Upcoming lecture: Denis Helic (TU Graz)

   13th November 2018

Date: 13th November 2018, 4PM

Venue: HAS CSS RECENS, Meeting Room (T.140)

Address: H-1097 Budapest Tóth Kálmán street 4. T building 1st Floor Room 40.


Tend to the User Core, Don't Neglect the Casuals: A Recipe for Growth of 
Q&A Web Communities

Millions of users on the Internet discuss a variety of topics on 
Question-and-Answer (Q&A) instances. However, not all instances and 
topics receive the same amount of attention, as some thrive and achieve 
self-sustaining levels of activity while others fail to attract users.
It is imperative to not only better understand but also to distill 
deciding factors and rules that define and govern sustainable Q&A 

To that end, we extract, model and cluster user activity-based time 
series from selected Q&A instances from the Stack Exchange network to 
characterize user behavior. We find distinct types of user activity 
temporal patterns, which vary primarily according to the users' activity 
frequency.  Moreover, we distill temporal dynamics of community activity 
and thereby identify key factors leading to success or failure of 
communities. Further, we compare groups of StackExchange communities of 
different topical focuses, such as STEM and humanities.

We find that growing communities exhibit both a small core of power 
users reacting to the community as a whole, and many casual users 
strongly interacting with other casual users, suggesting community 
openness towards less active users. Further, we find that communities in 
the humanities are centered around power users, whereas in STEM 
communities activity is more evenly distributed. With our analysis,we 
provide insights for practitioners to quantitatively assess evolution 
and the activity potential of Q&A communities.