Unbelievable Line Moves

[TheGambler]

Okay guys, as you are starting to notice, I am definitely a rookie when it comes to all of this sports betting. I'm 32 years old and I grew up watching football with my dad every saturday and Sunday and all I really know is betting through a local bookie. Since doing the online thing for 6 months now, I still have a lot of questions. I just wanted to let everyone know that as I will probably keep asking a lot of dumb questions. Here goes the first one:

What in the world can make a line move from -120 to +120 in a matter of seconds? I didn't think it was possible for that much money to be dumped at one time to move the line that much. However, in the last couple of days, I was getting ready to make a wager on baseball over/under. I no more typed in 1,000 on the over at +110 and it suddenly went to -110. I went to SBR Odds and every damn book was changing to -110. The same thing happened tonight when I was getting ready to bet on the Det/Boston over/under and it changed by 30 points. I'm sure there is a good explanation but I am very curious how this happens and why every book out there is aware of it at the same time. Please help!!

[nosttrader]

TheGambler,

Generally a large line move is either pitcher change, or in your case I think the total run was changed. for example before over 8 was -120, then they change the run line to 8.5 on +100. Ect. Hope this helps

Nosttrader

[rm18]

a lot of moves are "air moves" with smaller books just following the larger books without neccessarily taking a lot of action on the previous line. Also in baseball in could be some type of weather, or a key hitter being rested that moves the total quickly

[JoshW]

If a syndicate bets into enough key don best books that will cause pretty much the rest to move even if they don't get bet in to. So you can either have a true move were a syndicate (group of bettors) is trying to get down as much as possible or they could be hitting some key Don Best books and other follow. Either way steam chasers will often follow these moves (usually for arbitrage reasons) and they will bet into the slower books. The biggest moves are caused by established syndicates who get down a lot of money and/or are respected enough to have followers.