Equitability and dominance in online forums: an ecological approach Jon Rosewell EATING, 13 th November 2008 Dept of Communications and Systems Faculty of Mathematics, Computing and Technology

The few and the many… Participation in forums is very variable –a few students post many messages –many students post a few messages

It seemed a good idea at the time… A relatively painless way of analysing FirstClass forums Looking at patterns of messages, not content –quantitative, not qualitative Postings only, not ‘readings’

What is the point? Analyse past forums –make sense of what went on Relate to structural features –how to design the perfect forum Dashboard approach –monitor the health of forums

Forums included in study Course-based: moderated, not tutors Large: students Mainly 10 pt, 10 week intensive courses Peer support Varying purpose: chat, discussion, help, … Only some presentations analysed 4 courses, 36 forums, 3000 posters, posts

The few and the many (again) Robin Mason: ‘Rule of thirds’ –1/3 post many, 1/3 post few, 1/3 lurk read Or should it be: –posters, readers, phantoms? Or for posters: –post many, post some, post one or two Actually a bit more subtle…

All the data you want

Do you want to see it again?

Do patterns vary?

Ecological analogy Communities often composed of dominant species plus a long tail of rare species Biodiversity –a statistic of academic and practical interest

Diversity indices How to measure diversity? –simple species count risky because of long tail –dominance should count against diversity Diversity indices try to capture both: –richness (species count) –equitability (relative abundance of species)

Shannon’s index where: Stotal number of species (participants) p i proportion of i th species (proportion of total postings)

Ecological stories

From May (1975) Patterns of species abundance and diversity, pp in Cody & Diamond Ecology and Evolution of Communities, Harvard University Press

Shorrocks Genesis of Diversity after Lack (1947) Darwin’s Finches Pianka (1981) ‘Competition and niche theory’ in May Theoretical Ecology

From Whittaker (1972) Evolution and Measurement of Species Diversity, Taxon, 21, pp

Mark Newman Power laws, Pareto distributions and Zipf’s law Contemporary Physics, 46, cmplxsys899/powerlaws.pdf

State of play No simple underlying model –Not geometric: not straight on log-linear plot –Not broken stick or log-normal: not sigmoid –Not power law: not straight on log-log plot So use diversity index as summary

Other possible analyses Thread lengths Starters & finishers Groups Readers etc…

Is it useful? At least in subset here, patterns of participation seem remarkably consistent, so: –doesn’t seem to tell us much about existing forums –no clues as to what to do differently next time Dashboard not likely to be much help –although simple measures might (rate of posting…) Moderators –offer quicker route into feel of conference –can intervene more rapidly –skilled moderation more useful than statistics!

Jon Rosewell The Open University Walton Hall Milton Keynes MK7 6AA

The fruitees

The fruitees – how many readers