Setting the line: is it all about traps, tricks and public opinion?

[BigGamesOnly]

I heard once that a line is set so that the book gets even action on either side of the line to guarantee a profit through the vig. Then I heard that sometimes the books set lines to get the public deliberately on one side that will lose.

So I would think that a successful bettor would simply have to decide why a line was set at a particular number and bet accordingly. But it seems that it should be more complex than that.

What criteria do books use in setting a line?

 

[Oren1]

must be a secret.

 

[mhk]

Lines are all about equal action, period.. Books don't want to be one sided, thats why the lines move when they are one sided.. All books have a percentage (of money out on a side) on which the line will move.. They don't want to move too much, they might get middled, so they can have one sided action, but too much and it will move..

 

[jimmymo]

Books are in business to make money -- a wise person once told me that opening lines have more to do with psychology of marketing and consumer behavior than anyone can ever imagine...The theory that books only want equal action on each side is subject to major debate -- they know more about every match-up that almost every capper out there -- why shoudn't they use that info to beat the public senseless...

Here is a good piece on opening numbers...

http://www.whocovers.com/showarticle.php?article=14

 

[JohnnyDetroit]

mhk,

that is not 100% true. i believe maxim had a thing on line moves and the spoke with the head linesmaker from MGM Grand. He said that the equal action is not always true for the most part. if they have sharp action on one side they will not move just because more money (public money) is on the other side. also, shops like Pinnacle and other sharp sides obviously take stands on games.

 

[mhk]

I did make it sound like a law JohnnyDetroit.. Didn't mean too, but I know every book works on a certain % to move a line. It may be a different % at every book (which is also tied into money bet in all other games). In other words, not every week has 7.14% of bets on each game evenly split (assuming a 14 game nfl week).When a side starts getting close to 5% or so, it starts getting a little problematic for them. Of course the book can make a stand at any time, its just not in their best long term interest.

 

[ATX]

in the NFL, right around week 4 or so the lines are set by the numbers. sharp books then shade by the sharp action that is bet into them, and by the volume of public money etc. it's not an exact science, and just like us they have opinions which differ by scenario.

 

[ATX]

perception also plays a key part of this.

when they can get away with hanging a number that is a couple points off even across a key number b/c the public will still take it...

they will, and they did with SEA and the 44.

several other favorites still covered today even though the line was off fwiw.

 

[BigGamesOnly]

If lines are about equal action, it would seem to me that a person would be able to take advantage of that. Let me give an example.

Say, this weekend that the book thinks Oklahoma and Missouri will score 70 points. If they hang that total they believe they will get mostly action on the UNDER. So they hang 57.5 getting equal action on both sides. Then they inch it up to 60.0 scaring the squares off the OVER.

The smart person would know that even at 60 this line is too low and would be able to make some cash.

Is this scenario a valid one?