ICM Quantified - First Set of Results

[rvg72]

I believe that ICM is a great way to model $ev but I also did not believe that it was completely accurate compared to actual $ outcomes in some situations and I wanted to find these differences and see if there are practical applications for this.

So, I wrote software that analyzes ICM and real outcomes for every player in every hand of an SNG and stores the results in SQL database for processing. My first run through this incorporated results from about 1700 SNG's and my intention is to continue to increase the sample size. Any contributions are appreciated.

So far the results have been extremely interesting at least to me. In this first go around I have categorized stack sizes into 5 groupings:

Very Small = bottom 10% of samples
Small = 10th to 30th percentile
Average = 30th to 70th percentile
Large = 70th to 90th percentile
Very Large = top 10th percentile

So these grouping are done per level or per number of players remaining so obviously relate to different stack sizes for each level.

At EVERY level, a subtle but distinct thing happens between ICM $ and Real $. There is an S curve... I think this is pretty huge. At every level very low stacks are highly overvalued, low stacks are overvalues, average stacks are pretty close but vary by level, large stacks are highly undervalued and very large stacks are somewhat undervalued.

I then looked at it by number of players remaining (instead of by level) and found similar trends. For example, here are the results when there are 4 players remaining (note: all results here are based on 800 chip games. I do expect similar trends albeit with different nuances for 1000 chip games but have not looked at those results yet):


and here is the data:



Thses differences are not small... Obviously this will change the results of ICM $EV calculations used to determine optimal push / fold scenarios. Lower stacks will find that hands that were previously easy folds now become easy pushes and conversely larger stacks have even more value than ICM gives them credit for and therefor many of the marginal and not so marginal pushes need to becomes folds.

I plan on charting this for every blind level and # players remaining and then moving on to things like determining where you are in relation to the blind and blind size and how that affects real $ results.

Comments?

rvg

[citanul]

this [censored] rules.

keep it up.

c

[zabt]

Very cool. And, I suspect not a big surprise. I'm very interested in seeing the by position results.

[DonkBluffer]

[ QUOTE ]
this [censored] rules.

keep it up.

c

[/ QUOTE ]

I agree! I really feel like we (you) are achieving something here.

edit: maybe a stupid question, but could this be caused by calling ranges? A (very) short stack will often be called by at least one, and often two players if he goes all-in. A big stack on the other hand has more FE.

[rvg72]

[ QUOTE ]
Very cool. And, I suspect not a big surprise. I'm very interested in seeing the by position results.

[/ QUOTE ]

The "By Position" will be very interesting... I suspected that big stacks were undervalued when blinds were high and small stacks were overvalued when blinds were high which was true. What I completely did not expect was that this holds true even at Level 1... I had suspected the opposite trend when blinds were low but that was clearly not the case - in fact it seems that the difference is greater at earlier levels.

rvg

[jb9]

[ QUOTE ]
Lower stacks will find that hands that were previously easy folds now become easy pushes and conversely larger stacks have even more value than ICM gives them credit for and therefor many of the marginal and not so marginal pushes need to becomes folds.

[/ QUOTE ]

Very interesting. Thanks for putting the data together and for sharing.

[adanthar]

This is not at all surprising but I think everyone on the forum needs to see it. Thanks.

[J-Lo]

do u want more HH? i'm sure there are people here who will send u thousands of HH to help this analysis.

[ZeroPointMachine]

Very impressive.

I feel slightly vindicated for all the times I've argued against the world for pushing the small stack aginst ICM wisdom.

[sofere]

Fun little coincidence...sum up the % differences between ICM and actual and you get -10%. Where have I seen that number before? [img]/images/graemlins/blush.gif[/img]

Excellent work btw, interesting stuff. Something I think a lot of people believed was true but is now quantified. ICM doesn't really take into account the lack of fold equity of small stacks and the intimidation factor/increased steal ability of big stacks.