Flat betting in Baseball....

Whenever you make a betting decision it's based on your predicted line. If your line shows that you have a negative or small positive edge you don't bet. With a bigger edge you flatbet one unit and with an even greater edge you flatbet 1.5 units.
So both Kelly and flatbetting is depending on estimating the edge.

A problem with flatbetting is exactly that it is flat, that is, that all bets are weigthed the same.
Say you have two different games with the same line +200.
You have estimated an edge of 6% and 20% on these two games, so therefore you flatbet 1.5 units on both games.
Even if you are not able to predict your edge consistently, clearly it's profitable to weight the last bet more than the first.
You are actually doing it when you use 1.5 units instead of one unit.

guilty as charged.

Kev -

I have written what amounts to volumes over the years here on this - but I doubt it is still around or in one place or searchable - so I will explain what I do at a very high level and then ask for details and I will respond.....

At the highest level, I make more money in MLB from line buying and selling - and from arbitrage - than I do from actual bets that settle.  More detail on my process....

1.  I set lines that are predictive of results.  That means that I dont set lines as to what I think the line will be - but I try to come up with predictive models to predict RESULTS.  This is often different than the real bettable line for a number of reasons.

2.  I take my lines, and compare them to the real lines.

3.  I have a predetermined set of thresholds that I bet based on the differences in the lines.  For instance, if there is a difference of 7 to 15 cents I bet one unit, 16 to 24 is 1.5 units, and 25 and up 2 units.   (Just an example).

4.  As lines move throughout the day, I buy and and sell as the betable line moves in and out of my thresholds.  So in the example above, I might bet a team that I have a 18 cent difference on for 1.5 units.  The line moves throughout the day, and now there is a 10 cent difference.  I would sell ,5 unit and profit the difference, while keeping the 1 unit as a bet.  Then if that line moves to 6 cents difference, I would sell the whole thing.  The same is for betting more if it moves the other way.

The key to this is setting good predictive lines, having accurate thresholds, and having a shitload of outs to get the best price available at any time.

I also do straight arbs too, but those are less and less.  Sometimes they sit out there, but not too often.

So in a typical day, I wont end up with a big portion of the bets I made originally come the first pitch.  I have often sold them, and I stick to this process no matter what - I never hold a bet because "I like it" - I always sell or buy more when I pass through a threshold.

Any quesitons, ask away.

interesting stuff guys

I have better success backing favourites than dogs but limit my number of bets

my staking system is as follows:

I write down 2000

my 1st bet is 20% = 400 which I deduct from the 2000 leaving 1600

suppose I collect 700 then I add this to the 1600 leaving 2300

my next bet is 20% = 460 which again I deduct from the 2300 leaving 1840

suppose it loses then my next bet (20%) is 368 and so on

if 20% of my progressive total results in an outlay that would leave the progressive total less than 1000 my bet is reduced to leave progressive total at 1000. eg progressive total 1180 (20% = 236) my bet is 180

as soon as my progressive total reaches 3000 or more I start again at 2000

as soon as it reaches 1000 I start again at 2000

obviously I can only have 1 bet running at a time (a plus IMO),,,,,,I'm betting larger when winning, less when losing

I aim to win 3 of 5 "sets" to leave a profit of 1000+ every 5 sets

each to his own - this works for me 

1.  Example:  My line is -150, the line opens at -140.  I bet 1 unit on the favorite.  Now the line moves against my line, going to -134 (crossing a threshold) so I bet another half unit.  Then if the line goes back up to -140, I sell the half unit because it crossed back over the threshold.

2.  I use Matchbook a lot.  Pinnacle also will have 6 cent lines this year, which will make MB lines move more, which is good for me.

3.  It depends on how you define ROI.  There really isnt an "investment" when you cant lose money on a wager.  When I buy at -140, and sell at +145, how do you calculate or define ROI?  Your investment (amount you can lose) is zero.  Im not really sure how to give you an answer.

Care to explain?

Van, you must spend an inordinate amount of time in front of the computer, No ? Your eyes have to hurt come July. Of course, you've been doing this along time and have probably figured out the time of day when the most activity occurs.

So are you saying that because Pinny is offering 6 cent lines, they may take on some customers that would otherwise be playing @ MB? And if so, I understand the lines moving more at MB because of this, however, do you think it will be harder to get large offers matched?

I do spend a shitload of time in front of the computer in April, May, June and July.  I am usually done by July.  But it is not fun.

What I mean by the lines moving more at MB because of the 6 cent spread at pinny.....

MB almost always has both teams within the spread at pinny - it is rare to see the lines at MB outside of the lines at Pinny offering a straight up arb.  So MB lines when it was 8 or 10 cents didnt necessarily move when pinny moved up or down a penny or two, but they will have to move more often now that pinnys spread is smaller.  For instance - if Pinny had a 3 cent spread MB would move with every pinny move.

As far as liquidity, we will have to wait and see.  My OPINION is that MB is THE book for MLB, and everyone knows it - and there will be 1 cent lines with lots of liquidity.  But we will see.

Actually, what you are doing is making every game exactly the same weight.  Flat betting is when all games have equal value.  When you do it the way I suggest, you accomplish this.

If you dont do as I suggest - your big favs and big dogs always have more importance than your smalll favs and small dogs - not what is commonly defined as flat betting.

van-

Can I ask you how much volume you "trade" (money-wise) in what you might consider a typical day in baseball.