Originally Posted by ~primetime~
the odds are determined by the gamblers themselves...and will change over the week...(not by much usually)
the casinoes try to get an even 50/50 of the money on each side of the bet, and then charge the winner "juice"...which is like 5%-15% of the winnings usually...
so basically, the point spread reflects what the entire gambling world thinks...
Check this out...
Rising Star Sports NFL Record
NFL Past 18 Years:
The theory of getting balanced action and pocketing the vig (juice) is always the goal of the Oddsmakers; but, in the real world this rarely happens. On a typical 15 game NFL weekend, the major sports books will be in balance on 8 to 9 games with a 5% risk free return. One or two games may have major imbalance, which will cause the game to go off the board early in the week and reopen on game day as a circled game (limit on the wager amount) to reduce their risk. On the remaining 4 to 5 games they will be at risk $50,000 to $100,000 on each match up. On these 4 or 5 at risk games is where you will find Rising Star's recommended plays. This is also where Las Vegas turns the weekend into a Fantastic week for the sports book. To the sports book they could care less who wins the balanced games as they will take 5% of the total amount wagered no matter which team wins against the spread (ATS).
On the circled games they don't win much and they don't lose much as they have limited the amount wagered. If they win all of the 4 or 5 at risk games, their return is in excess of 9% of the total handle for the weekend. Over the past eighteen years Las Vegas and Rising Star have won between 60% and 66% of these at risk games and that is why both of us are still in business.
Look at their success rate in the link. (at the bottom)