Comments on: What is Dunbar’s Number?

By: Gregy

Gregy — Fri, 20 Jun 2008 23:02:47 +0000

Jeff - We at LinkedIn (click my name for more on my role there) obviously think about these issues on a regular basis. We recommend that tworzenie stron only accept connection requests from people with whom they already have a relationship or for whom they would at least feel comfortable saying something positive if asked, say, as part of a reference check. LinkedIn should be an extension of your real-world relationships, not a substitute.

By: johny

johny — Wed, 28 Feb 2007 11:22:38 +0000

You know, one of the slightly unsatisfactory things about sites like LinkedIn is the inability to rate a connection. For example, Tworzenie stron www Iâ€™ve got a connection to some guy who worked at BroadVision at about the same time I did, but I donâ€™t know him particularly well.

By: Tim

Tim — Wed, 14 Feb 2007 19:36:46 +0000

Mark… If I remember correctly, the company you’re thinking of (Gladwell’s example), is Goretex.

Tim.

By: Christopher Fahey

Christopher Fahey — Sat, 27 Jan 2007 22:52:37 +0000

A friend of mine who worked on a very major social networking product told me that they had actually used the 150 cap for their users’ connections lists — at least initially. What they found was that, while Dunbar’s number is valid for most people, it completely demolished the impact of “superconnectors”, who are the ultra-well-connected people who make up the real power base of social networks. Superconnectors have hundreds of connections — real connections, people they know. They exist in the real world, too, not just virtually, and they keep our societies together.

IMHO, Dunbar’s Number sounds even more like the Magical Number 7 than you seem to suggest: That is, it’s almost completely useless and irrelevant to real-world design decisions.

By: Josh

Josh — Wed, 17 Jan 2007 14:45:05 +0000

Michael…thank for the link! Looks like a great resource…

By: Michael Chui

Michael Chui — Wed, 17 Jan 2007 09:53:32 +0000

The common misconception about the Dunbar Number is that it applies to your own system: people shouldn't design systems assuming that 150 will be the cap. More likely, a tight social network will end up closer to 25 or 50. This is the oldest and best post I know on the subject: Life with Alacrity: The Dunbar Number as a Limit to Group Sizes. I also found this post "Great Social Networking Posts," but I couldn't locate the one I was looking for, which slashed the optimal numbers to 12, 50, and 150. It was by someone else in the blogosphere... it's been too long.

By: David Sanford

David Sanford — Wed, 17 Jan 2007 05:29:29 +0000

First of all, thank you Joshua for the interesting post and for your blog more generally (I’ve been an active reader for some time now).

Jeff – We at LinkedIn (click my name for more on my role there) obviously think about these issues on a regular basis. We recommend that people only accept connection requests from people with whom they already have a relationship or for whom they would at least feel comfortable saying something positive if asked, say, as part of a reference check. LinkedIn should be an extension of your real-world relationships, not a substitute.

We’ve also been thinking about ways to add context to connections on LinkedIn, both privately and publicaly, and would be open to your suggestions.

Finally, you can always disconnect from people with whom you no longer have a relationship.

Looking forward to more great thoughts on this blog,

Dave

By: Mark

Mark — Tue, 16 Jan 2007 19:54:44 +0000

Dunbar’s number is very interesting in that it applies to a wide range of organizations from a number of different perpsectives. For example, John Robb has applied the concept to terrorist networks:
http://globalguerrillas.typepad.com/globalguerrillas/2004/03/what_is_the_opt.html
And I believe Malcolm Gladwell explored the concept in The Tipping Point (it’s been a while since I read that, but I think he mentioned something about a company that would limit their offices to 150 people).

With respect to social web apps, I think the interesting thing is how some of them are able to bypass the limit to produce a useful information resource. For example, del.icio.us aggregates bookmarks and tags in such a way that many more than 150 people can contribute to the resource without experiencing the degradation that Dunbar’s number suggests.

By: Jeff Watkins

Jeff Watkins — Tue, 16 Jan 2007 15:11:33 +0000

You know, one of the slightly unsatisfactory things about sites like LinkedIn is the inability to rate a connection. For example, I’ve got a connection to some guy who worked at BroadVision at about the same time I did, but I don’t know him particularly well. So when it comes to introductions, the system shouldn’t really count on that connection, because it’s tenuous at best.

Of course, I _could_ make an effort to strengthen the connection. That would probably be mature and forward thinking on my part…

By: ~bc

~bc — Tue, 16 Jan 2007 14:15:57 +0000

Should sites like MySpace have an upper limit of friends you can add? Sort of like your top four/eight/16, but less so… it would force you to actually think instead of just “thanks for the add…”