Just curious if there is a standard practice for choosing random cards from hand at competing REL.

Example:
Adam casts Hymn to Tourach targeting Naomi

Generally any practice that both players agree upon is considered
acceptable (dice, layout and pick, etc.)

Just like determining who chooses play/draw, it's whatever the players can agree on as long as the person choosing the random object doesn't know its identity before the selection is made.

Ok just curious what is most common… Naomi randomizes and Adam chooses two?

As long as adam hasn't the foggiest idea which is which, then yeah that
would be acceptable.

In my experience rolling dice is most common at competitive.

Laying out the cards and rolling an appropriate die is the most common in my experience. Players will normally indicate which way they intend to count (1 = left, 6 = right, for example). It's cleaner than picking two, for me, but players will use whatever they have to hand.

~ Jack
L2, London

In general, picking 2 is frowned upon due to known psychological biases towards/against certain positions in a fanned-out hand. This can lead to cheating which is extremely hard to detect. Rolling dice is the most popular method I've seen.

Originally posted by Lyle Waldman:

In general, picking 2 is frowned upon due to known psychological biases towards/against certain positions in a fanned-out hand.

You can always shuffle the cards before the opponent chooses. That's what I do most of the time since it's a bit quicker than getting a die and assigning numbers, then rerolling the three 6s you'll inevitably roll for the 5 card hand.

That's another angle as well… I've seen players roll a D6 for randomly choosing a card out of a 4-card hand, which is fine if you re-roll on the 5 or 6.

But they assigned the cards numbers 1->4 left to right, and wrapped around with cards 1+2 getting 5 and 6, so they didn't have to re-roll. Not quite realizing they're over-representing cards #1 and 2. Probability just doesn't click for some folks =)

This is the reason why I don't like rolling a die in this situation. If people know what they are doing, it's fine, but some (many?) don't.

Randomisation conversations have come up repeatedly on these forums. Two threads that cover the subject in some depth:

http://apps.magicjudges.org/forum/topic/4595/
http://apps.magicjudges.org/forum/topic/4555/

Generally so long as players can agree on a randomized pick method for cards, most methods work fine. Most common method I've seen is assigning cards a number then rolling a die.