Some thoughts on group selection
Rather than the usual pseudo paper review, I have some thoughts written during an otherwise uninspiring talk that ran overtime by 30 mins.
Group selection is a highly useful concept which makes a lot of evolutionary sense. In this way groups with cooperative tendencies can outcompete groups with a tendency to defect. While the individual group member isn't doing the optimal thing, the group as a whole performs much better.
One thing I feel is vital in an agent society is that agents should be able to change their groups and their behaviour as they (or their creator/potential human controller) see fit.
Tags as described in some earlier entries create implicit group selection, where groups are not explicitly formed but come about by the agents effectively distrusting anyone with sufficiently different "genes". Maybe looking at explicit group selection would be a good idea as an agent trying to cheat can probably abuse such an implicit group selection criteria if they want to anyway.
One reason I like the idea of group selection is that everyone wants groups to exist. Cooperators want groups to exist so that they can prosper peacefully with other cooperators and try to keep the defectors out. Defectors want groups so that they can try to invade the groups - without groups or some similar notion everyone will end up defecting, which nobody ever wants. So this is something that should be a popular choice for everyone. I have ignored any other "impure" strategy here, for completeness something more should be discussed.
An important question I need to ask is if there are other theories which compete with group selection. I have a feeling there is because from at least earlier papers/books on the topic of group selection it sounds like it's deemed to be a controversial view. Note to self is to look this sort of thing up more thoroughly.
There are some problems I have with group selection though, before discussing its value or implementation in different arenas any further. One problem is that in many cases it just doesn't matter whether everyone cooperates, so there isn't a strong need for this. An example given in Beenen et al 2004 (though they cite earlier sources for each figure) is that of the Gnutella file sharing network, where 10% of users share 87% of the files, while 2/3 of users don't share any files. Yet it is still considered successful for all concerned, if the freeloaders were driven off it would be far less successful at achieving its goals, in my opinion. The freeloaders don't intend to share files regardless, for reasons external to benefits gained from the network. The work on group selection in this area by Hales 2004 might still be effective though, despite the holes I mentioned previously.
In other cases, group selection isn't such a great idea because the whole point of the system is that everyone is contributing to a whole, and it's the number of participants that makes the system work. Moving to a group based selection would somewhat devalue the usefulness of the system, potentially. In this category I put such systems as eBay or recommender sites that use social networking to get reviews and data on every movie ever made or similar. Here cooperation is very imporgant, but so is participation and everyone being available as a potential trading partner. Reputation based systems for keeping defectors at bay seem more applicable in these areas.
Where does that leave group selection in my mind as a motivator for good behaviour in an agent society? It's probably most useful in a situation where there's competition for resources - the kinds of situations where an evolutionary model makes the most sense in the first place, I suppose.
Gerard Beenen, Kimberly Ling, Xiaoqing Wang, Klarissa Chang, Dan Frankowski, Paul Resnick, Robert E. Kraut - Using Social Psychology to Motivate Contributions to Online Communities
Proceedings of ACM CSCW 2004 Conference on Computer Supported Cooperative Work
David Hales - From Selfish Nodes to Cooperative Networks - Emergent Link-based incentives in Peer-to-Peer Networks
Proceedings of the Fourth International Conference on Peer-to-Peer Computing, 2004
Group selection is a highly useful concept which makes a lot of evolutionary sense. In this way groups with cooperative tendencies can outcompete groups with a tendency to defect. While the individual group member isn't doing the optimal thing, the group as a whole performs much better.
One thing I feel is vital in an agent society is that agents should be able to change their groups and their behaviour as they (or their creator/potential human controller) see fit.
Tags as described in some earlier entries create implicit group selection, where groups are not explicitly formed but come about by the agents effectively distrusting anyone with sufficiently different "genes". Maybe looking at explicit group selection would be a good idea as an agent trying to cheat can probably abuse such an implicit group selection criteria if they want to anyway.
One reason I like the idea of group selection is that everyone wants groups to exist. Cooperators want groups to exist so that they can prosper peacefully with other cooperators and try to keep the defectors out. Defectors want groups so that they can try to invade the groups - without groups or some similar notion everyone will end up defecting, which nobody ever wants. So this is something that should be a popular choice for everyone. I have ignored any other "impure" strategy here, for completeness something more should be discussed.
An important question I need to ask is if there are other theories which compete with group selection. I have a feeling there is because from at least earlier papers/books on the topic of group selection it sounds like it's deemed to be a controversial view. Note to self is to look this sort of thing up more thoroughly.
There are some problems I have with group selection though, before discussing its value or implementation in different arenas any further. One problem is that in many cases it just doesn't matter whether everyone cooperates, so there isn't a strong need for this. An example given in Beenen et al 2004 (though they cite earlier sources for each figure) is that of the Gnutella file sharing network, where 10% of users share 87% of the files, while 2/3 of users don't share any files. Yet it is still considered successful for all concerned, if the freeloaders were driven off it would be far less successful at achieving its goals, in my opinion. The freeloaders don't intend to share files regardless, for reasons external to benefits gained from the network. The work on group selection in this area by Hales 2004 might still be effective though, despite the holes I mentioned previously.
In other cases, group selection isn't such a great idea because the whole point of the system is that everyone is contributing to a whole, and it's the number of participants that makes the system work. Moving to a group based selection would somewhat devalue the usefulness of the system, potentially. In this category I put such systems as eBay or recommender sites that use social networking to get reviews and data on every movie ever made or similar. Here cooperation is very imporgant, but so is participation and everyone being available as a potential trading partner. Reputation based systems for keeping defectors at bay seem more applicable in these areas.
Where does that leave group selection in my mind as a motivator for good behaviour in an agent society? It's probably most useful in a situation where there's competition for resources - the kinds of situations where an evolutionary model makes the most sense in the first place, I suppose.
Gerard Beenen, Kimberly Ling, Xiaoqing Wang, Klarissa Chang, Dan Frankowski, Paul Resnick, Robert E. Kraut - Using Social Psychology to Motivate Contributions to Online Communities
Proceedings of ACM CSCW 2004 Conference on Computer Supported Cooperative Work
David Hales - From Selfish Nodes to Cooperative Networks - Emergent Link-based incentives in Peer-to-Peer Networks
Proceedings of the Fourth International Conference on Peer-to-Peer Computing, 2004
posted by Rowan at
2:25 PM
2 Comments:
Not about groups at all, but thought you might be interested :)
http://www.cimt.plymouth.ac.uk/journal/meyer.pdf
By
Anonymous, at 3:04 PM
Yeah, well aware of that stuff - it's pretty interesting. I was going to say groovy, but it's sort of disappointing that a voting system can't be "perfect". At least it explains why every country has a different voting system and there's something bizarre about each of them. For the record I'm all for Australia's compromise over the other countries whose voting systems I'm aware of.
I'll probably find myself talking about voting and other group decision mechanisms for agents sometime soon. There's a couple of papers about that in my "to read over properly and possibly discuss" pile.
By
Rowan, at 3:11 PM
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