Insuring for Less:

[jack.jackson]

Is there ever a situation, where it would make mathmatical sesnse to insure for less?

For example, if you make $50 bet and take FULL insurance at +6, but the count happens to be +5, would it not make sense to at least insure for $10?

I mean that seems, like a pretty fine line between insuring for $25 or not insuring for anything at all.

 

[BMDD]

Just to understand your question better, are you asking if there is a point at which doubling for less is risk-averse?

 

[jack.jackson]

Just to understand your question better, are you asking if there is a point at which doubling for less is risk-averse?

Yes! In my example above, wouldnt it make sense, to be something between +1thru+5 if you take insurance at +6?

 

[BMDD]

Interesting.. I certainly wouldn't buy insurance at all below my index as I would be at a disadvantage.

Lets assume though, that I have a max bet out and the insurance desicion is right at my index, so perhaps my advantage is at .5% for insurance.. about the advantage I would have on a +2 TC on my main blackjack bet. If the bet I would normally make at +2 is less than half my max bet then why should I be putting up more than that amount now to insure my max bet?

..Were you thinking along the same lines, JJ?

I would imagine that the volatility of the insurance bet is substantially greater than the main BJ bet, making such risk-averse insurance bets impractical even if there is mathmatical evidence to support making such a bet.


naww, i think we're on to something here.. insurance bet spreads are the next big thing in BJ. haha.

 

[Renzey]

Is there ever a situation, where it would make mathmatical sesnse to insure for less?

For example, if you make $50 bet and take FULL insurance at +6, but the count happens to be +5, would it not make sense to at least insure for $10?

Let's think about that provocative question in this light:
If while sitting at the blackjack table, I offer to flip a coin with you and give you payoff odds of 6-to-7, I'd be taking the same advantage over you as the Insurance bet at a neutral count.
Now, if when your level two true count is +5, and at that moment, I increased my offer to 49-to-50 odds on the coin flip, you'd have the same 1.2% disadvantage on the flip as you would have on Insurance at that count.

A - Should you take the coin flip proposition for a modest amount?
B - Does the correlation between losing the hand while winning an Insurance bet have a significantly more mitigating effect on your bankroll than the coin flip deal?
C - With either bet, how will they affect your bankroll over time?

I know the answers to A and C, but I'm not sure about B.

 

[BMDD]

Renzey,

What about insuring for less when insurance yields a slight positive EV from a variance perspective, as described in my above post?

Now, could insurace decisions possibly(dare I say..) correlate to the quality of the hand?

 

[London Colin]

There's a section in The Theory of Blackjack that covers one possible scenario: 'Kelly Criterion Insurance'.

It considers the case where you are dealt a blackjack. When should you take insurance, and how much for?

I get the impression it may be only of academic interest, unless you have significantly overbet your bankroll in the first place (and are able to do some pretty complicated mental arithmetic at the table), but formulae are given:


Take insurance if p ,the proportion of tens remaining in the deck, is greater than 1/3(1+f), where f is the fraction of your bankroll which you have bet.


Insure x = 3p + (3p - 1) / f.

(Where x represents the fraction of your original bet to insure. E.g., if you had bet $100 and x was 0.5, you should buy $25 worth of insurance.)

 

[Deathclutch]

Here's an interesting thing on taking insurance on a hand you plan on surrendering. http://www.blackjackinfo.com/bb/showthread.php?p=167893

 

[jack.jackson]

Well I can't count the number of times, ive contemplated taking insurance, while "MY index" was right on the ragged edge. It seems irrelevant too me, if your playing 1 or 2 hands only, whether its a Maxbet, or even if you have a BJ on one or both of your hands.

What doesnt make sense "is that" if I were making a $50 bet, and my index was right around +4 or +5 how would NOT, making any kind of wager, not be in order, when I would bet $25(full ins) @+6?

It seems even if, I were to wager at least $5, it would have to be mathematically correct.

 

[SleightOfHand]

Well I can't count the number of times, ive contemplated taking insurance, while "MY index" was right on the ragged edge. It seems irrelevant too me, if your playing 1 or 2 hands only, whether its a Maxbet, or even if you have a BJ on one or both of your hands.

What doesnt make sense "is that" if I were making a $50 bet, and my index was right around +4 or +5 how would NOT, making any kind of wager, not be in order, when I would bet $25(full ins) @+6?

It seems even if, I were to wager at least $5, it would have to be mathematically correct.

No, it is not mathematically correct (EV-wise) to make any kind of wager when the index has not been reached. The index tells you when the wager becomes a +EV wager, so making bets prior to that point means you are losing money. The index does not consider fractions of a bet. If the index has not been reached, betting less means you are losing less money than if you had bet more. However, when the TC is very near the index (very near meaning fractions of a TC), there may be occasions where you may want to bet differently for the sake of variance (as there is in fact a relationship between the insurance bet and the main bet, hence the term insurance).

 

[Finn Dog]

One additional point to keep in mind is that insuring for less slows the game down (with the dealer having to think more--perhaps even double checking some math with the Boss).

FD

 

[BMDD]

One additional point to keep in mind is that insuring for less slows the game down (with the dealer having to think more--perhaps even double checking some math with the Boss).

FD

Perhaps, but if it's a single color and clearly less than half your bet they will just cut in to it twice.

 

[Renzey]

Insuring blackjack for less by ploppies

I've tried to convince decent civilian players who can't bring themselves to eschew even money that they should insure their blackjack for much less.

If they have a $30 blackjack against an Ace, I encourage them to insure it for $5. They will either win $10 or $40. They will never get stuck with a dreaded push, and it's a lot better play than settling for even money.

They usually shake their heads and say it makes no sense. I'll have to admit though, that trying to insure a blackjack for less usually stops a game cold -- as if the power went out. I'd done it many times to skirt around the even money issue, and finally decided it wasn't worth the glaring attention it got.