Coen de Groot [coen@...] wrote:
> In "The Tipping Point", Malcolm Gladwell explains about
> the magic number 150. There is apparently a lot of evidence
> that humans have evolved to function well in communities of
> up to 150 people. Above that number we quickly loose track
> of who is who and who knows what
>
> What our your thoughts on ideal numbers and on splitting
> up an email discussion group into subgroups? Perhaps there
> are technical solutions that give the best of both worlds?

What you are talking about is something called the "Dunbar Number". I have
written extensively about it in my blog.

"2004-03: The Dunbar Number as a Limit to Group Sizes"
http://www.lifewithalacrity.com/2004/03/the_dunbar_numb.html -- this is my
first essay on the Dunbar Number, where I discuss the original science
behind the Dunbar Number, how it has been somewhat misinterpreted as it has
been popularized by Gladwell, et al, as the 150 number really only applies
to survival groups. That to support a group size of 150 requires a huge
amount of 'social grooming' that more casual groups can't affort. I continue
with my own hypothesises on the sizes of groups, and predict that there are
at least two nodal sizes of non-survival groups, one peaking at 7-8, the
other at 40-60. I then show some evidence based on numbers from an old
online game "Ultima Online" to substantiate the 40-60 number. There are also
some really good commentary and trackbacks at
http://www.lifewithalacrity.com/2004/03/the_dunbar_numb.html#comments
including how the Dunbar Number applies to terrorist organizations at
http://globalguerrillas.typepad.com/globalguerrillas/2004/03/what_is_the_opt
.html .

"2005-02: Dunbar Triage: Too Many Connections"
http://www.lifewithalacrity.com/2005/02/dunbar_triage_t.html -- An essay on
the limited number of connections that you can meaninfully maintain, how
social networking services often make the problem works, how various
cultural strategies that evolved to allow this limit to be increased, some
possible technological solutions, and some conclusions and open questions.

"2005-03: Dunbar, Altruistic Punishment, and Meta-Moderation"
http://www.lifewithalacrity.com/2005/02/dunbar_triage_t.html -- In my
original essay on the Dunbar Number I hypothesize a nodal optimal group size
of 6-8, but was only able to offer anecdotal evidence to support it. This
essay shows some possible reasons why this nodal size exists, from some
research in game theory on 'altruistic punishment'. The premise of
altruistic punishment is to allow members of a group to punish others for
non-conformance, but only at some cost to the punishers. This still is not
empirical evidence, as it is only based on computer simulations, but very
interesting. I also discuss how these findings on altrustic punishment apply
to moderation and meta-moderation of online groups.

"2005-07: Cheers: Belongingness and Para-Social Relationships"
http://www.lifewithalacrity.com/2005/07/cheers_belongin.html -- Some
discussion of fundemental human need to 'belong' and how there exists some
junk social companionship called "para-social relationships". I raise the
question of whether para-social relationship impact the Dunbar Number.

"2005-08: Dunbar & World of Warcraft"
http://www.lifewithalacrity.com/2005/08/dunbar_world_of.html -- In my
original Dunbar Number essay I offer some evidence from the online game
Ultima Online. Some more recent data from the online game World of Warcraft
offer some more empirical data to substantiate both the 40-60 peak as well
as some possible evidence for the 6-8 peak. However, it also raises some
other questions.

"2005-10: Dunbar Number & Group Cohesion"
http://www.lifewithalacrity.com/2005/10/dunbar_group_co.html -- My most
recent essays draw from some wonder analysis of groups in the online game
Worlds of Warcraft. Applying some analysis to mapping the social networks of
this online game show some intriguing evidence of differences in the group
cohesion of different sizes of groups. Futhermore, it offers even more
evidence of the two nodal sizes from my original Dunbar Number essay.

There is also a excellent blog entry by blogger Adam MacDonald that
summarizes the major points of my essays on the Dunbar Number and how they
apply to social network software at
http://tidehorizon.blogspot.com/2006/05/do-shy-ever-win-social-networking.ht
ml

-- Christopher Allen

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.. Christopher Allen Alacrity Management ..
.. <ChristopherA at AlacrityManagement.com> 1563 Solano Ave Ste 353 ..
.. blog: www.LifeWithAlacrity.com o510/649-4030 Berkeley, CA 94707 ..