I have 3 questions about line movement.
First question..in baseball, is most of the ML movement related to the release of the rosters? Or is it simply that the books release sometimes a wildly incorrect line? Because daily many games move A LOT.
2nd question, why do people arb out of a good line position? When you do this, you are simply taking the market shaped line. It guarantees profit today but in the long run I would think this would definitely lower your profit because you are combining a +EV bet (the original bet when you beat the line movement) with usually a -EV bet that the market has corrected and vig is there too. Why not just keep the +EV bet? This seems like the same concept as trying to middle your original position in a football game at halftime (with a bet on the 2nd half) when you are winning your original bet handily. The middle bet at half should be looked at for what it is, a completely seperate bet and should be judged on its own, not for how much of a "middle" it gives you between it (halftime line) and game line you are already winning. Unless the halftime bet is +EV I was told it should be avoided. Which makes perfect sense.
Yet people arb out of good line bets (both bets made pre game in baseball) and it is considered a good move. Why? What is the difference between this and the football game scenario I gave above. Shouldn't the second bet be judged for its EV alone?
I was told by a smart guy here that beating the closing line by a few cents will make you a long term winner by itself. Which brings me to my 3rd question......
At what point in each of the major 3 sports is beating the closing line a long term profitable venture? At what point with beating the closing line in each of the big 3 sports are you going to be able to simply bet that line with no capping and win long term?