Sonny: Bad players DO hurt good players!

[Sonny]

I was playing around with a few card-eating strategies last weekend when I ran across something disturbing. My plan was to simulate a few situations where a teammate was purposely eating cards in negative situations. Whenever the count was negative, the teammate (betting table min) would always hit to hard 17 (against any upcard) and never hard-double. Splitting and soft-doubling were played according to basic strategy. Whenever the count was positive, the teammate would play accurate BS. The game was SD H17 nDAS with RO6 Pen.

I first ran a sim with the teammate and I both playing normally in order to get a "baseline" reading for win rates. I then ran a sim with the card-eater sitting to my right, eating cards before I played my hands. Under these conditions my win rate actually dropped by 0.4%!

Then I ran a sim with the card-eater sitting to my left, eating cards before the dealer played out his hand and before I placed my bet for the next round. This situation gave me the same 0.4% reduction!

I'm glad I simulated these conditions before I went out and started playing! I had just assumed, after reading all the literature, that this type of card-eating would increase my win rate, if only slightly. However, it just goes to show that bad players CAN potentially hurt good ones!

-Sonny-

P.S.-DON'T SIT NEXT TO ME!!!!!!

[Norm Wattenberger]

BJStats

[paranoid android]

Let me give this a try. Smart people please correct my inaccuracies.

Other players eating cards will tend to leave the true count the same on average. If you're being dealt a fixed number of rounds as you are with strict RO6, you're friend's card eating will result in deeper penetration during negative counts, and shallower penetration during positive counts.

If you are being dealt a fixed number of rounds, I believe you should want cards to be eaten *all* the time, whether in positive or negative counts, because you will see deeper penetration, but the same number of positive and negative hands. If on the other hand you are being dealt to a set penetration level, then card eating in only negative counts should be beneficial as it will reduce the number of hands you have to play in negative counts because the cut card comes out sooner. This will be offset somewhat by the cut card effect however though (to what degree I don't know).

Now, that doesn't explain why your sim shows a .4% disadvantage when only card eating during negative counts vs. the friend playing "normal" all the time. Anyone else know why? Could there be an error in the sim?

[Don Schlesinger]

> Now, that doesn't explain why your sim shows
> a .4% disadvantage when only card eating
> during negative counts vs. the friend
> playing "normal" all the time.
> Anyone else know why? Could there be an
> error in the sim?

I'm probably answering too quickly, but there is a difference between the (negative) edge that you have and the number of hands that you receive with that edge. You can lose less by playing fewer negative hands in bad situations, but your advantage during the play of those hands can be worse, due to deeper penetration.

I don't think all counts' edges are improved with deeper pen; that wouldn't make sense, as the basic strategist would have a greater edge just waiting for the deeper portions of the deck. Some counts -- the extreme negative ones, especially -- might be worth less rather than more, although I'm not 100% sure of this. The frequencies change also, and the whole thnig becomes a bit tricky.

Don

[Sonny]

I know you're going to tell me it wasn't enough, but I ran 60 million hands for each sim.

This leads me to another question: Is there a fixed level of standard error for a given number of rounds? For example, if I run 2 billion rounds I would expect a pretty accurate answer, but if I only run 120 million how much less accurate will my results be? It seems as though there could be a compromise between "number of rounds" vs. "accuracy" for us recreational players. Do I really need my win rate to be accurate to more than two decimal places?

Of course, I realize that that is exactly the point of a simulation. If I wanted a ballpark estimate I could use straight formulas to calculate the results much faster, whereas a simulation will (eventually) give you precisely accurate results. Still, there must be a compromise.

-Sonny-

[Norm Wattenberger]

> I know you're going to tell me it wasn't
> enough, but I ran 60 million hands for each
> sim.

Afraid so. Comparing two fairly close strategies requires a few hundred million rounds. One index difference requires several billion. But, your guy is playing the identical strategy. And, with a fixed number of rounds. Card-eating is normally examined with a cut card. You would need about ten billion rounds for a good answer. And, I suspect that their will be a tiny gain in win rate - not a loss. How much depends on the strategy. AOII would show a better improvement than HiLo.

Serious Blackjack Software

[Cacarulo]

That is a misconception. Bad players can hurt or not depending on which cards they are "leaving" or "eating" for us. But this that not apply with a fixed number of rounds as Norm have said. You'll need a cut-card in order to see this effect.

For example: Say the count is positive and the player sitting next to me "stands" on 11 vs 6. As you can see this is obviously a very bad player which I would love to have at my table! He is leaving the good cards for me.

Another example: Say now the count is negative and the same bad player splits 2's against a dealer ten. Now this guy deserves a kiss He is eating the bad cards for me!

See what I mean? Ploppies hurt when they eat our good cards and hence reduce the number of rounds played. They also hurt when they don't eat our bad cards.
If you're not convinced then you can try the following:

Scenario #1

player 1: "Never bust" strategy
player 2: "Counter" strategy

Scenario #2

player 1: "Mimic the dealer" strategy
player 2: "Counter" strategy

Which scenario would be better for the counter?

Sincerely,
Cacarulo

[DD']

when they yell at me for taking the bust card it hurts my feelings