Blackjack-changes in house edge and strategy when playing multiple hands

This question could be answered (by someone so inclined) with a quick, short answer or with a long, complex one.
Since I'm incapable of answering it on my own, I'll take any answer that I can get :)

If I'm at 3rd base on a 6 or 8 deck blackjack game, just how much advantage can I gain (regarding changes to basic strategy) based on how many cards I've been able to view from the other players?

How much does the answer change if it's a 1 or 2 deck game?

Thanks in advance.

I can't give numbers, but an advantage definitely exists. I've been told, however, that it's negligible on a 6/8deck game.

However, regarding a single deck game, one source I'm looking at indicates a 1% edge on flat betting, given a number of other favorable circumstances.

Try running a search on 'depth charging'.

I agree with Venthus. It's not worth your time at 6-8 decks, and it's the reason why single-deck games are dealt face down.

In my experience, most places don't care too much if you show other people your cards. I also came across a site earlier today that gave tips for counting in pitch games too. You can oftentimes get an idea what a card is based on the cards that are known and how people react too. My problem is being able to *remember* what the count is while processing all this. Count the knowns, estimate the unknowns, work through my hand? Not a problem. But as soon as the next hand is dealt... can't remember a thing.

Quote: Venthus

However, regarding a single deck game, one source I'm looking at indicates a 1% edge on flat betting, given a number of other favorable circumstances.

1% is quite a bit overestimating. Based on my own research, the gain of knowing a single card increases playing efficiency by 0.02%. (The gain per card gets larger with each known card. I.e. 5 known cards are something like 0.12%).

"If I set up a seven-player table, with two rounds between shuffles, and I allow the third-base player, who is using the Zen Count, to see all of the cards of the players who play their hands before him, with a flat bet he will win at the rate of 0.77%. (This is with Reno rules, which allow doubling on 10 and 11 only, and the dealer hits soft 17; with downtown Las Vegas rules, where you can double on any two cards, but the dealer still hits soft 17, the flat-betting third base player will win at the rate of 1.06%, assuming he can see all of the other players' cards.)"
http://casinogamingstalk.com/4

Looking at it more closely, I guess saying the situation is 'favorable' is an understatement. One of the places I went to reshuffles after every round if there's even only 4 people, forget about 2 rounds of 7, and being face-up.

Sorry I thought you meant 1% per card. Your data states 2 rounds of 7 players (like 35 cards) gives 0.7-1.0%, which comes pretty close to 0.02-0.03% per card.

I appreciate the responses. Am I correct in assuming that I won't see a noticeable difference in the short-term if I visit a casino on occasion, but that the economy of scale (and speed) online might make it worthwhile to search out opportunities like this?


thanks,

Quote: MangoJ

Sorry I thought you meant 1% per card. Your data states 2 rounds of 7 players (like 35 cards) gives 0.7-1.0%, which comes pretty close to 0.02-0.03% per card.

Oh, no problem. I didn't run the math myself and if it was horrendously off, I'd like to know that too! Figured it'd be better if I just threw up the actual source, anyhow.

1% per card would be absolutely lovely too. 85% chance! =P

Quote: Scooter77

I appreciate the responses. Am I correct in assuming that I won't see a noticeable difference in the short-term if I visit a casino on occasion, but that the economy of scale (and speed) online might make it worthwhile to search out opportunities like this?

Most online casinos are CSM-style, in the sense that the deck(s) are shuffled after every hand, and most also don't allow for multi-handing. I've also heard that online casinos that have countable play have countermeasures against it, such as play analysis and whatnot... and won't hesitate to ban your account (and seize funds) as a result.

Ignoring counting and for CSM dealt hands, personally I find the differences help with marginal decisions. The most obvious ones that crop up are 12 versus a 4 and 13 versus a 2 (16 vs 10 also applies, but playing last base I try to keep the harmony going so nearly always hit my 16s) and I hit if I can see quite a few 10s have already gone.