# Understanding How GitHub Supports
## 3 Method  
To characterize popular curation repositories hosted on GitHub, we collected a dataset of activity logs on GitHub, identified the top curation and software repositories, compared them with top software repositories, and coded the contents of the curation repositories. The dataset was collected from GitHub Archive ([[https://www.githubarchive.org/](https://www.githubarchive.org/)]([https://www.githubarchive.org/](https://www.githubarchive.org/))), which captures a comprehensive GitHub timeline data. GitHub Archive data has been actively used for analysis in academic publications [10; 14; 15; 16]. However, the dataset was influenced by a bug report about a crawler issue on 22 September 2013 ([[https://github.com/igrigorik/githubarchive.org/pull/37](https://github.com/igrigorik/githubarchive.org/pull/37)]([https://github.com/igrigorik/githubarchive.org/pull/37](https://github.com/igrigorik/githubarchive.org/pull/37))), which resulted in a loss of events. For consistency and data quality, we collected 109,782,635 events on 7,079,847 repositories that occurred between 1 October 2013 and 31 August 2014. In order to find the commonalities of the curation repositories that are of interest to others, we selected the ones based on indicators of popularity. Trending repositories are displayed on GitHub by day, week, or month. The trending repositories typically average about 500 stars per repository ([[https://github.com/trending?l=all&since=weekly](https://github.com/trending?l=all&since=weekly)]([https://github.com/trending?l=all&since=weekly](https://github.com/trending?l=all&since=weekly))). Given that a repository that trends can be considered a relatively popular repository on GitHub, we then selected all repositories that had more than 500 stars within a date range. At the same time, many software repositories with more than 500 stars have been established for years. In order to have a fair comparison of curation and software repositories, only repositories that were created after January 1, 2013 were retained, resulting in 1929 repositories. To identify curation repositories within this sample, we first identified 1384 software projects, whose programming languages were automatically detected by GitHub. For the remaining 545 repositories, we manually labeled each. The criterion used to determine if a repository was a curation repository was whether the primary content of the repository was a collection of Internet resources. As a result, we identified 49 curation repositories from the 545 repositories. As we could not verify the nature of the other 496 repositories, and since our immediate interest for this paper focusedon popular curation repositories and their comparison with software repositories, we discarded these 496 repositories from the sample. After identifying the most popular curation and software repositories, to answer RQ1, i.e., _how are curation repositories different from the typical software repositories of GitHub_, we aggregated the activity log data into 49 curation repositories and 1384 software repositories, respectively, and applied a quantitative method to compare them. Specifically, for each type of activity, we analyzed whether the number of the activities for curation projects was different from the number of activities for software repositories. To answer RQ2, i.e., _what is the emerging role of curation repositories in the GitHub community_, we performed content analysis on the 49 repositories. For each curation repository, we coded the repository name, description, curated items, pull requests, and owners' profiles, which were retrieved from GitHub on September 1, 2014. Open coding strategies as suggested by [PERSON] (1987) were applied to developing a coding scheme [17]. Themes and concepts were identified, discussed, and refined iteratively among researchers [18]. The results are presented in the following section.