Handicapping, in sport and games, is the practice of assigning advantage through scoring compensation or other advantage given to different contestants to equalize the chances of winning. The word also applies to the various methods by which the advantage is calculated. In principle, a more experienced player is disadvantaged in order to make it possible for a less experienced player to participate in the game or sport whilst maintaining fairness. Handicapping also refers to the various methods by which spectators can predict and quantify the results of a sporting match.
The term handicap derives from hand-in-cap, a popular 17th-century lottery game, where players placed their bets in a cap.  Handicapping is used in scoring many games and competitive sports, including Go, chess, Croquet, golf, bowling, polo, basketball, and track and field events. It also serves to foster wagering on horse racing events. Often races, contests or tournaments where this practice is competitively employed are known as Handicaps.
The term is also applied to the practice of predicting the result of a competition, such as for purposes of betting against the point spread. A favored team that wins by less than the point spread still wins the game, but bets on that team lose.
An impost is the weight that must be carried by a horse in a race. Horses carry lead weights during the course of a race as a form of handicap. Such a race is also sometimes termed a "handicap." These weights supplement a jockey's weight to give a horse his assigned impost. The jockeys use saddle pads with pockets called lead pads to hold the lead weights.
These riding weights are assigned by the Racing secretary based on factors such as performances, distance so as to equalize the chances of the competitors.
In horseracing, until 1995, for pace handicapping purposes, the time generally allotted by pace handicappers for a horse to run a length (approximately 11 feet) during the course of a race was long thought to be a fifth of a second. This long held misconception was turned on its head by the works of Gonzalo Sandoval via his research into the internal fractions of thousands of Thoroughbred horse races. The resultant formulas and algorithms are what comprise his subsequent pace handicapping work called REXPOINTE Pace Handicapping. This method of pace handicapping is used by many fans of the Sport of Kings.
Thoroughbred handicapping is the art of predicting horses who have the greatest chance of winning a race, and profiting from these predictions at the horse races. The Daily Racing Form (DRF), a newspaper-style publication, is an important tool of the handicapper or horseplayer. The DRF details statistical information about each horse entered in a race, including detailed past performance results, lifetime records, amount of money earned, odds for the particular horse in each past race, and a myriad of other information available for casual or serious study.
The handicapping process can be simple or complex but usually includes the following elements prior to the race:
1) Study of the Daily Racing Form
2) Observing the horses’ body language and behaviour in the paddock and/or post parade, in particular, its ears and tail. Ears should work together and look forward or backward. The tail should be "quiet." A swishing tail indicates something is bothering the horse.
3) Watching the tote board for the changing odds of each horse and thus for clues about how the betting public views a horse’s chances of winning the upcoming race
“Trip Handicapping” takes place during the race and involves watching the horses (usually with binoculars) and noting relevant information about how a horse runs during that race.
Handicapping theory is possibly one of the most enigmatic theories in all of sports. Horseplayers consider the following elements when handicapping a horse race:
Speed Those horses who run the fastest, win the most races. The DRF lists times at certain call points of each race, and the lengths back from the lead at each call point. Speed handicappers compare race times to help ascertain which horses will most likely win the race. The DRF now contains a numerical summation of the speed that each horse ran in every race, called a Beyer speed figure. This number is generated through a method developed by Andrew Beyer, and described in his 1975 book Picking Winners. The Beyer speed figures takes into account the individual class of a race as well as how the racetrack was playing on a particular day to create an aggregate number for each horse. The basic error behind this approach is that the sample size each day which is used to create the track variant for the speed figure is very small, and hence subject to massive errors in standard deviation. For example, there may be only one turf (grass) race on a given day, and the Beyer system has to extract a variant for that race from a sample of one.
Pace Pace is probably the single most important factor in determining the outcome of a race. Pace handicappers classify each horse’s running style (i.e. front runner, stalker, presser, closer) and then find contenders based on the predicted pace of today’s race. The difficulty is that the jockey has control over where a horse is placed in a race and how fast that race goes in the early stages. This takes the prediction of pace for a given race out of the realm of mathematics and into the realm of mere speculation.
Until the 1970's, for pace handicapping purposes, the time generally allotted by pace handicappers for a horse to run a length (approximately 11 feet) during the course of a race was long thought to be a fifth of a second. Andrew Beyer was the first to contest this in his 1975 book Picking Winners, stating that the time span of a beaten length (at the end of the race) varied by race distance, as horses would be traveling faster at the end of shorter distanced races than they would at longer ones. Others, particularly devotees of the Sartain Methodology in the 1980s, furthered this principle to include fractional (internal race) times. Today, the value of a beaten length is generally accepted to be closer to 0.16 seconds than to 0.20. The standard of one-fifth of a second is somewhat valid in Standardbred (harness) racing.
Form Those horses who looked “sharp” in their past race or past few races, win the most races. A sharp horse could have finished strongly, stayed among the leaders, finished “in the money” (1st, 2nd or 3rd) or recovered from a bad racing trip. Likewise, a horse showed dull form if it gave up, looked sluggish or chased the pack. Horses with sharp form have the lowest odds and hence return the least money per bet. Also, often horses will race off a "layoff." A layoff is a rest varying in length from usually two months to a year or more. In this case, workouts, horse appearance, and trainer patterns are the best guides to whether the horse is ready to run after a rest.
Class Horse races occur at different levels of competition. Generally, high caliber horses are entered in races with other high caliber horses and slower horses are entered in races with other slower horses. But a horse can move up or down in class, depending on where the trainer decided to enter the horse based on the results of its last race. Note that the strength of the same class of race, such as a Maiden Special Weight race, will vary greatly from track to track, as well as from race to race at the same track, making this too an inexact determinant of class.
Post Position The horse nearer the inside of a race track will have a shorter distance to run than a horse on the outside track, although it is also more vulnerable to being cut off by horses that start off faster and head to the inside rail.
Jockey Horses do not run the races by themselves. They are riden by a jockey, [male or female, (and in Quatar and UAE; by a Robot jockey)], and there are good human jockeys and bad human jockeys. All other things being equal, the better human jockey can make a difference between a winning horse and one that loses. In the case of the robot jockey; a person controls the robot by remote-control, and how well the person runs the remote control robot might be a factor as well.
Other Factors Other factors affecting the outcome of a race are track condition, weather, weight that the horses have to carry, daily bias of the racing surface, and many more factors that the handicapper cannot know.
There are other strategies that involve differences in the lines on the same event at different books. One bet is a called a "middle", which is when a player finds two books that offer different point spreads for the same event. They will bet the more favorable spread at both books, and if the final score falls between the two, the bettor will win both bets. On the other hand, if the total falls outside of the range of the "middle" the bettor only loses a small percentage of a bet (the "juice" or "vig" taken by the house).
For example, Book 1 has Team A as a 3 point favorite, and Book 2 has team B as a 3 point favorite. If a player bets Team B at Book 1, and Team A at Book 2, he will win both bets if either side wins by 2 or less points, and will win one bet and push the other (known as a "side") if either team wins by 3 points.
Another strategy, known as arbitrage, or an "arb" or "scalp", involves finding different moneylines for the same event. In this case, the bettor will bet the more favorable line at both books, and have a guaranteed profit. For example, if Book 1 considers Team A to be worth +200 (2 to 1 underdog), and Book 2 considers Team B to be worth +200, a bettor can bet Team A at Book 1, and Team B at Book 2, and guarantee a 100% profit. This is a no-risk bet, as the player is guaranteed a profit no matter the result of the game.
Many bookmakers now offer what are known as "exotic" bets, which are lines offered on non-traditional events. These include events like political races, talent contests (like American Idol), when characters will die in TV series, how many hurricanes will strike the coast of the United States in a season, and other strange bets.
Beyer, Andrew (Reissue edition (May 6, 1994)). Picking Winners : A Horseplayer's Guide. Houghton Mifflin. ISBN 0-395-70132-5.