My Kelly math

[Automatic Monkey]

I've decided to recalculate my spread using an approximation for Kelly proportional betting that I found online: Bet= Bankroll * (Advantage/Variance)

I used IBA% becuase that's just what I'm used to using- my first question is whether that or TBA% is more appropriate.

Here are my results for two games I play, I was surprised:

Game 1: 8D, 1.5 pen, S17, DOA, DAS, LSR, BU = $10, Wong out at -2

TC Advantage Variance Bet (rounded)
2 0.00155 1.308 $10
3 0.00411 1.304 $30
4 0.00635 1.301 $50
5 0.00987 1.297 $75
6 0.01139 1.298 $90
7 0.01525 1.298 $120
8 0.01729 1.305 $130

Game 2: 6D, 1.5 pen, S17, DOA, DAS, LSR, BU= $10, Wong out at -2

TC Advantage Variance Bet
2 0.00247 1.308 $20
3 0.00534 1.303 $40
4 0.00776 1.3 $60
5 0.01107 1.296 $80
6 0.0134 1.298 $100
7 0.01683 1.297 $130
8 0.01896 1.303 $150

What was so surprising is how much the bet changed, especially on the low end, just by changing from 8D to 6D. This would make the 6D a significantly better game, even more than just the small advantage caused by a smaller number of decks. So my second question: did I do this right?

 

[phantom007]

What was your First Question?....

As to your 2nd Question, I just don't know....I do not fully understand your #'s.

I feel that in general, and most of THE BOOKS agree, that SD is better than DD is better than 6D is better than 8D is better than Infinite-D is better than 6:5, etc. I suggest only, that CSM's may actually be better than Infinite-D.

That is presuming rules/pen. otherwise the same, and that you are a "Play-All" type of guy/gal.

One of the books in my BJ library, which is now extensive enough that I cannot find it right now, suggests that IF you make your Max. Bet at above TC = +5, then:

---In approx. #'s: 24/12/6% for SD/DD/6D. Thus, if #100 hands/hour, one gets about #24 Max. bet opportunities in SD, #12 in DD, etc.

---Therefore, depending on whether you are a Compulsive Extrapolator, or a Recreational Extrapolator, one can extrapolate that in 8D, you only get Max. Bet chances 2-4% of the time/hands.

Now for True Wongers, wherein about 1/2 of DD games and most all SD games prohibit mid-shoe entry, 6D is the game of choice. Certainly, in 8D, once one gets to strongly Pos. Ct.'s, they last much longer, but for most of us, we would be asleep by the time they came around.

Maybe this helps explain the #'s that you generated.

Wonder if 6:5 BJ allows Mid-shoe entry?

GRIN!

phantom007.

 

[Automatic Monkey]

First question is IBA% vs. TBA%...

... for calculating Kelly bets. Oh one thing I left out, these numbers are for a bankroll of $10K. What I've done is set up a spreadsheet. It includes a summation of all my assets available for blackjack, and another section with the advantages at different true counts for all the games I play. As my bankroll changes, I can just look down to the spot with the game I'm playing that night and it gives me my Kelly bets for that game as a function of TC.

6:5 mid-deck entry: yeah I started that fight awhile back. It's allowed. The numbers reveal that Wonging 6:5 SD is about as profitable as playing a lousy 8D game so Wonging the 6:5 isn't worth it unless you are really bored or desparate.