Standard Deviation/Expected Value

[thepheonix]

Hello... I have been tracking my wins and losses with a computer program. I understand the concept of Expected Value as it applies to Casino Games against the house, but does anyone know how it applies to hold'em. I also understand Standard Deviation, but I am unsure how to use the values that my computer program gives for my Standard Deviation. Are there any people out there willing to help??

[Dave B]

I guess I need more info. What data are you getting and what do you want to know???

I guess if you program tells you that you are making $15/hour w/ a standard deviation of $6/hour, then 50% of the time you will play within 1 standard deviation of $6 ($9-21 hour), 75% of the time you should be within 2 standard deviations ($3-27/hour) and 93% of the time you should be within 3 standard deviations ($-3-$33/hour)

I could be a little off on the 50%, 75% and 93% (college econ major was 10 years ago!)-but it is something very similar.

[FatJoe]

actually 50,75,93 are the right numbers but the rule youre thinking of only applies to things called "normal" distibutions. in other words unless his results form a perfect bell curve (which they don't) you can't really say that.

basically all your standard deviation can tell you is that
1. a high standard deviation in relation to the stakes of the game means you're playing looser.
2. a higher standard deviation in general means you play for higher stakes.

basically if you see your standard deviation going up, it probably means you're playing looser or not very consistently. if it's going down it probably means you're either playing tighter or more consistently.

[Dave B]

Why wouldnt constant play (not playing more tight or aggressive, but just playing your style) result in a normal bell curve? Most of the time you will preform at X, the greater the extreme, the less the likelihood of that occurance.

I am assuming that it isnt evaluating hand but hand, but by performance per hour.

[FatJoe]

the key word is "perfect." not very many things in real life actually come out that way. the curve of your poker results would be shaped like a bell, sure, but it wouldnt be a "normal" distribution in the textbook sense. for every hour/session that you win 1000 less than your average, do you have exactly one hour/session where you win 1000 more? of course not. and if youre a break even player and you have a rule where you quit after losing 1000, you will never have a -2000 session but that doesn't mean you'll never win 2000.

i just meant that the 50, 75, 93 rule only applies to very specific (and usually artificial) distributions.

[reidy125]

The normal distribution graph basically tells you what you can expect from your next session. It is very complicated, it wil take a while to explain, but here goes.

Imagine a curve that srats from the bottom left of a graph, a bit like this:

_-_
/ \
/ \
__-- --__
--------------------
now visualise that as a graph(!) anyway, basically the further yo go to the extremes, the less chance there is of theat happening, i wish i could import a file to show you, if you on average earn 2 BB's per hour, then that would be right in the middle, the peak of the graph. The standard deviation is 0, if you earn 2BBs per hour EVERY hour, exactly, standard deviation is the fact that this doesnt happen, it's impossible, but how much you vary from this is where you stand to the left or right of this, if you vary a lot, you will be to the far left or right, whreeas if you vary little you will be close to the middle. How close you are depends on what type of player you are, what game you are in etc etc your opponents, luck. Notice that at either end of the graph the line is lower, this is because there is less chance of it happening, in the middle is basically the hourly average, you have a good chance of htiing the middle about (68%) i think.
if 2 BB id the middle, then 1 standard deveiaiotn left could be 1 BB, 1 standard deviation right could be 3BB, this is the 68%, between 1 and 3 BBs, then 2 standard deviations would be 0 and 4 BBs, the chance of 2 BBs wither end is 2.5% either side of the average, so thats 5%. If there is a concept you dont understand just write back. I only know this cos i did a level maths, you dont have to know it to play poker, unless you are a real stst fan, but you wont improve as a result of this. A tight player can have a high standard deviation just as mush as a loose player, its the swings that happen, at low limit poker, 1 standard deviation either sire could be 0BB and 4BB (68%) of it being betweek this whereas 2 SD's will be -2BB and 6BB (95%) chance of it being between this

[reidy125]

the graph didnt work, cos the program auto formated it damn, anyway, its like the shape of eeeeerrrrrrrrrrrr
i dunno, a bell? like someone said?
i'd say a perfect kind of hill that gets steeper as you walk up it, get me?

[Replic]

Care to share the program?