How could I motivate people to join a community and write articles on a collaborative blog?

It depends on the topic and purpose of the blog. A common purpose can really motivate a group of people to come together to do something. But of course it isn't easy to get commitment (especially at the beginning), so it'll probably take some time. At the moment I am managing SEA Youth Say So (http://seayouthsayso.com), an online magazine on Southeast Asia powered by young Southeast Asians. The idea is to get more young Southeast Asians to brush up on their writing skills, to feel more empowered to express themselves and their views, as well as to encourage more collaboration and networking. Of course, the bonus is that we also get to provide the rest of the world with a glimpse into the region! Because this is really quite specific (despite our large variety of categories), we do attract contributors who believe in the cause. We have a fairly dedicated team of contributors, but because everyone has to do this on a voluntary basis it can sometimes be difficult to keep coming up with steady new content. For example, in this month of December with everyone busy tying up loose ends, getting ready for Christmas, going away on holiday, we don't really have new content at the moment. But the idea is to keep on plodding on, to continue to engage more people and network and attract more readers, and with that more contributors. What we need is to reach a critical mass where at any given point there is a contributor with an article, instead of having to depend on the same few people in each country to constantly be coming up with articles.

In this instance shouldn't the topic/subject of the blog/site drive content?  Is there enough interest in the topic to generate content?  If you're all talking about your love of moldy socks there'd only be so many people interested in the topic, and from there only so many interested people - who know how to write - interested in the subject.  From my experience - people will write about anything - it's when you start thinking about quality that you'll have to start thinking about paying individuals. I'd imagine that you would also run into problems with the voting function as well - Threadless has thousands of active members within that community - if someone were to create a blog post how would the voting process proceed, and even then would it be overseen by a moderator?  But that's semantics.

This seems to be a twist on the Threadless t-shirts model, no? Not that that's a bad thing I'm simply noting that you might want to study them a bit. With that said, it might make sense to produce something other a blog posting. My reasoning being, that's something most people can do for themselves already. I'm really not sure how you can sex that up to the point of inspiring people. Getting a brand to that level of prestige is a lot of time and effort. What if your output was a quarterly (?) "magazine. What if you sold it via (for example) MagCloud? What if you injected a design component into your "contest" as well?  You could then pay based on sales volume of a given issue. Which would also incent your winner to promote the final product. Producing a physical magazine this way might be interesting. In theory you could sell adverting as well, or at least sign up underwriters/sponsors.

Pay them 1$ per word with the possibility to earn +1$ per word when the post reaches 500, 1000, 1500 words ;)

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