In some basic strategy charts I've seen: stand on 7's against 10 (SD with DAS); also split 6's against 7, and 7's against 8 (DD with DAS). What's the rationale?
Be careful what you read. Just because someone took the time and money to print and/or publish something dosen't make it right.
Standing on a 7 against a 10. Why? You can't draw a card that could hurt you. That's a new one for me.
Also be aware of how old the chart is you are reading. Old is bad.
I would suggest getting a copy of Blackjack Attack v.3. It has BS charts you can take to the bank.
As to the rationale, generally, if the dealer is weak (showing 2 to 6), you'll want to stand, split and double more. If the house edge against you is greater (more decks in play), you'll want to split and double less. Somebody else will have to step up with an answer more sophisticated than that!
Get reliable charts and trust the math.
Standing on a 7 against a 10. Why? You can't draw a card that could hurt you. That's a new one for me.
I think the original poster meant a pair of 7's. Standing on 7, 7 vs. 10 is the correct BS play in single deck because of the effect of removal of the two 7's.
is you will have a higher expectation than perfroming any other basic strategy action. Splitting 7 7 vs 10 in single deck will yeild the overall (average) lowest $ loss (it's a losing play period). Splitting was determined to be superior by considering every possible occurrence that can play out, and an average $ win (or loss if in the negative) was determined (with probablities of each occurrence taken into consideration) much to the help of computers, since it's extremely laborous.
Yeah, that's the strange play in SD. But the reasoning stands. YOu can tell I play SD a lot.
The 7 is an extremely important card for deciding how to play 14v10. If you hit, 7 is the critical card to get. To hit against a 10, you need a reasonable chance of making 21, as the dealer often has 20.
A secondary effect is that when there is a high probability that the dealer 7 in the hole, hitting becomes a lot more attractive than standing.
In a single deck game when you hold 7,7, you have a 14 and half the 7s in the deck have been played. That is why hitting is a poor option, and standing is better.
The same effect would occur in a double deck game if you saw 4 7s (some of which might be in other players hands) and you held a 14v10.
Am wondering about charts that split 6's vs 7 and 7's vs 8 (DD with DAS)?
a defensive split which aren't always intuitive, except to say against the weaker dealer up cards (like in the case of 7-7 vs 8) when you can DAS, you will lose less in the long run by splitting because it is better to start with 7 on each of two hands than 14 on one hand....you could catch a 3 or 4 on your 7 which would put you in the drivers seat in a DAS game for that hand.
Same thing applies as to why you split 88 vs 9/10/Ace....except to a much greater degree.
Basic strategy is based upon which play will give you the best Expected Value. I always knew BS was supposed to be the "best play" but it didn't sink in until I discovered Appendix E in Stanford's Professional Blackjack (starts on page 298). Here you can see for yourself the rational (at least the numbers) behind BS.
For example the 7,7 vs. 8 that bigplayer explained:
Stand -.540
Hit -.408
Dbl -.858
Split (no DAS) -.423
Split DAS -.385
So if you have DAS then your best play is to split, if you don't then the best play is to hit. Seeing these charts made a huge difference in understanding the game for me!
HarperJoe,
I've got the numbers right here for 6,6 vs. 7 in SD:
Stand = -0.494,
Hit = -0.265,
DD = -0.599,
Split = -0.269 (NoDAS) & -0.201 (DAS).
Thus, with DAS you'd Split, without it you'd hit, and in either case, you'd pray ;-)
Or, if you're like the ploppies who usually infest my tables, you'd DD!
Dog Hand
