indice question

The indice q I have is why does it make sense to double 10 against a dealer 10 with a favorable count? It seems the dealer would have the same opportunity as the player to make the best hand.

I've never looked into why but my guess is that the increased probability that the dealer will bust a stiff overcomes the additional money wagered at and above the index number. If no one else responds, I will look at BJA and see if I can find the answer but I'm pretty sure someone will know off hand.

The answer to this isn't easy nor terribly intuitive. First, let me state that, from a risk-averse point of view, this is the quintessential play, which accounts for the bulk of all the edge that can be acquired from using a slew of R-A indices. (Note to laotse: one index, two indices. There's no such word as "indice.")

This is a play that we say is not very volatile as the count changes. By that, we mean that the expectations remain rather stable, with a rising count, such that the change in e.v., from one TC to another is very, very slight. At TC = 0, the player edge from hitting (as many times as he wants) is a very slight 0.03%, while the edge from doubling (one card only) is ever-so-slightly negative, at about -0.01%.

As the count rises, the edges for BOTH hitting and doubling each rise, but because we're betting twice as much, when we double, the double-down e.v. eventually catches the hitting e.v. at +4 and then passes it, as the TC goes even higher still (we need +7 to make the R-A play).

Consider, also, that the player has a greater chance to make 21 than the dealer, because the dealer has already checked that he doesn't have a natural, whereas the player has, roughly, one chance in 13 (7.7%) to catch an ace on the double. The dealer, on the other hand, turns his ten into 21, with multiple hits, less than half that percentage.

Finally, although it is true that IF the dealer turns out to be stiff, he will break more frequently with the higer count, unfortunately, he actually breaks, overall, LESS with a ten up at high counts, because, of course, his chances to be stiff in the first place decrease with the rising count.

All told, this is not a very advantageous play to make at any count, and if you never doubled 10 v. 10 for the rest of your life, you wouldn't be missing very much at all.

Don

Since the Ace is worth twice it's normal value in this play, the player that uses an ace/side system has a more accurate count to determine wheather hitting or doubling is the proper move. As the pen increases, the chances of mis-playing this play (hit or double) also increases for the non-ace/side system player.

This may seem trivial, but usualy, when doubling is called for, a bigger bet is already in the circle. There is no such thing as too much info when betting your money.

I would be leery about doubling this play on a close call without the knowledge that an ace/side count gives.

Frenchman

As I am sure you know, either indexes or indices is proper. All of my dictionaries, including a 1986 edition of the Oxford English Dictionary, list indexes before indices as an optional choice of the plural. OED breaks this down further, assigning indices as the preferred in three senses, none of which seem to fit exactly the sense utilized in card counting. I don't think anyone can be faulted for using either indexes or indices in any sense. As you point out, "indice" is not among the acceptable forms, except possibly as a uncommon typographical error. :-)

"As I am sure you know, either indexes or indices is proper."

Yes, of course. Just one Latin, one English.

"All of my dictionaries, including a 1986 edition of the Oxford English Dictionary, list indexes before indices as an optional choice of the plural. OED breaks this down further, assigning indices as the preferred in three senses, none of which seem to fit exactly the sense utilized in card counting. I don't think anyone can be faulted for using either indexes or indices in any sense."

When the word refers to anything numerical, such as stock indices (indexes), or the blackjack sense, you may surely use either. But, when you refer to the index of a book, for example, you wouldn't talk about "indices." You would always say "indexes."

"As you point out, "indice" is not among the acceptable forms, except possibly as a uncommon typographical error." :-)

People just look at the plural and back-form a singular that doesn't exist. It's a little like "kudos." You can't havee one "kudo"!! (But, in fact, you use a singular verb after "kudos.")

Don

We could go on forever, regarding language points, but I have to say that one of my favorites of all time is that "flammable" and "inflammable" mean exactly the same thing! :-)

(Actually, I think that the original word was "inflammable," meaning that something could burst INto FLAMES. But, when "inflammable" was put on labels, people erroneously thought that the product could NOT (prefix "in") catch on fire, and so, for safety reasons, they felt that "flammable" would be clearer.)

Don

Its common use is to describe something which is a base component shared by all members of a group as in "dumbing down to the least common denominator." However, in mathematics, a least common denominator is greater than or equal to any of the numbers involved. The more appropriate metaphor would be "greatest common factor," which is less than or equal to the numbers.

Example, the LCD of 10 and 15 is 30, but the GCF is 5.

Is the misuse of LCG an example of dumbing down to the GCF?