Bricolage is a podcast for makers, made in the united kingdom by dominic morow with new episodes more or less every week!

Engine of More: Dunbar's Number

Engine of More: Dunbar's Number

This writing is about how large or how small a hackerspace community should be. This post is very much a work in progress and I don’t draw a lot of conclusion. However in general my hypothesis is that effective hackerspace communities should be no larger than 200 active members. Size of space does have some bearing on this, but this idea is much more about the size of the community regardless of the size of the space, assuming the space can handle that number.

Prof. Robin Dunbar is a British Anthropologist, Evolutionary Psychologist and specialist in primate behaviour, you can read extracts from his work Grooming, Gossip, and the Evolution of Language on Google Books. Dunbar hypothesised, based on a calculation of the number of acquaintances a primate could reasonably be expect to recall as intimate friends. This calculation using a number of averages and a sort of bell curve of results based on brain size and other factors, determined an ideal number of about 150 relationships as being the ideal number for primates to handle.

In the above linked chapter of Grooming, Gossip, and the Evolution of Language, Dunbar illustrates that in many grouping 80 to around 200 people is considered a good number. This includes church congregations (CofE ideal congregation size is considered to be 200), army companies (British Army Companies are around 130 strong) and the number of people, on average, an individual feels able to join for a drink, uninvited, should they bump into each other down the pub (anywhere from about 80 to 200 people on average).

And so what of hackerspaces. Am I suggesting a hackerspace should have only 150 people involved with it? Yes and no. I don’t know the answer to this question, but I do have a suspicion that 150 active members* is about the right number. With-in most shared workshops, there are of course, a number of different levels of participation.

I want to talk about Active & Supportive membership.

What is supportive membership? A common recurrence I hear and read about is a level of participation that is something like patronage. This is where a member pays membership dues, but has little to no intention of using the space, they likely are more inclined to be a supporter of the space. They like the idea of a space generally and want to support one space over another in particular. It is supposed, though not confirmed, that a part of that support is a feeling of belonging, on an equal footing as any other member in the space with the same entitlements to participate.

What is an active member? By this I mean someone attending regularly maybe 1 or more times weekly, depleting the resources of the space such as electricity and often actively engaging in other activities within the organisation such as group meetings, volunteering or performing a role within the structure. Sometimes these members are under engaged, sometimes over engaged, but what they have in common is regular usage and attendance of the space.

I’ve noticed that often, the people that engage with the online community part of a hackerspace are not always the same people who engage with the actual space physically. I’ve noticed in some hackerspace organisations a real disconnect between the people in the space and this online-virtual space. Whilst often this is unimportant, on occasions I’ve seen the virtual space as being the dominant in terms of decision making and general governance of a hackerspace. That’s probably a wider thing I need to look at.

The physical size of a space, is of course, very important in the understanding of the number of members a space can really accommodate. To take a smaller space as an example, Lime House Labs, a new hackerspace project in East London, has only 25.7m Sq of space that is technically their own to manage. As has been mentioned earlier they have a membership limit of 25 members. I’ve read in various places, that the most people you could have standing in a space like that would be around 100 people, it’d be very cramped and you could not do a lot of hacking. On average, for city living, it’s suggested that a single person needs a minimum of 25m Sq or living space. So I hope you get the idea of the size of that space. Even with these limitations, it’d not be optimal to have the whole membership turn up to use the space for making projects.

Perhaps a rule of thumb can be worked out, that understands what the optimal number of active vs supportive members could be and various bit of data analysis done to understand how the membership stands in terms of active vs supportive. I’d like it if the formula was as simple as 1 member per sq foot or a similarly easy number could be established.

Of course Dunbar’s number is often criticised, other anthropologists talk about tribal sized based on the absence or presence of agriculture and are not so sure that the primitive primate brain is altogether important in this aspect. It used to be a favoured example of social networks on line, that about 150 was the average, but on Facebook (368), linkedIn (erm?) and twitter (208) those numbers aren’t especially representative of those with active accounts and are prone to skewing based on a perceived value of a person with lots and lots of friends and followers, verses those with none.

In conclusion I’d strongly consider 150 to 200 as being the number of active members in a community, and of course the same in space of around 200 Sq M can accommodate. This does not mean that I’d encourage more members than 200 in a larger space. or fewer in a smaller space.

As a little flight of fancy, let’s consider a space of 150 active members each paying £25 per month as a membership due. This gives £3750 per month membership income an ideal. The rental on a unit of around 150sq M in my part of the world is generally between £1200 and £2000 per month, plus bills etc. This gives you a good working overhead for a space of that size. No doubt I could develop some webpage with sliders that would scale all these numbers up and down?! All of these numbers are highly open to debate and adjustment based on lots of factors of course.

Today’s thumbnail is 35L “Really Useful Boxes” at the Cambridge Makespace in the UK University town of Cambridge. It is one of the better run examples of a shared workshop in the UK.

Rob Ives Episode.13

Rob Ives Episode.13

Engine of More: Glossary

Engine of More: Glossary