Paying out blackjack against a dealer blackjack half the time

I have mentioned this in passing in some random comment, but I have found a game that pays out blackjack even though the dealer has blackjack.

im almost sure its a bug in the game as i have made sure that both scenarios do the same thing.

the bug goes like this :

You have blackjack

The dealer has blackjack

normally you would push

in this game, IF the dealer gets a 10 first, asks you if you want insurance, then does the normal procedure, where in my jurisdiction is to check for blackjack. if the dealer ALSO has blackjack it pushes.

here is the bug

if the dealer is dealt an ace FIRST , and you also have blackjack, you actually win and recieve the normal 3:2 payout no matter what

can someone calculate the increase in MY edge increase based on these statements?

Exact answer depends on how many decks you're playing with. I assume it's not a 1-deck game, but in that case the situation you describe happens about 0.08% of the time and you gain +1.5 units in that instance, for a net +EV of 0.13%.

In a 6-deck game, the situation happens about 0.108% of the time, so your net +EV is +0.16%.

Do you know the theoretical RTP in this game?

Quote: stooge

Do you know the theoretical RTP in this game?

i do not know im assuming 8 decks though, or anything over 2 decks as i have recieved the same cards as the dealer plenty of times.

Of course, but getting the same cards will happen more often than both receiving blackjack. And, in particular, both getting blackjack with the dealer showing an Ace up is an even more specific situation.

At it stands, the chance of being dealt blackjack is less than 5%. If you want a very rough calculation for your question, then let's assume your BJ and the dealer's are independent and both have a 5% probability. In reality the probabilities are both less than 5%, and the dealer's probability of BJ after you have BJ is smaller as well.

So then you and dealer both have BJ 0.05 * 0.05 = 0.0025 of the time. Now, your glitch only happens in the case where the dealer's upcard is an Ace, which is exactly half of the times when the dealer has BJ in this case. So the situation you described happens 0.00125.

Now if you multiply by the increased EV of 1.5 units, you get an upper bound of 1.5 * 0.00125 = 0.001875.

That's the rough calculation. In reality, the increase is more like 0.16% as I showed up above.

If it's a video BJ machine, the best RTP I've come across is around 99.77% (Does anyone know any better ones out there?). In that case, the glitch would get you up to 99.93%. Assuming the comps are calculated precisely based on the 99.77% level, then it might be possible to eek out some +EV from the comps on this machine, but it seems razor thin based on this glitch alone.

I’ve never seen a game that asks if you want insurance when the dealer shows a 10

Quote: michael99000

I’ve never seen a game that asks if you want insurance when the dealer shows a 10

Same here. I was going to mention that, but assumed it was a typo in OP.

Quote: stooge

Same here. I was going to mention that, but assumed it was a typo in OP.

Nice odds for the house.

Paying you 2-1 on something that happens 1 in 13 times

I wonder why they don't offer that? Too egregious, even for a casino?

Quote: michael99000

I’ve never seen a game that asks if you want insurance when the dealer shows a 10

you are correct. it is a typo.

sorry everyone let me correct this

if the dealer has a 10 showing
the dealer does not check for blackjack til the end of the game.
people can double down etc and still lose to blackjack.
and you end up pushing if you have blackjack at the end of the round

if the dealer has an ace showing,
the program offers insurance, then checks for blackjack

i find in the second scenario is where the program has a flaw, and if you also have blackjack it will pay you 3:2 like normal