betting on sport

Games and puzzles have always fascinated me. I enjoy figuring out solutions to complex problems, and I enjoy writing out those solutions. When I was about six years old, I learned the rules for tic tac toe. While my friends were drawing lines and marking their x's and o's, I was figuring out the optimal strategy. I figured out where to mark my x if I played first, If I played second, I figured out where to mark my o as a function of where my opponent placed an x. I never lost a game of tic tac toe.
When I was about twelve I started unlocking the secrets of blackjack. I used an office calculator (personal computers did not exist then) to working out the expectations - I removed the dealer's upcard and two player cards, and figured out what the player's expectation was for standing, hitting, or doubling down. Unfortunately, before I finished, Dr. Edward Thorp beat me to the punch with his book Beat the Dealer, the first book on card counting. The first thing I did when I got Thorp's book was examine the numbers in his tables 4a to 4j, which duplicated the work I had been doing. Thorp's numbers agreed with my own, so I knew that he was giving us the real goods. Some people doubted that blackjack could be beaten, but I was convinced that Thorp presented a winning system in his book. I learned his ten-count, and then had to wait until I turned twenty one so that I could use my new skill in Nevada.
The game keeps changing, so there is always need for a new book. When Thorp wrote his book, blackjack was dealt from a single deck, and about the only rule variation was whether the dealer stood or hit on soft seventeen. I still remember when four-deck blackjack came to Las Vegas -- it was like a whole new game. I needed four-deck strategy numbers and they did not exist in any of the blackjack books available at the time, so I worked out my own numbers on computers at college. I needed surrender numbers and they also were not available in books, so I worked out my own. I needed numbers for splitting pairs when you were not allowed to double after splitting, and so worked out my own. Thirteen years after Thorp's book appeared, I published a blackjack book of my own. I've since published a couple more books and software for analyzing blackjack, and have a website devoted primarily to blackjack
Then I figured out video poker, and wrote software analyzing it and then a book explaining the strategy generated by the software. I analyzed pai gow poker to come up with the optimal strategy for dividing a seven-card hand into two hands of five cards and two cards, and wrote a book on that game. I also wrote a book on betting horses. Along the way I played many casino tournaments, learning the details of tournament strategy by playing against the pros and developing a few ideas of my own. That also culminated in software and a book.
I've always been fascinated by sports betting. What fascinates me most is the mathematics of prop bets. Should I bet a team to have fewer than 8.5 season wins at -170, or should I take the same team to have fewer than 8 wins at -110? One of those bets is better than the other, and I enjoyed the process of figuring out which is the better one. My interest in sports betting culminated in a book titled Sharp Sports Betting, and this website.
In the summer of 2004, I turned over administration of SSB to a frequent poster (and current NFL host) who goes by "Goats" so that I could study the casino game of craps. A skillful shooter can get the edge in his favor. I wrote a book explaining how to build the necessary skill at tossing dice, and how to apply that skill in a casino, including what bets to make. I see my future as publishing books written by other people rather than writing another book of my own.

Sports betting is the general activity of predicting sports results by making a wager on the outcome of a sporting event. Perhaps more so than other forms of gambling, the legality and general acceptance of sports betting varies from nation to nation. In the United States, for example, sports gambling is only legal in Nevada casinos, while in many European nations bookmaking (the profession of accepting sports wagers) is highly regulated but not criminalized. Proponents of legalized sports betting generally regard it as a hobby for sports fans that increases their interest in particular sporting events, thus benefiting the leagues, teams and players they bet on through higher attendances and television audiences. Opponents fear that, over and above the general ramifications of gambling, it threatens the integrity of amateur and professional sport, the history of which includes numerous attempts by sports gamblers to fix matches, although proponents counter that legitimate bookmakers will invariably fight corruption just as fiercely as governing bodies and law enforcement do. Most sports bettors are overall losers as the bookmakers odds are fairly efficient. However, there are professional sports bettors that make a good income betting sports.
Aside from simple wagers--betting a friend that one's favorite baseball team will win its division, for instance, or buying a football "square" for the Super Bowl--sports betting is commonly done through a bookmaker. Legal sports bookmakers exist throughout the world (perhaps most notably in Las Vegas). In areas where sports betting is illegal, bettors usually make their sports wagers with illicit bookmakers (known colloquially as "bookies") and on the Internet, where thousands of online bookmakers accept wagers on sporting events around the world. (In the United States, the legality of Internet wagering is ambiguous, due to the fact that online bookmakers generally operate outside of the U.S. Some online bookmakers do not accept wagers from the U.S. due to these unresolved legal questions.) The bookmaker earns a commission or "vigorish" by regarding the money at risk as less than the size of the bet placed. A common line is a $110 bet on a fair coin which pays $210 to win and $0 to lose. On this line, it costs $220 to bet both sides of the same coin simultaneously, but the combined bet always pays $210. The $10 loss constitutes the vig. There are opposing positions on whether the winner or loser can be construed as paying the vig, but this debate is not especially meaningful. If you view $110 to win $210 on a fair coin as $100 at risk, then it will appear as if the loser pays the vig; if you view the same line as $110 at risk, then it will appear as if the winner pays the vig. It happens that standard practice among bookies is to adjust odds so the amount at risk remains constant from the winning side of the proposition, hence the common perception that the loser pays the vig. Vigs expressed as percentages suffer from the same perceptual bias. On the line as given in this example, for a fair coin, the bookie has an expectation of making $5 for each $110 bet placed, which is often divided out and expressed as 4.5% Odds on teams or opponents are quoted in terms of the favorite (the team that is expected to win, thus requiring a riskier wager) and the underdog.
Bookmakers generally offer two types of wagers on the winner of a sporting event: a straight-up or money line bet, or a point spread wager. Moneylines and straight-up prices are used to set odds on sports such as soccer, baseball and hockey (the scoring nature of which renders point spreads impractical) as well as individual vs. individual matches, like boxing. For these sports, bookmakers in Europe and Asia generally use straight-up odds, which are quoted based on a payout for a single bet unit; for example, a 2-1 favorite would be listed at a price of 1.50, whereas an underdog returning twice the amount wagered would be listed at a price of 3.00.
American bookmakers generally use moneylines, which are quoted in terms of the amount required to win $100 on a favorite, or the amount paid for a $100 bet on an underdog. The amount "won" in a bet is the net amount over and above the initial bet. If a person wins $200 on a bet of $100, the bookmaker actually pays the winner $300 (i.e. $200 plus the initial bet of $100).
For example, a baseball game between the St. Louis Cardinals and Chicago Cubs might have a moneyline on St. Louis (the favorite) at -200 and Chicago (the underdog) at +180. A bettor looking to take St. Louis must risk $200 for every $100 he wishes to win over and above the initial $200 bet. A person wagering on Chicago will win $180 for every $100 he bets.
The +180 moneyline on Chicago includes a 20 cent "dime line". Bookmakers generally use a "dime line" with moneylines to calculate the vigorish they receive on losing wagers. Without the 20 cent dimeline in the example above, the Chicago moneyline would be +200.
For favorites of -120 to -150, the difference between the favorite and underdog is 10 cents; i.e., the underdog to a -120 favorite is priced at +110. The discrepancy between prices rises for favorites of -160 or higher.
Unlike point spread bets, a moneyline wager requires only that the team wagered upon win the match. In sports such as baseball, where certain teams can be heavy favorites against weaker opponents (sometimes as much as -350 or higher), the moneyline system requires that a hefty sum be risked on the favorite, while enticing underdog players with a higher payout.
In sports such as basketball or American football, betting on the point spread is more popular, although money line odds are usually offered as well. A point spread wager typically requires a bettor to risk $110 to win $100, the extra $10 being the bookmaker's vigorish if the wager loses. However, bettors backing the favorite collect only if their team wins by more than a specific victory margin, which is set at the time of the wager. This is called "covering the spread". Similarly, underdog bettors can collect even when their team loses, as long as they win against the point spread by losing by fewer points than were quoted by the bookmaker. For example, suppose that a college football game between Kansas State and Kansas had K-State as a 27 point favorite (quoted as K-State -27, or Kansas +27):
If Kansas State defeats Kansas by more than 27 points, they have covered the spread and bettors on K-State would receive $100 on a $110 bet. Kansas bettors lose the $110 they wagered. If Kansas defeats K-State, bettors on Kansas would receive $100 on a $110 bet. K-State bettors lose the $110 they wagered. If Kansas loses by less than 27 points, they have won against the spread. Bettors on both sides are then treated exactly as if Kansas had won the game. If K-State wins by exactly 27 points, the wager is called a "push", and neither side wins. Standard practice by U.S. bookmakers is to return the stakes of all bettors on the game in full. To prevent pushes and ensure that they receive their commission on losing wagers, bookmakers often set point spreads that include a half-point. Another common wager available for sporting events involves predicting the combined total score between the competing teams in a game. Such wagers are known as "totals" or "over/unders." For example, the K-State/Kansas football game described above might have a total of 55 points. A bettor could wager that both teams will combine for over 55 points, and play the "over." Or, he could predict that the score will fall under this amount, and play the "under." As with point spreads, bookmakers frequently set the totals at a number involving a half-point (i.e., 55.5), to reduce the occurrence of pushes.