Video Poker and Random Number Generators (RNG)

A reader sent me a question this week:

If video poker machines have a RNG in them, how does knowing how to play the game come into play since the results are already determined because of the RNG?

Here was my reply:

In the case of video poker (in most jurisdictions), the RNG serves to merely emulate a live deck, not to pre-determine the outcome.  Many years ago, video poker machines supposedly dealt 10 cards upon hitting the "Deal" button.  5 were face up (that the Player could see) and 5 more face down underneath each of the up cards.  When the Player decided which cards to hold and hit Draw, the cards he discarded would be replaced with the ones that were 'underneath' these discarded ones.

For some reason, this did not sit well with some people (and there was some concern that if someone had the RNG code, he could figure out what the 5 hidden cards were).  Over the years, from what I understand, the code for video poker has changed so that the machine deals 5 cards when the Deal button is hit and then when the Draw button is hit, it will deal the appropriate number of cards from the deck, replacing the discarded ones.

In the end, the exact method of replacement doesn't really matter.  The fact that the machine knows what cards were dealt face down or if it knows what the next 5 cards will be does not change anything for the Player.  You don't know what the hidden cards are, so you have to use the probability of each possible outcome combined with the payout of that outcome to figure out what is the best play.

Imagine if you were sitting at your dining room table and you deal 5 cards face up and then 5 cards face down as the 'replacements'.  AS you deal them face down, you show them to a friend (but not to yourself).  The fact that your friend knows these values does NOT change how you should play your hand.  The fact that your friend can know every possible outcome does not change what you should do.  Obviously for the ONE SINGLE hand, this knowledge might cause HIM to play the hand differently, but as the Player you have to assume that those 5 down cards are random - equally likely to be any of the remaining 47 cards.

This is the only purpose a RNG serves in video poker.  It does NOT determine what the final hand will be or what the 5 dealt cards will be in totality.  It only decides which of the 52 cards will be the next one dealt - just as if you were holding a real deck.  If a casino wanted to, they could turn video poker into a table game (not sure how they would handle multiple players, but imagine a live deck and a single player).

By contrast, slot machines do NOT work this same way.  The machine does NOT determine what symbol will show up on each real independently.  Rather, the RNG determines which of the specific final outcomes will be shown to the Player.  This would be like the RNG determining that the Player will be dealt a Pair of 10's and assuming you discard the other 3 cards that NOTHING will improve your hand.

In video poker only the cards are dealt randomly using the RNG.  In slots, the outcome is determined by the RNG.