Robert: ? for Don, BJA3 Chapter 10

[Robert]

Don,

I have both BJA1&2. My BJA3 paperback arrived in Cincinnati, OH Thursday....Bettie is to be congratulated for that service, and the book is even more than promised. It displaces BJA2 as the finest BJ book of the 20+ that I own.

I need some help with my understanding of the new charts in Chapter 10, for the 4.5/6.0 S17, DAS game (unfortunately) that I Back-Count out here in the Midwest. It's also possible I never understood the old charts, but I must be making some mistake(s) with regard to the following:

From BJA2, with a $4,000 Bank, Play-All Optm Bet 400 Bank, $10-$80 nets $7.70 per 100 hands. With the same $4K Bank, Back-Counting Optm Bet 400 Bank, $10-$80 nets $14.10 per 100 observed hands.

From BJA3, $10K Bank, Play-All Practical $10-$80 nets $14.47 per 100 hands. For the same $10K Bank, Back-Counting Practical, 1-3 spread, $100-$150-$200-$300 nets $39.61 per 100 observed hands.

Dividing all of the latter Back-Count figures by 4, I get to the similar betting range of $25-$37.50-$50-$75 which nets $9.90 for a $2.5K Bank.

I assumed that all of the above sims incorporate Kelly Betting, and have nearly equivalent 13.5% ROR.

Q1: Why is the Play-All win rate nearly doubled ($7.70 vs. $14.47) when comparing BJA2 to BJA3?

Q2: In BJA3, how does Play-All $10-$80 net $14.47 when Back-Count $25-$75 only nets $9.90? Regardless of the $10K vs. $2.5K Banks and corresponding non-comparable RORs, the win rate differences don't make sense to me.

Thank you sir.

[Don Schlesinger]

> I have both BJA1&2. My BJA3 paperback
> arrived in Cincinnati, OH Thursday....Bettie
> is to be congratulated for that service, and
> the book is even more than promised. It
> displaces BJA2 as the finest BJ book of the
> 20+ that I own.

Thank you. Glad you're enjoying.

> From BJA2, with a $4,000 Bank, Play-All Optm
> Bet 400 Bank, $10-$80 nets $7.70 per 100
> hands. With the same $4K Bank, Back-Counting
> Optm Bet 400 Bank, $10-$80 nets $14.10 per
> 100 observed hands.

> From BJA3, $10K Bank, Play-All Practical
> $10-$80 nets $14.47 per 100 hands. For the
> same $10K Bank, Back-Counting Practical, 1-3
> spread, $100-$150-$200-$300 nets $39.61 per
> 100 observed hands.

Not quite. For the practical results that you quote, you need to use the "W/100 ($)" values, under "Results," and not the SCOREs, which are for optimal betting.

> Dividing all of the latter Back-Count
> figures by 4, I get to the similar betting
> range of $25-$37.50-$50-$75 which nets $9.90
> for a $2.5K Bank.

Again, you need to take 1/4 of $40.39, which would be $10.10.

> I assumed that all of the above sims
> incorporate Kelly Betting, and have nearly
> equivalent 13.5% ROR.

Not the BJA2 ones. They were never Kelly optimal. The BJA3 ones are (at least the "optimal"ones are!).

> Q1: Why is the Play-All win rate nearly
> doubled ($7.70 vs. $14.47) when comparing
> BJA2 to BJA3?

Er, $4,000 bank compared to $10,000 bank? :-)

> Q2: In BJA3, how does Play-All $10-$80 net
> $14.47

Practical nets $12.91.

> when Back-Count $25-$75 only nets
> $9.90?

$10.10.

> Regardless of the $10K vs. $2.5K
> Banks and corresponding non-comparable RORs,

10.60% vs. 14%.

> the win rate differences don't make sense to
> me.

Why is that? What doesn't make sense?

Don

[Robert]

> Thank you. Glad you're enjoying.

> Not quite. For the practical results that
> you quote, you need to use the "W/100
> ($)" values, under "Results,"
> and not the SCOREs, which are for optimal
> betting.

> Again, you need to take 1/4 of $40.39, which
> would be $10.10.

> Not the BJA2 ones. They were never Kelly
> optimal. The BJA3 ones are (at least the
> "optimal"ones are!).

> Er, $4,000 bank compared to $10,000 bank?
> :-)

> Practical nets $12.91.

> $10.10.

> 10.60% vs. 14%.

> Why is that? What doesn't make sense?

> Don

Even with an infinite bankroll, it doesn't make sense to me that $10-$80 Play-All, with the player at a disadvantage 73% of the time, would net more than a $25-$75 Back Counter always playing with an advantage.....I can't believe a zero vs. 14% ROR makes that big of a difference here.

[Don Schlesinger]

> Even with an infinite bankroll, it doesn't
> make sense to me that $10-$80 Play-All, with
> the player at a disadvantage 73% of the
> time, would net more than a $25-$75 Back
> Counter always playing with an
> advantage.....I can't believe a zero vs. 14%
> ROR makes that big of a difference here.

It is what it is. Note that the $75 bet doesn't get made until true counts of +7 or higher, and that these don't occur even 1% of the time. Meanwhile, while the back-counter is making $50 bets, the player of all is making $80 bets, which far offsets his betting of $10 while the back-counter bets zero.

Try not to find mistakes in the charts; rather, try to study them to see what's going on. It can be fun and instructive sometimes.

Don

[Robert]

> It is what it is. Note that the $75 bet
> doesn't get made until true counts of +7 or
> higher, and that these don't occur even 1%
> of the time. Meanwhile, while the
> back-counter is making $50 bets, the player
> of all is making $80 bets, which far offsets
> his betting of $10 while the back-counter
> bets zero.

> Try not to find mistakes in the charts;
> rather, try to study them to see what's
> going on. It can be fun and instructive
> sometimes.

> Don

Thanks for the explanation Don, that makes perfect sense...now. By the way, I wasn't really looking for a mistake, this is the exact game I play around here and I just wanted to make sure I understood the charts. I wasn't sure my assumptions in the question even made sense, so I'm glad you didn't have to correct that part.

[Bettie]

Thank you very much. I received many e-mails on Thursday and even more on Friday letting me know that the books were arriving around the country, and thanking me for getting the books out as promised. I haven't had the time to respond to everyone, so just let me thank everyone for the kind words and I am happy you are enjoying the latest RGE product.

Bettie

> I have both BJA1&2. My BJA3 paperback
> arrived in Cincinnati, OH Thursday....Bettie
> is to be congratulated for that service, and
> the book is even more than promised.