
Winning White Elephant Gift Exchanges Using Game Theory - aaronbrethorst
http://fivethirtyeight.com/features/white-elephant-yankee-swap-game-theory/?ex_cid=538twitter
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murbard2
The rules, as stated, make the game particularly uninteresting.

I would suggest instead doing some type of Colonel Blotto game. For instance:

Give each player 1000 points^. Points can be used to secretly bid on gifts
and/or on players. When the bids are revealed, each gift is temporarily
assigned to the highest bidder, _but then_ , immediately re-assigned to the
highest bidder on that player. So if you want to get a specific gift, not only
should you bid on that gift, but you should also bid on yourself to avoid the
gift being reassigned. Or you could put a high bid on someone you think will
snatch that gift.

^ or a suitably large number to avoid issues of divisibility.

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strictnein
It can be interesting because you've typically spent the previous couple of
hours drinking.

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murbard2
Not if you're in the company of people who like intractable game theory
problems.

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TallGuyShort
* you're. Oh... Oh I see your point.

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murbard2
(thanks, fixed)

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rtkwe
This doesn't seem to cover the rule I've always played with where the first
person to pick gets to swap at the end of the game with anyone. Is that not a
common rule?

Under that 1 is the best (can always get whatever gift they want) but they
usually get stuck with a mediocre present until the very end.

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strictnein
That's Footnote #3 in the article:

> "There are lots of variations on these rules, such as capping the number of
> times a gift can be stolen or letting the person who went first take another
> turn at the end."

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rtkwe
Ah serves me right for skipping them. Wonder how those variations are spread
out. Do they cluster geographically or is it more localized to families?

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colin_mccabe
No big surprises here... knowing the distribution of prizes helps a lot, like
you might expect. I was a bit surprised that being the first player was better
than being the second in their modeled game (I figured later was always
better). The configuration is fiddly enough that I wonder if a slightly
different configuration would remove that advantage.

It would be more interesting if someone could come up with a "fairer" version.

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gragas
This seems really trivial. There always has to be at least one gift that is of
average value or greater. Also, there probably aren't a large number of gifts
in white elephant gift exchanges, so it's not so safe to generalize the
average value of the opened gifts to the entire population.

I was really hoping for a more rigorous proof and a more non-intuitive
strategy.

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Vraxx
Seriously.. They tried to complicate it by bringing expected value, which
isn't terribly complicated even still, but the whole strategy can be summed up
with the following. Do you like any of the gifts here more than than the
"average" gift, if so, steal. Is this really news? I appreciated the sentiment
of this post, but not the content.

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helipad
My wife took part in one of these.

She chose to "steal" a gift, whereby the owner said "no", quickly realizing
the participant was serious.

And that, folks, is where grudges come from.

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schwap
I think the model needs to be expanded to include the popular "maximum steal
count" rule, that a gift can only be stolen, say, 2 times at which point it
becomes "un-stealable".

EDIT: d'oh, should've read the code. This is accounted for.

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Zikes
I recently read a theory that the origin of the name "white elephant" is due
to an Asian ruler gifting albino elephants to people he did not like, as they
were very high maintenance and would become a financial burden.

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at-fates-hands
Sounds about right considering the Wiki page states something similar:

 _The term white elephant refers to a gift whose maintenance costs exceed its
usefulness. While the first use of this term remains a matter of contention
among historians_

[https://en.wikipedia.org/wiki/White_elephant_gift_exchange](https://en.wikipedia.org/wiki/White_elephant_gift_exchange)

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kitwalker12
doesn't it kind of translate to always steal unless you don't want to steal

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bmh100
You have the essence of the strategy:

Unless there is a limit on the number of times a gift can be stolen, always
steal a gift valued above the average of all currently opened gifts.

Limits on the number of times a gift can be stolen are popular, making the
strategy more useful. In that case, you should open a gift if none of the
available gifts are above average.

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JustSomeNobody
I win by not playing.

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ibmthrowaway218
ITYM:

    
    
      A STRANGE GAME.
      THE ONLY WINNING MOVE IS
      NOT TO PLAY.

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tunesmith
I'd just be tempted to steal the least valuable gift to make it less stressful
for myself and more valuable for everyone else.

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pasbesoin
> Of course, as with any gift exchange, the real goal is to win.

And that's where these things lose me. Turning a community event into a
competitive event.

And yet, in many places, if you don't participate, you are viewed as shunning
the community.

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ufo
Sounds like you skipped the footnotes.

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pasbesoin
I saw the footnotes, although admittedly quickly.

I see I'm downvoted, but I was serious in my comment. In the scenario
described, as well as in a significant fraction of other "social" behavior
including in work settings, I encounter a lot of competition. And I am one for
whom such competition simply is not fun.

I guess if I consider it a bit more, a lot of it seems to be centered around
attitudes of "zero sum gain"; someone must "win", and correspondingly others
much "lose".

By contrast, I am... oh, I forget the corresponding terminology, but I prefer
social gatherings that are a "net gain."

Another area where I find this: Sports. For sports with teams and/or
competition, you need more than one participant in order to have the game. Yet
instead of enjoying the game and thanking them for their participation, too
often there seems to be an excessive amount of focus on "winning" and on
"ragging on" or criticizing (actually, verbally abusing) the losers.

I enjoy participating and it is thrilling to win. But I do NOT enjoy "ragging
on" nor berating the loser.

I guess I'm taking this secret santa thread/response too far. But I've
observed that I'm not the only one. There is a greater than miniscule fraction
of the population who does not enjoy such things, nor a lot of sports, because
during this event meant to strengthen social cohesion, once again they find
the group picking winners and losers. And some of them aren't very nice
towards the losers -- even when they cloak this behavior in a facade of "good
cheer."

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braythwayt
You are exactly right. Humans are social creatures, and the "winning and
losing" in such events is governed by far, far more than the "expected value"
of the gift.

Excessive "ragging" is a net loss, often for the entire group. Chemistry is
tricky, and a game like this can get toxic, quickly. As can any game. That's
why people often play games, it's a very effective way to suss out people's
true nature. Doesn't matter whether it's White Elephants, Bridge, or Golf.

One excellent strategy is to deliberately pick a lame gift and make up a funny
story about why you want it. For example, if absolutely nobody wants the lime
green monokini, take it and announce that you intend to hire a houseboy and
make him wear it.

Presto, everyone is laughing and you are off the hook for winning without
dampening the fun of those who want to play the game for keeps.

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pasbesoin
Thank you for that suggestion. :-)

