Forum: boardgames.stackexchange.com
Tags: <house-rules>
Title: 2 draw piles for convenience?
Question: Sometimes when the table is large enough, or people don't want to reach too far, a single draw pile is split into multiple draw piles.  This has always bothered me.  Does it bother anyone else?  Are there any statistical reasons to not split the draw pile?

Answers:
sents: text: Hypothetically, there's nothing wrong with splitting the draw pile.
text: Splitting a randomized deck into multiple decks, won't affect the randomization.
text: However, you need to carefully consider how you interact with the draw pile during the course of the game.
text: Do cards ever get put back on top of,into, or under the draw pile?
text: If so,having multiple draw piles wouldaffect the game.
text: For example, ifplayers can put a card on top of thedraw pile, can I choose to draw fromeither pile?
text: What happens when thedraw pile runs out?
text: If the normalrule is to shuffle the discard pileto create a new draw pile, youprobably need to wait until all drawpiles run out before doing so.
text: If you have multiple draw piles,will you also have multiplediscard piles?
text: If so, you need toconsider how you interact with thediscard pile, also.
answer_details: author: boardgames.stackexchange.com/users/159/Todd
score: 12
sents: text: Cards are randomized through shuffling not through picking the draw pile.
text: Statistically you should have the exactly same chances of drawing any particular card from either pile.
answer_details: author: boardgames.stackexchange.com/users/174/Kempeth
score: 10
sents: text: We do that with some games (including tiles in Carcassonne), but you have to allow people to pull from either pile they want, and don't reshuffle until both piles have been depleted.
answer_details: author: boardgames.stackexchange.com/users/96/Lance Roberts
score: 2
sents: text: When the table is inconveniently large and we are playing a game with a thick pack of cards, we sometimes spread the draw pile out into a large fan.
text: That way, everyone can reach conveniently and anyone who suspects they may be disadvantaged can draw from any part of the pack.
text: Myself, I can't see it makes any difference, but those who have some doubts can pick from anywhere and therefore have no grounds for suspicion.
answer_details: author: boardgames.stackexchange.com/users/624/Brian Hooper
score: 2
sents: text: While splitting the deck is statistically irrelevant, as others have said, it does affect those games in which you might have such options as "check the first X cards in the deck and put them as they were" (say, to simulate precognitions), "check the first X cards and reorder them as you wish" etc.
answer_details: author: boardgames.stackexchange.com/users/833/DaG
score: 2

Summary of the answers:
Splitting a randomized deck into multiple decks won't affect the randomization. You have to let people pick from whatever pile they want.
Hypothetically, there's nothing wrong with splitting the draw pile, as splitting a randomized deck into multiple decks, won't affect the randomization. If you split the deck you have to allow people to pull from either pile they want, and don't reshuffle until both piles have been depleted. While splitting the deck is statistically irrelevant, it  does  affect those games in which you might have such options as "check the first X cards in the deck and put them as they were" or  "check the first X cards and reorder them as you wish" etc.