David Spence: Streak sidebet

[David Spence]

Thank you very much to Norm and Don for their timely, outstanding answers to my previous questions. So, given the excellent answers I've received here so far, I thought I'd ask another question (give someone an inch and they take a mile...)

Anyway, on to the matter at hand. Some months ago, I did some analysis of the Streak sidebet. Here are the details of this bet:

Player may wager that he'll win 2, 3, 4, or 5 hands in a row. Pushes neither extend nor terminate the streak. Double-downs are treated as single wins or losses for the streak. Naturals, though paid 3:2, are treated as single wins for the streak. For streak purposes only, split hands are decided by majority. That is, win one, lose one = push; win two = add 1 to streak; lose two = end streak. Player may make multiple streak bets simultaneously. Payoffs are as follows:

2 in a row: 3:1
3 in a row: 8:1
4 in a row: 18:1
5 in a row: 38:1

For 3 in a row at 8:1, you need a win rate of (1/9)^(1/3) = .481 to be profitable.

For 4 in a row at 18:1, you need a win rate of (1/19)^(1/4) = .479

For 5 in a row at 38:1, you need a win rate of (1/39)^(1/5) = .481

(the 2 in a row bet at 3:1 is almost always a waste of time and money, since it require a TC of +14 to be profitable).

Derived from the stats at www.bjstats.com, here are the high-low decision numbers for the streak bet:

3 in a row: +6 or greater
4 in a row: +5 or greater
5 in a row: +6 or greater

If you reach the end of the shoe before your streak is decided, your streak continues with the first hand of the next shoe. Since this restarts the TC at 0, make sure there are enough cards left in the shoe before making any streak bet.

Now, at long last, the question: what deviations from basic strategy are appropriate when you have a streak bet placed?

For example, doubling down when you're on the 5th hand of a 5-in-a-row streak bet would probably be a mistake, as would many offensive splits.

By the way, thanks to Green Baize Vampire at bj21 for enlightening me on some of the subtler issues of variance on this bet.

[David Spence]

*in case someone is actually trying to answer my question, it would be helpful to know the relative size of the streak wager. Assume that the streak wager is 1/5 of the regular bet.

> Thank you very much to Norm and Don for their timely,
> outstanding answers to my previous questions. So,
> given the excellent answers I've received here so far,
> I thought I'd ask another question (give someone an
> inch and they take a mile...)

> Anyway, on to the matter at hand. Some months ago, I
> did some analysis of the Streak sidebet. Here are the
> details of this bet:

> Player may wager that he'll win 2, 3, 4, or 5 hands in
> a row. Pushes neither extend nor terminate the streak.
> Double-downs are treated as single wins or losses for
> the streak. Naturals, though paid 3:2, are treated as
> single wins for the streak. For streak purposes only,
> split hands are decided by majority. That is, win one,
> lose one = push; win two = add 1 to streak; lose two =
> end streak. Player may make multiple streak bets
> simultaneously. Payoffs are as follows:

> 2 in a row: 3:1
> 3 in a row: 8:1
> 4 in a row: 18:1
> 5 in a row: 38:1

> For 3 in a row at 8:1, you need a win rate of
> (1/9)^(1/3) = .481 to be profitable.

> For 4 in a row at 18:1, you need a win rate of
> (1/19)^(1/4) = .479

> For 5 in a row at 38:1, you need a win rate of
> (1/39)^(1/5) = .481

> (the 2 in a row bet at 3:1 is almost always a waste of
> time and money, since it require a TC of +14 to be
> profitable).

> Derived from the stats at www.bjstats.com, here are
> the high-low decision numbers for the streak bet:

> 3 in a row: +6 or greater
> 4 in a row: +5 or greater
> 5 in a row: +6 or greater

> If you reach the end of the shoe before your streak is
> decided, your streak continues with the first hand of
> the next shoe. Since this restarts the TC at 0, make
> sure there are enough cards left in the shoe before
> making any streak bet.

> Now, at long last, the question: what deviations from
> basic strategy are appropriate when you have a streak
> bet placed?

> For example, doubling down when you're on the 5th hand
> of a 5-in-a-row streak bet would probably be a
> mistake, as would many offensive splits.

> By the way, thanks to Green Baize Vampire at bj21 for
> enlightening me on some of the subtler issues of
> variance on this bet.

[Don Schlesinger]

> For example, doubling down when you're on the 5th hand
> of a 5-in-a-row streak bet would probably be a
> mistake, as would many offensive splits.

Depends on the double, of course. On some doubles, all you're going to ever take is one card anyway. :-)

As for the splits, there you're probably right. If the hand is an outright winner, to begin with, better to try to book the win immediately than to split and risk pushing, and having to "gamble" on the next hand.

Don

[David Spence]

Again, thank you very much for your quick, accurate answers.

Granted, the Streak bet is largely a waste of time, but in the casinos closest to my home, the limits are so low that I look for any excuse to get more money on the table :-)

By the way, I can't give enough praise for your writing style in Blackjack Attack. I think you may be the most eloquent blackjack author, as well as the most grammatically knowledgeable. Particularly dear to my heart was the correct use of "enamored of," as opposed to "enamored with." My girlfriend uses the latter, but, since it's almost always said affectionately, I never have the heart to correct her. But I digress...

> Depends on the double, of course. On some doubles, all
> you're going to ever take is one card anyway. :-)

> As for the splits, there you're probably right. If the
> hand is an outright winner, to begin with, better to
> try to book the win immediately than to split and risk
> pushing, and having to "gamble" on the next
> hand.

> Don