatly improve handicapping - not only because it provides data not otherwise available, but because it helps to sort out which influences are less important, and which need to be given further weight.

One analytical issue merits specific mention. This has to do with correlations. As a matter of pure logic, two outcomes can have one (and sometimes more than one) of the following four relationships: (1) unrelated; (2) A is a cause of B; (3) B is a cause of A; or (4) A and B are products of a common cause. The first possibility says that A and B are uncorrelated. The last three possibilities result in a "correlation," something for which handicappers are constantly searching. When a relationship between two factors is found, it is important to know which of the three possible explanations is correct. If both factors are calculated into the handicapping, there is a risk that whatever this influence is on the outcome, it will be overrepresented in the results. If both factors have a common cause, then one of them may serve as a proxy for the other - a convenient situation when the data describing one factor may be easier to obtain than data on the other.

Ask the Right Questions

Clearly, handicapping can be complex and difficult. The temptation is always there just to make a stab at it. The closer your handicapping comes to guessing, the more your are like the visceral or emotional fan. At such junctures it is helpful to ask yourself, "What more could I know, that I don't know, to be able to refine the analysis?" This puts the thinking back into analytical mode. The professional will often correct the novice, who may speak of "predicting which team will win" a given game. That may be the objective of handicapping, but it is not the question handicappers ask. Rather, the question(s) will be, "What are the chances that such-and-such a team will perform better than its historical average?" Then, "How will the opposition react to that?" In short, the analytical framework is not just to identify the outcome, but rather to spot what intermediate events might or might not take place (like dropped passes in football or passed balls in baseball) to impinge on an overall view of how the game will go. Anyone who watches a game being played (without knowing the score) has a better chance of saying which team will win than a person who is not watching the game. In the same vein, the handicapper who deals with the internal details of the game will have a better chance of determining the likely outcome than someone who tries to do nothing more than guess at the final score based on the results of previous games.

Account for Motivational Issues

One reason why some fans prefer college basketball to the NBA is that they say it is more exciting. The teams are less predictable. They are more susceptible to technical mistakes and they are more influenced by emotional factors. The point is that strict handicapping will not help explain those outcomes that show a special effort by one team, or a "down" situation by another. Any approach to handicapping needs to take into account any specific motivations or de-motivations of one or the other team. This factor is most obvious when one team has a clear impulse to win (such as a "must win" situation for the playoffs or the coach's swansong game). Sometimes it is the reverse, when a team has no particular need for a victory (such as having already clinched the playoffs). The lines maker for the sports book almost certainly has taken this into account in setting the spreads or the money lines, but probably somewhat conservatively. That is to say, the extra given by the handicapper to the motivated team may not be as much as that team is capable of accomplishing under the circumstances. In college play, motivation may play an even greater role, as it affects not only desire, but also perhaps the technical competence of the play.

Evaluate and Revise

Handicapping will not improve if it is not evaluated after the event to determine how accurate it was. Many gamblers simply do not have the stomach or patience for this step, especially if the bet was not successful. Experts always advise a person to write down bets and the handicapping notes prior to making the bet. Then, after the fact, it will be possible to see if the outcome differed from the handicapping because of random variation (such is life!) or because of a mistake in the assumptions or techniques employed. A convenient way to accomplish this is to design a spreadsheet for the laptop that lists all the bets, with the "why" of the bet noted in brief and a calculation of the "true odds" and edge. Other columns would be provided for the outcome, winnings and profit. A periodic comparison of the a priori view of the contests with the a posteriori facts should cause adjustments to the handicapping approach. The comparison will also disclose any mistakes made in the betting process itself. In short, sports handicapping is a technique developed by each individual according to his or her own interests and experience. There are elements in common across different sports and for different analysts, but each person really needs to try it out. The best place to start is on the Internet, with the many resources available, both in the sport itself and among those in the gaming community who publish web sites and blogs on the subject. Sport-specific Internet forums and blogs will be particularly useful in helping to identify the essential elements of analysis.

The warning, of course, is that the rest of the gaming calculation is very precise. For example, one's edge must be large enough to overcome the house vig. None of that will matter if the handicapping is wildly inaccurate. The calculation of edge depends critically upon "accurate" handicapping. Otherwise, there is no reason to presume that the wagerer's analysis is any better than that of the casino lines maker's. Any bet becomes simply a guess in contradiction of the casino's prop, without measurable support from the intellect. Handicapping is perhaps the most important feature of sports betting; sadly, it is the one element in which a written summary can provide the least guidance.