Am I correct in the following?

The casino in my neighbourhood is offering a new sidebet for blackjack. When I asked the pitboss what the house percentage was for this bet he made some comments like "not much" and "in the real game it's always different". In other words, he wouldn't tell me.

The rules are the following: before any cards are dealt, you can wager 5 guilders on the hand of the dealer. If the dealer gets a blackjack in spades, you're paid 100 times that bet. If the dealer gets a blackjack in diamonds, hearts or clubs, you get paid ten times. When the dealer gets a blackjack in mixed suits, you get paid 5 times and when the dealer busts, nothing happens with the side bet. In all other cases, you lose the side bet.

My calculations are as follows:
-The chance of the dealer getting a suited blackjack in spades is about 0.003.
-The chance of the dealer getting a suited blackjack in another suit is about 0.009.
-The chance of the dealer getting a non-suited blackjack is about 0.036
-The chance of the dealer busting is about 0.28 (I'm not sure if this is correct, I used the busting percentages given a certain upcard from The Theory of Black Jack).
-The chance that you lose your sidebet is about 0.67.

All this gives you an expected value of -1,43 guilder on your 5 guilder bet. Which means the house has about a 28.5% advantage on this bet. No wonder the pitboss wouldn't tell me.

Please let me know if my calculations are correct and if not what they should be.

Thanks,

Peter Woerde

PS: It's a six deck game and unfortunately counting isn't possible (CSM's).

If I understand this properly, I get:

500 X .003 = 1,5 guilders

50 X .009 = 0,45 guilders

25 X .036 = 0,9 guilders

Total wins = 2,85 guilders

-5 x 0.67 = -3.35 guilders

Net result = -0,5 guilders

or -10%

If my results are correct, it's not as bad as what you calculated, but it's still a terrible bet.

Cheers,
sargon

I forgot to include the non-suited blackjack in my calculation.

Peter

Regardless of the exact figures, the bet has a large house advantage and falls into the category of "sucker bet," as do most blackjack sidebets.

Blackjack has one of the lowest house advantages of any game in the casino. Being greedy, casino owners are always looking for ways to increase this edge, hence the sidebets.

Rest assured that any BJ sidebets are not there to enhance the casino experience, provide more fun, etc. They have one purpose - to increase the overall house advantage on the table.

An Eastern Wa. card joint offers a $1 bet "option". If you get 4 all black, or 4 all red Aces, you win the pot (6 Dk game, You'd have to get 2 dealt, split aces, and get two more). Last time I was there, the Jackpot was $240,000+.

At what point (dollar amount) does the $1 bet makes sense to play, if ever??

... $400,000,-. My calculations give an amount of $391,190.92 to get an even break.