3.6 SD over on Verite?

Dopple

Well-Known Member
#1
Several people helped me understanding SD before although I still dont know what significance it has to "overcome" one SD of variance.

To the point: I have logged 642 rounds on Verite to rise from 1000 to 3965 playing 17125 in initial bets @average 27 per hand. At 1.5% I should have $256 so if we take ^642=25.33 * 27 * 1.1 = $752.53

Does that mean I am 3.6 SD over my EV if EV is roughly 1.5%?

I was on 6D playing all neg to TC1 $5, TC2 $50, TC3 $100, TC4 2 x $100.
 

Southpaw

Well-Known Member
#2
You are NOT going to be 3.6 S.d.'s over EV. It is almost statistically impossible to be that far above EV.

What you need to do is use a simulator to find the following two things:

(1) Your W.R. per 100 rounds and
(2) Your S.d. per 100 rounds

For convenience, let us assume that your W.R. per 100 rounds is $100. Further, let our S.d. per 100 rounds be $2500. Lastly, let us assume that after 1,600 rounds we have only earned $600. However, our EV for this many rounds was only $1600. Therefore, we are $1000 under EV.

One thing that a lot of people won't realize is that S.d. increases in proportion to the square root of the number of rounds played. So, we do the following calculation to find the value of one standard deviation after 1,600 rounds:

S.d. (after 1600 rounds) = ((16)^.5) x $2,500 = 4 x $2,500 = $10,000.

(You may find it odd that I used 16 instead of 1600, but we have to remember that there are 16 100 round segments in 1600 rounds).

So, now we need to calculate how many S.d.'s we are over EV:

# of S.d.'s over EV = $1000 (under EV) / $10,000 = .10 S.d.'s under EV.

Now, if we reference the following chart, you can find that the probability of being under EV by $1000 or more after this many rounds is 46.02% ((1-.5398) x 100%):

http://www.sjsu.edu/faculty/gerstman/EpiInfo/z-table.htm

SP
 

Dopple

Well-Known Member
#4
That might be clear I will look at it later when I have more time. My first problem (had trouble spelling arguement) is that if I am figuring SD right then my EV must be higher like over 2% which only means one thing.

I AM GOING TO BE RICH!
 

Dopple

Well-Known Member
#5
Here is what I was going off, I thought SD was the same everywhere for everyone.

Volatility in blackjack

Blackjack, like all gambling games, is subject to the ups and downs of Dame Fortune; fortunately, there is a simple statistical formula we can use to measure it, using "standard deviation".

Standard deviation in blackjack is calculated as follows:

• Take your total initial hands played
• Find the square root
• Multiply the square root by 1.15.

Here’s an example, using 200 initial hands:


(sq.rt.200 = 14.14) × 1.15 = 16.26
 

Southpaw

Well-Known Member
#6
Dopple said:
Here is what I was going off, I thought SD was the same everywhere for everyone.

Volatility in blackjack

Blackjack, like all gambling games, is subject to the ups and downs of Dame Fortune; fortunately, there is a simple statistical formula we can use to measure it, using "standard deviation".

Standard deviation in blackjack is calculated as follows:

• Take your total initial hands played
• Find the square root
• Multiply the square root by 1.15.

Here’s an example, using 200 initial hands:


(sq.rt.200 = 14.14) × 1.15 = 16.26
To get the precise answer, there is no simple formula for evaluating the S.d. It will be different depending on a whole slew of variables. And to be frank, I think the whole 1.1 figure is overly conservative from the sims I have run in the past.

SP
 

MangoJ

Well-Known Member
#7
Dopple said:
Here is what I was going off, I thought SD was the same everywhere for everyone.
And why is this different from someone else ?
SD is a statistical property just as EV, and will depend on the rules of the game. In fact it can even be calculated almost the same way as exact EV.
The figure you gave (1.15) is only a rough estimate (like claiming a house edge of 0.50).

For adding up EVs, proceed as:
total EV = betsize1 * EV1 + betsize2 * EV2 + ....

for total SD, proceed as
total SD = sqrt( betsize1 * SD1^2 + betsize2 * SD2^2 + ... )

where sqrt() is the square root, and SD1, SD2 are the SDs of your first and second hands (they change with the count). SD^2 is, taking the SD to the power of two.


Your example is a very specific case, where you flat-bet and play on a CSM (or ignoring count instead):
SD1, SD2, ..., SD200 = 1.15
betsize1, ..., betsize200 = 1.

Hence SD = sqrt( 1 * 1.15^2 * 200) = sqrt(200) * 1.15
 
#8
Not Even a First Step on a Thousand Mile Journey

You have only played 642 hands? That is such a small amount as to be about meaningless statistically.

:joker::whip:
good cards
 

Dopple

Well-Known Member
#9
So I just happened to stumble upon an extremely good time in my very first fraction of a step in this long journey.

This would have been one very good day at the tables and about one day is what I figure it would have been.

Thanks for the feedback, I need to get CVCX is suppose.
 
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