Indepth analysis of how chasing CAN work

On this forum there has been a LOT of debate over if chasing "works" or not.  You have doubters (DJ Destroyer and others) and believers (Neilsy, Rizz and others).  I almost weighed on this topic a few months back but was too busy at the time to sit down and write a post.  It's come up again in kreatture's thread so I thought it might be a good time to address the issue.

Chasing has and will continue to kill many bankrolls.  This is why DJ calls it "fatalistic" all the time.  He's being a little over dramatic with his semantics...but he is right...sort of.  If you don't understand what you are getting into, you're doomed to fail for sure.  It takes BIG BALLS to chase...many think they are ready, but few really are.  However...if you understand the math and have a statistical advantage entering a chase, you WILL succeed.

Allow me to make a not so quick illustration.  This will start very basic but makes a point at the end:


We all know that if you're betting a normal -110 vig that you must win 52.38% of the time to break even.  This is given by the simple equation:

breakeven% = y/(1+y)

Where y= the decimal odds (1.1 in this case...or 110/100)

Well, that doesn't sound too daunting...it's just over half the time you have to be right!  Ha...we have all learned how tough it is to do that.  However, it doesn't stop us from trying...there are a lot of reasons for this, but part of it is simply that 52.38% doesn't "sound" like a tall order.  Before we get too far into breakeven percentages...let's talk a little probability for a second.

Lets use the traditional tool for probability, the coin flip, since everybody can understand it's beautiful 50/50 probability.  We decide to adopt a "tails never fails" approach and make that our desired outcome.  You flip a coin...there is a 50% chance you will be right.  Let's pretend I decide to bet on a coinflip and the odds I'm given are to risk $1 to win $1.  I'm a gambling man and I like those odds.  My breakeven percentage is just 50%...exactly equal to the probability of each outcome.  With a little luck and a small run, I may win a few bucks.  I have the same odds to win as the house does.  But that's why God created the vig.  Now they tell me that I have to risk $1.10 to win $1.  Well, this just became a bad bet for me and tipped the odds in their favor.  Now I need win 52.38% of the time to break even but I only have a 50% chance of getting my desired outcome of tails.  This just became a bad bet...but as a gamblers, sometimes we think we can overcome the odds and come out on top.

Nothing about that previous paragraph is surprising...but for some reason, when probability or vig changes, people seem to forget that the same simple principles apply.  Most importantly, as probabilty and vig change, so does your breakeven percentage.  Just going from -110 to -130 raises your break even percentage to 56.52% (using same equation as earlier).  What chasing does, however...is it changes your probability.  This has a HUGE effect on break even percentage.  In addition, with MLB...the vig is a factor as well.

**********post was too long had to break it in half***************

*******part 2**********


A chase is simply betting on two (or more) outcomes instead of one.  Let's start with two to keep things simple.  Calculating the probability of two succesive events occuring is very easy...you learned this in 3rd grade:  you multiply the probability of the two independent events happening.  When flipping a coin, there is a there is a 50% chance of heads, so the probability of two heads in a row is 0.5 x 0.5 = 25%.  Very simple.  That means that if we love to gamble (and we do!) that if we want tails to come we have a 75% chance of that happening once every 2 flips.  Now the chaser is getting excited...75% chance of something happening sounds a lot better than a 50% chance, doesn't it??  Well, it will cost you to get that 75% chance.  If the vig is still -110 to bet on those two events, now your break even percentage changes dramatically.  It jumps to 77.32% (not going to write out the equation).  If you have a breakeven percentage of 77.32 but a probable outcome of 75%...it doesn't take math skills to know that's a bad bet... just like betting on one flip and having breakeven percentage of 52.38% was a bad bet.  Nothing has changed except that a 75% chance of winning sounds a lot better than a 50% chance of winning.

Well, let's take the example one step further.  We do some simple math and realize that if we chase for three straight coinflips, tails has a 87.5% chance of coming up (1-(0.5x0.5x0.5)).  Wow...87.5% chance of a win sounds great!!  Hold your horses though...our break even percentage has now jumped to an astounding 89.2% (not gonna write out the equation).  We are still making a losing bet, even though 87.5% sounds so good.  People get enticed by these numbers but you see mathematically, it's not a winning bet.  You need to raise you probability of winning to atleast 89.2% to even have a chance.

Ahhhh...but there is more.  You forgot about the vig.  In MLB...it's a huge factor.  If your vig changes from an average of -110 to an average of -140 (quite possible as many chase systems in MLB tend to lean towards favorites), your break even percentage for a 3 game chase jumps to 92.77%.

I think the point is becoming clear now.  For just a 3 game chase in MLB, with an average line of -110, you need to find a system that hits over 90%.  Not easy.  For a 6 game chase, the break even percentage for an average of -110 odds is 98.82%!!!  You have to be damn near perfect in that case or you WILL lose.  If you find a system that hit's at 99%, then you have a mathematical chance.  This is part of the reason I would never do a 6 game chase...because DJ is right about those...it's not a certainty, but the odds are VERY high that you will eventually get wiped out.  What's more is that the deeper you decide to chase, the more you put on the line.  Would you rather your chances of losing be 10.8% with 8.29 units on the line (3 gm chase at -110), or your chances of losing be 1.2% with 83.44 units on the line (6 gm chase at -110)??  The answer to that question lies in the hands of the individual of course...but for most long term gamblers, no bet is worth risking 83.44 units.

If you're going to chase, the best strategy is to identify a system that will give you a better probability of winning than the break even percentage.  It's not impossible but it can definitely be done.  If you find this situation you can exploit it quite well...especially in a sport like MLB where you have such a large number of games.

Another way to beat the chase odds is with different money management strategies.  The numbers I've shown above are for a straight martingale chase.  Using labby, or other MM can tip the scales in your favor as they change your break even percentage.  It's difficult to identify these and find one that works, but quite contrary to what some may think, it CAN be done...it is just extremely difficult.

Chasing is not for everybody, but mathmetically, it can definitely work.  If you are chasing deep, you can quickly end up with more units on the line than you're comfortable with.  Even in a short chase, unit swings can be large and this is often viewed is a negative for the long term.  Personally, I believe if you have some solid numbers, that is, if your probability of winning is higher than the break even percentage, then there is no doubt that a chase CAN be profitable and with a good money management strategy, you won't wipe out your bankroll in the process.

Leprechaun

IF YOUR PROBABILITY IS HIGHER THAN BREAK EVEN PERCENTAGE, THERE IS NO NEED TO CHASE. GOOD ARTICLE LEP!

I am running two chase systems for MLB. Worked well last season. I might start a thread next week, depending on some other things in my life.

Interesting read, thanks for sharing your insight.

I don't really want to get into it because I've shown the proof in many other threads but the facts remain: if you have an edge over the house, you don't need to chase as it just adds unnecessary risk. If you don't have an edge, chasing only compounds the problem.

There was a time once when I thought chasing was the way to go, but some smarter people showed me that I was wrong. If you fancy yourself intelligent and/or a serious sports investor (not trying to sound condescending) and you think chasing works then just keep reading until you think otherwise.

If you look in the right places and talk to the right people, it won't take long to negate chasing theories but don't stop reading until you no longer believe in them. Again, I'm not trying to sound condescending but the laws of mathematics show that chasing is fatalistic... and that's not semantics, that's life.

chasing works in some casino games.  but i have not found it to be successful in sports betting. 

 

the one guy on another site.  where he handicapped (a pro guy) went undefeated. he chased his picks 7 games .that proly works.

 

a blend of handicapping and chase.

 

7 bets  at 10 bux to win. was around 1280. if u lost ur 7th game.

lol

 

most chases should have a term on them. at ur 4th bet or possibly 5th bet.

possibly 6th bet depending on the game. (casino) and the initial amount wagered. and the house limits.

yeah. i just checked that guy is stil undefeated. amazing.

DJ...thanks for replying.  I appreciate the input.

You made me realize that I forgot to add something in my original post.  Chasing is not some sort of holy grail...nor is it necessarily the "way to go" as you put it.  It's just an option, that's all.  No one should use any given tool as an exclusive method to choose games, play a system, or as a money management strategy.  My aim was to show that if you look at the numbers, chasing can indeed work.  I was not trying to advocate it OR denounce it.  There have been situations where I've chased and other times when it didn't fit my approach.  The point is that if anyone chooses to use this strategy, they should be aware of what they are getting into.  I was hoping to show people that while chasing can work, if you need something to occur over 90% of the time, you're probably barking up the wrong tree.

I also forgot to mention something else...looking for an edge is only part of the reason a strategy may or may not work.  The chances are pretty small that you'll actually find a way to have a bet that has a higher probability of hitting than your break even percentage.  Most of the time, we try to make that gap as small as possible.  I hope people saw in my example that adding successive events to increase probability and therefore, shrink your gap, can be extremely dangerous if you don't understand what you're getting into as losses have an exponential effect.

You state that if you have an edge on the house that chasing only introduces unnecessary risk.  This can't be true if the number of successive events being analyzed are what give you the edge in the first place.  Of course, if you can find an edge without needing a series of a events, that's obviously preferable.  With each successive event, risk definitely goes up, but as I said in my original post...the desire to deal with that is completely up to the individual.  Some people have the stones and don't mind the volatility.  It has nothing to do with chasing, but that's why you have poker guys like Gus Hansen that succeed.  He likes the risk.  There are a lot of guys like that.  It might be frustrating when they win sometimes but it doesn't make them wrong...they just have less aversion to risk than the average Joe.

It doesn't take Ph.D in mathematics to understand anything about the laws of probability.  There's nothing in my original post that anybody with a highschool education couldn't understand or figure out.  We don't need to seek out mathematical genuises...let's use our collective intelligence to get it all straight right here.  If you have a true mathmetical example of why chasing can't work as a thoery then please post it here, because I have yet to see you show any examples.  That's the purpose of this forum and this thread...to share information and try to learn from others.  I'm human as the next guy, and there may be things I don't see or understand fully so I look forward to the discussion.

Leprechaun

I agree with Lep and DJ both.  I believe chasing can work given a mathematical advantage and proper money management.  However, if you can find an advantage at a single level of play that is where you should focus and decrease risk.

I think generally when discussing chasing people assume martingale money management.  I learned my lesson very quickly that this is can be "fatalistic" for even relatively short chases.  However, using a multi line labby system for money management effectively spreads out your betting burden between different level of plays.  You may be making a similar wager on game 1 of a chase as game 3.  You can always split numbers to keep the plays in your comfort level.  As long as you are winning a decent percentage your lines will cross off, losses will be recovered, profit made, etc.  Just like in flat betting or your unit sizes can be adjusted up or down depending on your comfort level (by splitting lines).

John.  Thanks for the reply.  This 7 game chase that Ace-Ace is on is neither impressive nor a testament to why chasing works as a theory.  It does just the opposite...it makes people believe that this strategy will work.  It baffles me that that thread has been so popular over the years and people point to it as a reason chasing works.  He is a VERY good capper...there is no doubt about that, but there is no mathematical basis to his chase besides the fact that he thinks (rightfully so) that he's very good.  Eventually, he'll lose 7 in a row.  It might take a long time, it might take a short time.  There is no way of knowing when it will happen, but that type of chasing is exactly what you shouldn't do.  If I throw darts at a board, statistically I have a 99% chance of not losing 7 in a row (note...not an exact calculation)...but it WILL happen if you have no edge.  The only way he would never lose would be if he had the ability to pick 100% of games correctly, which is obviously impossible.  Please reread my post if you don't understand this because it's important.  If your probability of winning is less than your break even %....you WILL lose eventually.  The length of how long it takes to happen can fool you into to thinking you have an edge.  If you did one bet a day, it might take 3 years before you lose...but if that one loss erases 3 years of work...how good was your system?  I could have the exact same success after 2 days and save quite a bit of time and energy.

Leprechaun