question: How do the odds on betting sites get calculated and re calculated during a game 24 Hours round the clock and how is it done to begin with?
comment: When someone bets on sports, the bookie in the old days would set odds, as usually one team is better than the other, so the bookie needs to keep things balanced. The bookie takes a commission on every bet, so he doesn't care which side wins. He does however need to make sure there is equal money on both sides of the wager, otherwise he'll have to make up the difference if there isn't enough money to pay out the winners. So he uses odds to balance that. He'll set odds and if he still sees too much money going onto one team, he'll change those odds. People will bet the underdog if the odds are right, because sometimes the underdog will win, and that will result in a huge payoff for them. 10:1, 20:1, 30:1 odds can be found sometimes. If you bet $100 and could win $3000 then that's an enticing risk for some people. For team sports it's usually a point spread, then Team A is much better than Team B, so team A will have -24 points and Team B will be +24 points. So whatever the final score is, you use that point spread as an adjustment and that will tell you who won the bets. Team A scores 50 and Team B scores 30, but Team B gets a 24 point bonus due to the point spread, so for the purposes of the bet, the final score was Team A 50 and Team B 54, so the people who bet on team B would win and team A betters would lose. If this wasn't in place 100% of the bets would go on team A and that isn't good for the bookie. As for how it's managed, I'm sure there are automatic programs that balance things on the website, as it's easy to track who is betting on which team and then make incremental changes in the betting line until things balance out. Back in the day with real live bookies, they would keep paper records which would enable them to track how many bets were going on each team. Most bookmakers were one man operations, so it was easy for them to maintain an overview since they were dealing with each bet personally.
passages: A multitude of websites also have been created and are updated regularly every after the morning, afternoon, and evening draws are recorded. Most of these websites also try to compile and pseudo-analyze results based on prevailing results and techniques used by bettors of the game- this even though results are drawn in random.
   Forecasts are bets on a single event that require the correct forecasting of the finishing order of (usually) the first two or three finishers in the event. Returns on correctly predicted finishing orders are calculated by industry sources via computer software that uses the starting price of all participants in the event, and are usually declared to a £1 stake unit on (mainly) horse and greyhound races.
  
  Section::::Forecasts.:Straight Forecast.
   Oddschecker is an odds comparison website, which compares the odds offered by the most popular betting companies that cater to British and Australian customers, including Sky Bet. It forms part of the betting content of some other sites, such as Bettingzone. The company also offers reviews and comparison of online gambling websites through its 'Casinochecker', 'Pokerchecker' and 'Bingochecker' sections.
  
  Oddschecker was established in 2001 and acquired by Sky in 2007.
  
  Section::::Soccer Saturday Super 6.
   Should a selection in one of these bets "not" win, then the remaining winners are treated as being a wholly successful bet on the next 'family member' down. For example, only two winners out of three in a Trixie means the bet is settled as a double; only four winners out of five in a Canadian means it is settled as a Yankee; only five winners out of eight in a Goliath means it is settled as a Canadian. The place part of each-way bets is calculated separately using reduced place odds. Thus, an each-way Super Heinz on seven horses with three winners and a further two placed horses is settled as a win Trixie and a place Canadian. Virtually all bookmakers use computer software for ease, speed and accuracy of calculation for the settling of multiples bets.
   The odds or amounts the bookmaker will pay are determined by the total amount that has been bet on all of the possible events. They reflect the balance of wagers on either side of the event, and include the deduction of a bookmaker's brokerage fee ("vig" or vigorish).
  
  Also, depending on how the betting is affected by jurisdiction, taxes may be involved for the bookmaker and/or the winning player. This may be taken into account when offering the odds and/or may reduce the amount won by a player.
  
  Section::::See also.
  
  BULLET::::- Odds ratio
  
  BULLET::::- Odds algorithm
  
  BULLET::::- Galton box
   In the days before software became available for use by bookmakers and those settling bets in Licensed Betting Offices (LBOs) this method was virtually "de rigueur" for saving time and avoiding the multiple repetitious calculations necessary in settling bets of the full cover type.
  
  Section::::Settling other types of winning bets.
  
  Up and down
  
  Round Robin
  
  A Round Robin with 3 winners is calculated as a Trixie plus three Up and Down bets with 2 winners in each.
   Bookmaker margin in English football leagues decreased in recent years. The study of six large bookmakers between 2005/06 season and 2017/2018 season showed that average margin in Premier League decreased from 9% to 4%, in English Football League Championship, English Football League One, and English Football League Two from 11% to 6%, and in National League from 11% to 8%.
  
  Section::::Overround on multiple bets.
   The bookmaker is known for offering odds on controversial markets in order to garner publicity, e.g., in November 2008, 16–1 was laid that United States President Barack Obama 'would not finish' his first term (this was widely interpreted as his odds of assassination).
   A combination forecast is a wager on three or more named selections in order to choose two of the selections to finish 1st and 2nd in the correct order in a specified event. It is the same as the number of straight forecasts on selections "a", "b" ... "n" given by the formula "n"("n" − 1) and therefore requires this number of unit stakes. E.g. 3 selections - 6 bets; 4 selections - 12 bets; 5 selections - 20 bets; etc. Equivalent to boxing an exacta/perfecta with more than two runners in North America.
  
  Section::::Forecasts.:Tricast.
   The odds quoted for a particular event may be fixed but are more likely to fluctuate in order to take account of the size of wagers placed by the bettors in the run-up to the actual event (e.g. a horse race). This article explains the mathematics of making a book in the (simpler) case of the former event. For the second method, see Parimutuel betting.
   The SBR websites main feature is its live betting tool. The SBR Odds betting tool provides bettors with live odds across 32 different sportsbooks. The tool also allows bettors to view the history of line movements, which is said to be helpful for professional bettors.
   With the advent of Internet and bet exchange betting, the possibility of fixed-odds arbitrage actions and Dutch books against bookmakers and exchanges has expanded significantly. Betting exchanges in particular act like a stock exchange, allowing the odds to be set in the course of trading between individual bettors, usually leading to quoted odds that are reasonably close to the "true odds."
  
  Section::::Calculating fixed odds.:"The best of it".
   The betting tool has a number of features that aid each bettor when comparing odds between different sportsbooks. Any changes to the odds are colour coded, which allows the bettor to compare sportsbooks against each other. Betting movement is essential to any professional bettor, giving them the option to view where money is being placed from the line opening is seen as one of the major components. Bettors can also view archived bets from the same day.
  
  Section::::Reception.
   In effect, the bet has been calculated as a Lucky 15 minus the singles. Note that the total returns value of £999.16 is a penny higher than the previously calculated value as this quicker method only involves rounding the "final" answer, and not rounding at each individual step.
  
  In algebraic terms the OM for the Yankee bet is given by:
   Prior to the event, betting agencies will often provide approximates for what will be paid out for a given outcome should no more bets be accepted at the current time. Using the wagers and commission rate above (14.25%), an approximates table in decimal odds and fractional odds would be:
  
  In real-life examples, such as horse racing, the pool size often extends into millions of dollars with many different types of outcomes (winning horses) and complex commission calculations.
   Ignoring any bonuses, a 50 pence each-way Lucky 63 (total stake £63) with 4 winners [2-1, 5-2, 7-2 (all odds a place) and 6-4 ( odds a place)] and a further placed horse [9-2 ( odds a place)] can be relatively easily calculated as follows:
  
  For the family of full cover bets that do not include singles an adjustment to the calculation is made to leave just the doubles, trebles and accumulators. Thus, a previously described winning £10 Yankee with winners at 1-3, 5-2, 6-4 and Evens has returns calculated by:
   A reversed forecast (RF) is a wager requiring the naming of two selections to finish 1st and 2nd in either order in a specified event. It is the same as two straight forecasts on selections "a" and "b": "a" 1st, "b" 2nd and "b" 1st, "a" 2nd. Requires two unit stakes. Equivalent to a "boxed" exacta/perfecta in North America, where the quinella is a similar wager that requires only one unit stake.
  
  Section::::Forecasts.:Combination Forecast.
   Punters placed bets with several bookmakers, and collected as usual when results came through. Everything seemed to be going to plan until another leading newspaper, "The Sporting Life", noticed that they had not been informed. 
  
  They did not want to be left out, so they copied the results 24 hours later, but there was a slight, but important, difference in the sets of results: one winning horse was given at 5-1 in the Sportsman, but at only 5-2 in the Sporting Life. 
   Within financial fixed odds betting the odds are fixed, while the strike price where a win is achieved relative the current level changes. The fixed odds company will calculate how much has to be bet to win a certain amount upon settlement if the conditions of the prediction become true.
  
  Section::::Binary betting.
   For example, before game 5 of the 2012 NBA Finals, the Miami Heat were expected to beat the Oklahoma City Thunder. The line read: Miami −3, Oklahoma City +3. To determine who wins against the spread, the line is either added or subtracted from a team's final score.
  
  In the above example, if the bettor chose Miami, he would subtract 3 points from Miami's final score and compare that to Oklahoma City's final score. If taking Oklahoma City, he will add 3 points to Oklahoma City's final score.
   Section::::Exchanges and traditional bookmakers compared.
  
  Most exchanges make their money by charging a commission which is calculated as a percentage of net winnings for each customer on each event, or "market." Gamblers whose betting activities have been restricted by bookmakers (normally for winning too much money) are able to place bets of unrestricted size as long as one or more opposing customers are willing to match their bets. The odds available on a betting exchange are usually better than those offered by bookmakers, in spite of the commission charged, because there are smaller overrounds.
   Glossary of bets offered by UK bookmakers
  
  This glossary of bets offered by UK bookmakers is a non-exhaustive list of traditional and popular bets offered by bookmakers in the United Kingdom. The 'multiple-selection' bets in particular are most often associated with horse racing selections but since the advent of fixed-odds betting on football matches some punters use these traditional combination bets for football selections as well.
  
  Section::::Forecasts.
   Most betting shops now offer free tea and coffee to attract punters. They usually have large televisions covering all the events, like an American sports bar. Until 1986 they were not allowed to have live broadcast coverage but the bookmaker often had a small portable television or transistor radio hidden behind the counter. Because punters could not see or hear live coverage, some bookmakers deceived punters by claiming a different result from the actual one, or could otherwise alter the declared starting price. This changed in 1986 and Satellite Information Services was formed to screen live races to betting shops. Greyhound races are now timed to the second on the feed pictures, since a scam that intercepted and slightly delayed the broadcast feed for greyhound races, which typically last less than two minutes. By delaying the feed slightly, an accomplice on-course could communicate by telephone with one in a betting shop off-course who had already seen the result, and thus bet on a racing certainty.
   The website is used by a number of gambling websites to incorporate live odds into their website through a RSS Feed. As an example of this, The Sports Lifestyle uses this system to display an NHL Scoreboard throughout their website. The websites odds and picks regularly referred to online. The websites picks and odds have featured in the Seattle Times, Huffington Post, and the Bleacher Report.
  
  SBR Odds are also known within the betting industry as a credible resource website.
  
  Section::::Mechanics.
   A tricast is a wager requiring the choosing of three named selections "a", "b" and "c" to finish 1st, 2nd and 3rd in the correct order in a specified event. Requires a single unit stake. Accepted on horse races where 8 or more horses are declared and at least 6 run, and on greyhound races of 5 or more runners that form part of the bookmakers' main service. In North America, this wager is known as the trifecta (USA) or "triactor" (Canada).
  
  Section::::Forecasts.:Combination Tricast.
  