Why Lines Open Where They Do.

[Seanie Mac]

Why Lines Open Exactly Where They Do

by Ted Sevransky
Lines open where they do for a reason, not by chance. Sportsbooks are designed to make a profit, not to provide a service. The reason so many new offshore books have opened over the past few years (several hundred, at least) is because they are making money for their owners. More people lose at sportsbetting than win; that is why offshores offer sign-up bonuses and other promotions to entice new clients.
Much of the research that Bookmakers use to formulate an opening line comes from a single company - Las Vegas Sports Consultants, Roxy Roxborough's former outfit (he's retired now). What LVSC does is analyze all the factors that go into a particular game. They begin with power ratings, a computerized assessment of both teams' relative talent. They factor in home field advantage and possible weather conditions. LVSC then considers the actual matchups between positions - how do the defensive backs match up against the wide receivers or the offensive line vs. the defensive line. Next they will examine the situational factors - how the teams will respond coming off various types of wins or losses, look-ahead situations or revenge games, or any other motivational (i.e. not number-crunching) factors. Lastly, they access how the bettors have responded to the teams in previous games - which side is likely to take money, and how much of a differential do they expect. In short, they handicap the games as well or better than most mortals can -- just to come up with this opening number.
Each book then takes LVSC's analysis and opening numbers and adjusts it to their particular clientele. Some books cater mostly to large "wiseguy" players. Others take most of their money in $20 or $50 chunks from the general public. Still others take money from bookies laying off unequal action around the country or from particular regions. And many take bets from all of the above. This is why there is some variation (rarely more than a point) between the virgin numbers from different sportsbooks.
In all sports EXCEPT the NFL, virgin lines are set to beat the wiseguys, not the public. It takes one hundred $100 bettors to equal the influence of a single maximum limit bet. So the "square" bettor (meaning the average Joe Schmo) really doesn't have that much influence over where an opening line is set - the books have bigger fish to fry. Professional football is the public's domain. There are enough small bettors to offset the big $$ that comes in from the syndicates and wiseguys. This is because there are relatively few games AND one heck of a lot of bettors.
Every line opens at a particular number for a reason. This fact cannot be emphasized enough!! There are no accidents and few mistakes (although mistakes occasionally do occur). Our job as handicappers is to figure out why the lines opened where they did, and what it means for that particular matchup.
One theory I have developed for analyzing virgin lines I call the " � point off key number theory" (nice name, huh). THEORY - When the line opens at 1/2 point off of a key, the house is trying to subtly influence a position among bettors. Key numbers in football include: 1, 3, 7, 10, 14, 17, 21 etc, etc. These numbers are "key" because the scoring systems of touchdowns and field goals means that the final score will have a margin of victory by one of these scores more often than not. As a bettor, wouldn't you rather be taking 7 � points instead of 6 � , or laying 2 � instead of 3 � ? Of course you would. However, past evidence has shown rather clearly that the opposite is true. Teams that open at -7.5 cover far more often than teams that open at -6.5. Why? Because a team laying more than a touchdown is supposed to be laying more than a TD, and a team laying less than 7 is supposed to be laying less than 7. Remember: a line opens at -1 instead of pick 'em for a reason!!
In basketball, there are no key numbers like football, since the scoring comes only in 1's, 2's or 3's. But psychologically, people are still influenced by some key numbers: 4 � vs. 5 �; 9 � vs. 10 �, 14 � vs. 15 � etc. Again, I look towards the side that appears to have the worst of it - I would rather lay 10 � than 9 � . Totals work much the same way - I look to bet under a virgin total of 189.5 and over on a total of 190.5
This theory is just that: a theory, not a certainty. I use it to absolutely eliminate some sides, and to reconsider others. If there is a side that I like to begin with, and the number comes out in my favor, it is then that much closer to being a play. An opening line � point off a key number is a valuable tool in the handicappers arsenal, but it no single factor makes a particular side an automatic play.
Courtesy of http://www.whocovers.com
__________________

[Seanie Mac]

took this off another forum but I thought it was a great read so I wanted to share.

[Seanie Mac]

this will explain why books open -1 -117 and stay there, mostly sharp books, pinnacle, Legends, etc


Advanced Betting Concepts
Wong Teasers, so named for the sports bettor Stanford Wong who wrote about them in his book Sharp Sports Betting, comprise a sports betting system that does not require any handicapping skill to be profitable.* That's why we like them!
A teaser bet is a combination bet in which multiple single bets are combined on a ticket for a common result.* If you take a two-team teaser you select two spread bets and if both win you are typically paid -110 for your bet.* The tease is that you get to add some points to your spread for both bets.* In NFL betting a standard amount to add is 6 points.* The remainder of this article will presume we are discussing 6-point NFL teasers.
For example, if you were considering the following bets:
San Diego vs Los Angeles:* Los Angeles +2
Detroit vs Minnesota: Detroit -7.5
You can tease those bets and take Los Angeles +8 and Detroit -1.5, with a combined payout of -110 if both legs of your bet win.* You increase your odds of winning by adding points but decrease your payout odds.
Breaking Down Teaser Strategy.
In order to break even on -110 bets, you must win 52.38% of the time.* This means that to win your two-team teaser you must win both legs 52.38% of the time.* To do that you must win each leg 72.37% of the time.* (72.37%)*(72.37%) = 52.38%
If your leg is offered at -110 as a straight spread bet you would need to find opportunities where adding 6 points to the spread increases the probability of winning by more that 20 % (72.37% - 52.38%).* If adding 6 points does not add 20% to your winning probability then you are better off just straight betting the legs individually and not playing the teaser.
Wong Teasers are those teasers where there is > 20% added to the win probability when the 6 points are added.* Simply stated, they occur in the NFL where the favorite is favored by 7.5 to 8.5, or when the dog is getting +1.5 to +2.5.* Why?
When the favorite is giving up -7.5 to -8.5 and you can add 6, the range is now -1.5 to -2.5.* You have crossed over the 3 and the 7.* Those are key numbers in NFL spreads, as they occur with a very high frequency.
Similarly, if you take the dog at +1.5 to +2.5 adding the 6 points gives you +7.5 to +8.5.* This gets you over the 3 and the 7.
Getting over both the 7 and 3 adds roughly 25% to your win probability on a single NFL spread bet.* This gives you the favorable odds to play the teasers profitably without having to handicap the games.

[Seanie Mac]

in week 1, if you followed the Wong Teaser system, you would have won every possible combination. Never do this in college football. College teasers are generally -EV because the market is not as tight as the NFL with the amount of teams and lesser teams.


Cleveland
Pitt
Baltimore
Houston
Buffalo
Seattle
Philadelphia
You could have even done Chicago


Essentially you want to be able to cross 3 and 7, and win if those numbers were to hit

[Sweetleaf22]

Originally Posted by Seanie Mac

Getting over both the 7 and 3 adds roughly 25% to your win probability on a single NFL spread bet.* This gives you the favorable odds to play the teasers profitably without having to handicap the games.

[Bobtheicon]

I like the Wong info. Good info here.

[Bobtheicon]

Denver fit into the Wong as well with a winner.

[Seanie Mac]

Originally Posted by Bobtheicon

Denver fit into the Wong as well with a winner.

forgot about them


now obviously they won't always win everytime but Wong killed books doing this.

[Bobtheicon]

Yeah. Tough part is picking the combinations. There are probably a lot of games each week to choose from. Wouldn't want to play every possible 2-team teaser that fit into the Wong.

(I like saying "fit into the Wong")

[bigsportsguy2006]

wow, interesting seanie ... just a side comment as well ... since they say you need to increase your odds to 72.37% for each bet that you tease, that is essentially the equivalent of a -262 favorite for those that were curious. (i.e. a parlay with a -262 favorite, and another -262 favorite is equivalent to a -110 wager)

[bigsportsguy2006]

hey seanie, hate to jack this thread but also had a follow question for you from yesterday ...

here is what you said: correlated parlays are when it's like the spread is 40% of the total. books won't take them because it's just mathematical sense for fav and over, dog and under

here is what i said:
i guess my question is 40% really the percentage? or is it higher? thats what i was trying to figure out. thanks for all help

just curious .. is 40% really the right number for these? i figured it wuold be higher, but maybe not? i mean, that says a 21 point underdog with a total of 50 would be a play since it is 42%? i think it would be much more attractive another 60%

[Seanie Mac]

if you can make sense of this, it's an example of how some do it

Bankroll	100000	Dog	Fav	Rotation	Rotation	Spread	Teased line		Teams	Payout - dec odds	Constraints
Kelly Fraction	1										
Cleve	TB	463	464	3	9		 * *3.0	2.8	None
Pitt	Atl	458	457	1	7		 * *4.0	4	None
Det	Chi	459	460	-6.5	-0.5		 * *5.0	6	< = 100
Balt	Nyj	479	480	2	8		 * *6.0	8	None
Hous	Ind	468	467	1	7				
Phill	GB	472	471	3	9				
Seatt	SF	474	473	3	9				
Teaser #							Odds	Bet	% of roll
1	463	460	472				 * *1.8	 *445	0.004%
2	463	479	472				 * *1.8	4,131	0.041%
3	460	479	472				 * *1.8	2,958	0.030%
4	463	458	460	479	468		 * *6.0	 *100	0.001%
5	463	458	460	479	472		 * *6.0	 *100	0.001%
6	463	458	460	479	474		 * *6.0	 *100	0.001%
7	463	458	460	468	472		 * *6.0	 *100	0.001%
8	463	458	460	472	474		 * *6.0	 *100	0.001%
9	463	458	479	468	472		 * *6.0	 *100	0.001%
10	463	458	479	468	474		 * *6.0	 * *3	0.000%
11	463	458	479	472	474		 * *6.0	 *100	0.001%
12	463	458	468	472	474		 * *6.0	 *100	0.001%
13	463	460	479	468	472		 * *6.0	 *100	0.001%
14	463	460	479	468	474		 * *6.0	 *100	0.001%
15	463	460	479	472	474		 * *6.0	 *100	0.001%
16	463	460	468	472	474		 * *6.0	 *100	0.001%
17	463	479	468	472	474		 * *6.0	 *100	0.001%
18	458	460	479	468	472		 * *6.0	 *100	0.001%
19	458	460	479	472	474		 * *6.0	 *100	0.001%
20	458	460	468	472	474		 * *6.0	 *100	0.001%
21	458	479	468	472	474		 * *6.0	 *100	0.001%
22	460	479	468	472	474		 * *6.0	 *100	0.001%
0.093%
Odds of + $$		0.4%

[Seanie Mac]

Originally Posted by bigsportsguy2006

hey seanie, hate to jack this thread but also had a follow question for you from yesterday ...

here is what you said: correlated parlays are when it's like the spread is 40% of the total. books won't take them because it's just mathematical sense for fav and over, dog and under

here is what i said:
i guess my question is 40% really the percentage? or is it higher? thats what i was trying to figure out. thanks for all help

just curious .. is 40% really the right number for these? i figured it wuold be higher, but maybe not? i mean, that says a 21 point underdog with a total of 50 would be a play since it is 42%? i think it would be much more attractive another 60%

I don't know the exact %, if there really is one. I think I have seen 40% posted somewhere before, but even 30% seems high.

[QuadzillaXXX]

i actually have stanford wong's book but haven't really read it, guess i should have

[ParrotHead]

Is the book outdated or does it focus more on the math basis of sportsbetting? What Im asking is should I read Wongs book