# Chimp sharing game experiment seems flawed - How could you design to get meaningful results? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [January 16, 2013, 10:35pm UTC](https://boards.straightdope.com/t/chimp-sharing-game-experiment-seems-flawed-how-could-you-design-to-get-meaningful-results/647434 "2013-01-16T22:35:30Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [January 16, 2013, 10:35pm UTC](https://boards.straightdope.com/t/chimp-sharing-game-experiment-seems-flawed-how-could-you-design-to-get-meaningful-results/647434/1 "2013-01-16T22:35:30Z")
[Article here](http://www.latimes.com/news/science/sciencenow/la-sci-sn-hunger-games-chimpanzees-play-fair-study-pnas-20130114,0,6600749.story?track=rss) How would you design the experiment to fix the glitch described below and make sure both participant chimps are aware of their mutual power to effect outcomes? > [@](#): > > The research, released Monday by the Proceedings of the National Academy of Sciences, used the Ultimatum Game, in which one player (the proposer) has the power to split a reward with another player (the recipient). > > If the proposers can decide how to split the reward unilaterally, they often leave as little as possible for the recipient, keeping the lion’s share for themselves (this is often referred to as the “dictator game”). But in a version called the “ultimatum game,” if the recipient has the power to veto the reward – preventing both players from getting any – the proposer is more likely to offer a 50-50 split . But there’s a glitch > [@](#): > > Here’s the catch, though: Neither the chimps nor the children in this study ever vetoed the offer, even when it was unequal. Thus, it’s not clear the recipients understood that they had the power to influence how much the proposers shared with them. > > So proposing chimps try to play fair with a recipient when they realize they need the recipient to gain a reward – but recipient chimps don’t realize they can use that power as leverage? > > Perhaps it’s just that neither children nor chimps quite grasped the rules, because recipients seemed to express their disapproval in other ways, the authors pointed out. One recipient chimp seemed to express outrage at an unfair share, either spitting water at the proposer or banging against the fence separating them. ---
**Author:** ![shijinn](https://avatars.discourse-cdn.com/v4/letter/s/cc9497/32.png) [@shijinn](https://boards.straightdope.com/u/shijinn)\ **Post date:** [January 17, 2013, 2:23am UTC](https://boards.straightdope.com/t/chimp-sharing-game-experiment-seems-flawed-how-could-you-design-to-get-meaningful-results/647434/2 "2013-01-17T02:23:50Z")
need to know exactly how they carried out the experiment. how did the proposing chimp realise they need the recipient to gain a reward? in any case, my suggestion would be giving the recipient the choice of the split, rather than a veto. that should be easier to catch on than the idea of a veto. ---
**Author:** ![OleOneEye](https://avatars.discourse-cdn.com/v4/letter/o/f14d63/32.png) [@OleOneEye](https://boards.straightdope.com/u/OleOneEye)\ **Post date:** [January 17, 2013, 2:58am UTC](https://boards.straightdope.com/t/chimp-sharing-game-experiment-seems-flawed-how-could-you-design-to-get-meaningful-results/647434/3 "2013-01-17T02:58:00Z")
"So proposing chimps try to play fair with a recipient when they realize they need the recipient to gain a reward – but recipient chimps don’t realize they can use that power as leverage? Perhaps it’s just that neither children nor chimps quite grasped the rules" Is this some kind of a joke? I might expect a 7-year-old human to understand the rules as explained, but is there even a meaningful way to explain the rules to a chimp? Seriously, how would you tell a chimp that it was allowed to “use that power as leverage”? How would you explain rules to a chimp at all? ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [January 17, 2013, 3:20am UTC](https://boards.straightdope.com/t/chimp-sharing-game-experiment-seems-flawed-how-could-you-design-to-get-meaningful-results/647434/4 "2013-01-17T03:20:58Z")
Perhaps children and chimps aren’t as motivated by spite. After all, even when adults play, they gain nothing by refusing the split, but they tend not to accept highly unfair splits. There is no point in it, but there is some motivating factor. It might be that children and chimps are missing the point of the rules because it serves them no purpose. It is in effect the same as not grasping the rules, but not necessarily from a lack of ability to do so. ---
**Author:** ![Speak\_to\_me\_Maddie](https://avatars.discourse-cdn.com/v4/letter/s/58956e/32.png) [@Speak\_to\_me\_Maddie](https://boards.straightdope.com/u/Speak_to_me_Maddie)\ **Post date:** [January 17, 2013, 1:04pm UTC](https://boards.straightdope.com/t/chimp-sharing-game-experiment-seems-flawed-how-could-you-design-to-get-meaningful-results/647434/5 "2013-01-17T13:04:22Z")
The expiriment shows the nature of chimps and children as opposed to adult humans. I don’t understand why it needs to be fixed. The expiriment works. ---
**Author:** ![iamthewalrus\_3](https://avatars.discourse-cdn.com/v4/letter/i/258eb7/32.png) [@iamthewalrus\_3](https://boards.straightdope.com/u/iamthewalrus_3)\ **Post date:** [January 17, 2013, 7:42pm UTC](https://boards.straightdope.com/t/chimp-sharing-game-experiment-seems-flawed-how-could-you-design-to-get-meaningful-results/647434/6 "2013-01-17T19:42:30Z")
> [@shijinn](#): > > need to know exactly how they carried out the experiment. how did the proposing chimp realise they need the recipient to gain a reward? in any case, my suggestion would be giving the recipient the choice of the split, rather than a veto. that should be easier to catch on than the idea of a veto. That’s a different experiment entirely. The ultimatum game reveals that we are not entirely economically rational creatures. After all, the rational response is to take whatever you are offered, as long as its above 0, since that’s better than nothing. The human response is to “punish” the ultimatum-maker, even if it means losing out on your own reward, if the split isn’t sufficiently fair. If you make it a “you cut, I choose”, you no longer have to decide between economically rational behavior and social reinforcing punishment, since you get the most gain for yourself _and_ you punish the unfair split by taking the bigger pile. ---
**Author:** ![thelurkinghorror](https://avatars.discourse-cdn.com/v4/letter/t/7c8e57/32.png) [@thelurkinghorror](https://boards.straightdope.com/u/thelurkinghorror)\ **Post date:** [January 17, 2013, 8:46pm UTC](https://boards.straightdope.com/t/chimp-sharing-game-experiment-seems-flawed-how-could-you-design-to-get-meaningful-results/647434/7 "2013-01-17T20:46:57Z")
The 50-50 outcome assumes that humans and apes operate very logically. We/they don’t. Also people are willing to lose the reward just if it means screwing over someone else. We can realize this isn’t the optimal situation, but are willing to forgo a reward to screw someone else (over), especially if we think negatively about them, they cheat, etc. This impulse might also work the other way. One interpretation is that kids/apes/ape-kids work differently than adult humans in this respect. The way to “fix” this is to do another similar experiment to increase certainty that this is a general effect, or not. Teaching the task to apes: not always easy. You don’t tell them in English, but most animals are trained with conditioning. They play the game in many, many practice sessions, and are rewarded when they make the right choice, and optionally punished for the wrong choice. ---
**Author:** ![shijinn](https://avatars.discourse-cdn.com/v4/letter/s/cc9497/32.png) [@shijinn](https://boards.straightdope.com/u/shijinn)\ **Post date:** [January 18, 2013, 5:06am UTC](https://boards.straightdope.com/t/chimp-sharing-game-experiment-seems-flawed-how-could-you-design-to-get-meaningful-results/647434/8 "2013-01-18T05:06:30Z")
> [@iamthewalrus\_3](#): > > That’s a different experiment entirely. … you are correct. i was mostly reacting to the title, “Do chimps play fair?” without reading up on the Ultimatum game. i was thinking that, for the proposing chimp, he would quickly learn to play fair if it were “you cut, i choose”. a quick glance at the Ultimatum game on Wiki says, “The game is played only once so that reciprocation is not an issue.” if so, i don’t see how you could bring the concept across to chimps in a single trial. > [@TriPolar](#): > > Perhaps children and chimps aren’t as motivated by spite. … they could also be motivated by generosity, i could see a proposing child giving a bigger share of stickers to another to be nice. ---
**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\ **Post date:** [January 18, 2013, 1:34pm UTC](https://boards.straightdope.com/t/chimp-sharing-game-experiment-seems-flawed-how-could-you-design-to-get-meaningful-results/647434/9 "2013-01-18T13:34:45Z")
Give the non-dividing chimp two buttons to press. One button gets the chimp the food; the other button dresses the dividing chimp in a plaid suit with a bow-tie. Or some other punishment for the dividing chimp. That way, the non-divider gets to choose between accepting the share, or refusing the share and punishing the divider.