Index justification

Hey all,

I've been working on memorizing more index plays. I find it easier to remember the numbers when I can think through the numbers logically. But 2 index numbers are giving me some trouble.

In Wong's book for a H17 multideck game, he says 9,9 vs A, split at +1.
For 10vA, double at +3.

I was just wondering why you need such a higher count to double a 10. I would think a 20 would be worth more than 2 19s for the same amount of money. It's not that I don't trust Wong, logic just helps me memorize the tables. Thanks for your help guys

RedChipper

Those don't sound right. What counting system is this for? 10 v. 10 is also weird, because of risk-aversion.

10v10 is a very risky play. While the EV comes ahead at a semi low count (it might be higher than +3 in a S17 game?), the doubled variance makes many people only play it at a substantially higher count.

As for 9,9, just remember that 18 is, on average, still a losing hand. Two 19s would be better. Especially against an A where you know the dealer doesn't have a blackjack.

I think the splitting of 9,9 vs A is more of a defensive move as opposed to the doubling of 10 vs A which would be offensive at +3.

With the double on 10 vs A you are only receiving one card so you would want a higher count to justify that move.

With the splitting of 9,9 you are able to split and draw more that one card per split hand.

When you double down, you lose the option of taking another card if you get a bad hand. When you split, you still have the opportunity to hit, split again, and/or double down until you get a good hand. If you plan on doubling your ten you will want a better chance of getting a good hand with only one card.

-Sonny-