  Due to the voluntary nature of open source software, it can be hard to find a
developer to work on a particular task. For example, some issue reports may be
too cumbersome and unexciting for someone to volunteer to do them, yet these
issue reports may be of high priority to the success of a project. To provide
an incentive for implementing such issue reports, one can propose a monetary
reward, i.e., a bounty, to the developer who completes that particular task. In
this paper, we study bounties in open source projects on GitHub to better
understand how bounties can be leveraged to evolve such projects in terms of
addressing issue reports. We investigated 5,445 bounties for GitHub projects.
These bounties were proposed through the Bountysource platform with a total
bounty value of $406,425. We find that 1) in general, the timing of proposing
bounties and the bounty-usage frequency are the most important factors that
impact the likelihood of an issue being addressed. More specifically, issue
reports are more likely to be addressed if they are for projects in which
bounties are used more frequently and if they are proposed earlier. 2) The
bounty value that an issue report has is the most important factor that impacts
the issue-addressing likelihood in the projects in which no bounties were used
before. Backers in such projects proposed higher bounty values to get issues
addressed. 3) There is a risk of wasting money for backers who invest money on
long-standing issue reports.

Software Engineering