Community evolution on Stack Overflow

ArXiv, 2018

Stack Overflow (SO) is the most popular question-and-answer website for software developers, providing a large amount of code snippets and free-form text on a wide variety of topics. Like other software artifacts, questions and answers on SO evolve over time, for example when bugs in code snippets are fixed, code is updated to work with a more recent library version, or text surrounding a code snippet is edited for clarity. To be able to analyze how content on SO evolves, we built SOTorrent, an open dataset based on the official SO data dump. SOTorrent provides access to the version history of SO content at the level of whole posts and individual text or code blocks. It connects SO posts to other platforms by aggregating URLs from text blocks and comments, and by collecting references from GitHub files to SO posts. In this paper, we describe how we built SOTorrent, and in particular how we evaluated 134 different string similarity metrics regarding their applicability for reconstruc...

2014

Historically, mailing lists have been the preferred means for coordinating development and user support activities. With the emergence and popularity growth of social Q&A sites such as the StackExchange network (e.g., StackOverflow), this is beginning to change. Such sites offer different sociotechnical incentives to their participants than mailing lists do, e.g., rich web environments to store and manage content collaboratively, or a place to showcase their knowledge and expertise more visibly to peers or potential recruiters. A key difference between StackExchange and mailing lists is gamification, i.e., StackExchange participants compete to obtain reputation points and badges. Using a case study of R, a popular data analysis software, in this paper we investigate how mailing list participation has evolved since the launch of StackExchange. Our main contribution is assembling a joint data set from the two sources, in which participants in both the r-help mailing list and StackExchange are identifiable. This allows for linking their activities across the two resources and also over time. With this data set we found that user support activities are showing a strong shift away from r-help. In particular, mailing list experts are migrating to StackExchange, where their behaviour is different. First, participants active both on r-help and on StackExchange are more active than those who focus exclusively on only one of the two. Second, they provide faster answers on StackExchange than on r-help, suggesting they are motivated by the gamified environment. To our knowledge, our study is the first to directly chart the changes in behaviour of specific contributors as they migrate into gamified environments, and has important implications for knowledge management in software engineering.

2011 27th IEEE International Conference on Software Maintenance (ICSM), 2011

With the growing number of large scale software projects, software development and maintenance demands the participation of larger groups. Having a thorough understanding of the group of developers is critical for improving development and maintenance quality and reducing cost. In contrast to most commercial software endeavors, developers in open source software (OSS) projects enjoy more freedom to organize and contribute to a project in their own working style. Their interactions through various means in the project generate a latent developer social network (DSN). We have observed that developers and their relationships in these DSNs change continually under the influence of differences in the set of active developers and their changing activities. Revealing and understanding the structure and evolution of these social networks as well as their similarities and differences from other more general social networks (GSNs) is of value to our software engineering community, as it allows us to begin building an understanding of how well the findings from other fields based on GSNs apply to DSN. In this paper, we compare DSNs with popular GSNs such as Facebook, Twitter, Cyworld (a large social network in South Korea), and the Amazon recommendation network. We found, for instance, that while most social networks exhibit power law degree distributions, our DSNs do not. In addition, we also examine how DSNs evolve over time, highlighting how events within a project (such as a release of new software or the departure of prominent developers) impact the makeup of the DSNs, and observe the evolution of topological properties such as modularity and the paths of communities within these networks.

Lecture Notes in Social Networks, 2019

Stack Overflow has become a fundamental resource for developers, becoming the de facto Question and Answer (Q&A) website, and one of the standard unstructured data sources for software engineering research to mine knowledge about development.

Proceedings of the 53rd Hawaii International Conference on System Sciences

Stack Overflow (SO) has become a primary source for learning, how to code, with community features supporting asking and answering questions, upvoting to signify approval of content, and comments to extend questions and answers. While past research has considered the value of posts, often based on upvoting, little has examined the role of comments. Beyond value in explaining code, comments may offer new ways of looking at problems, clarifications of questions or answers, and socially supportive community interactions. To understand the role of comments, a content analysis was conducted to evaluate the key purposes of comments. A coding schema of nine comment categories was developed from open coding on a set of 40 posts and used to classify comments in a larger dataset of 2323 comments from 50 threads over a 6-month period. Results provide insight into the way the comments support learning, knowledge development, and the SO community, and the use and usefulness of the comment feature.

2019 IEEE/ACM 16th International Conference on Mining Software Repositories (MSR), 2019

Stack Overflow (SO) is the most popular questionand-answer website for software developers, providing a large amount of copyable code snippets. Like other software artifacts, code on SO evolves over time, for example when bugs are fixed or APIs are updated to the most recent version. To be able to analyze how code and the surrounding text on SO evolves, we built SOTorrent, an open dataset based on the official SO data dump. SOTorrent provides access to the version history of SO content at the level of whole posts and individual text and code blocks. It connects code snippets from SO posts to other platforms by aggregating URLs from surrounding text blocks and comments, and by collecting references from GitHub files to SO posts. Our vision is that researchers will use SOTorrent to investigate and understand the evolution and maintenance of code on SO and its relation to other platforms such as GitHub.

Proceedings of the 23rd International Conference on World Wide Web - WWW '14 Companion, 2014

In the past few years, Reddit-a community-driven platform for submitting, commenting and rating links and text posts-has grown exponentially, from a small community of users into one of the largest online communities on the World Wide Web. In this paper we study (i) how user submissions have evolved over time and (ii) how the community's allocation of attention and its perception of submissions have changed on Reddit. Our analysis reveals an ever-increasing diversification of topics accompanied by a simultaneous concentration towards a few selected domains that submissions link to. By and large, our investigations suggest that Reddit has transformed itself from a dedicated gateway to the Web to an increasingly self-referential community that focuses on and reinforces its own user-generated image-and textual content over external sources. The results presented in this work are based on an analysis of all submissions to Reddit from 2008-2012 (almost 60 mio posts). To the best of our knowledge, this represents the largest-scale study of Reddit's evolution to date.

Efforts such as Wikipedia have shown the ability of user communities to collect, organize and curate information on the Internet. Recently, a number of question and answer (Q&A) sites have successfully built large growing knowledge repositories, each driven by a wide range of questions and answers from its users community. While sites like Yahoo Answers have stalled and begun to shrink, one site still going strong is Quora, a rapidly growing service that augments a regular Q&A system with social links between users. Despite its success, however, little is known about what drives Quora's growth, and how it continues to connect visitors and experts to the right questions as it grows. In this paper, we present results of a detailed analysis of Quora using measurements. We shed light on the impact of three different connection networks (or graphs) inside Quora, a graph connecting topics to users, a social graph connecting users, and a graph connecting related questions. Our results show that heterogeneity in the user and question graphs are significant contributors to the quality of Quora's knowledge base. One drives the attention and activity of users, and the other directs them to a small set of popular and interesting questions.