Showing posts from March, 2011

Issues with Crowdsourced Data Part 2

A recent guest Beneblog explains why we believe a correlation found between SMS text messages and building damage by researchers was not useful. Some of the questions we received made us realize we need to be clearer about why this is important. Why did we bother analyzing this claim? Why does it matter? Thanks to Patrick Ball, Jeff Klingner and Kristian Lum for contributing this material (and making it much clearer).

We’re reacting to the following claim: “Data collected using unbounded crowdsourcing (non-representative sampling) largely in the form of SMS from the disaster affected population in Port-au-Prince can predict, with surprisingly high accuracy and statistical significance, the location and extent of structural damage post-earthquake.”

While this claim is technically correct, it misses the point. If decision makers simply had a map, they could have made better decisions more quickly, more accurately, and with less complication than if they had tried to use crowdsourcing…

Crowdsourced data is not a substitute for real statistics

Guest Beneblog by Patrick Ball, Jeff Klingner, and Kristian Lum

After the earthquake in Haiti, Ushahidi organized a centralized text messaging system to allow people to inform others about people trapped under damaged buildings and other humanitarian crises. This system was extremely effective at communicating specific needs in a timely way that required very little additional infrastructure. We think that this is important and valuable. However, we worry that crowdsourced data are not a good data source for doing statistics or finding patterns.

An analysis team from European Commission's Joint Research Center analyzed the text messages gathered through Ushahidi together with data on damaged buildings collected by the World Bank and the UN from satellite images. Then they used spatial statistical techniques to show that the pattern of aggregated text messages predicted where the damaged buildings were concentrated.

Ushahidi member Patrick Meier interpreted the JRC results as suggesti…

Exciting open access project in Vancouver!

I just spent a couple of days in Vancouver with the team at the Public Knowledge Project, a terrific example of an open source social enterprise. Their largest project is Open Journal Systems, software for running a scholarly journal. It takes an editor through the entire process of operating and publishing a journal, with a heavy emphasis on open access journals (where the articles are freely available to everybody from the moment they are published).

Amazingly enough, more than 8500 journals are published with OJS, with institutions mainly running their own servers. An exciting development is the recent offering of hosting services (through the help of PKP's main partner university, Simon Fraser U. of Vancouver), so that a new journal can be launched without even needing its own home server. A major set of OJS's users are from the developing world: the tools really put the power of expanding knowledge in the hands of scholars!

One metric that made a real impression: OJS u…