  Self-admitted technical debt (SATD) refers to technical debt that is
intentionally introduced by developers and explicitly documented in code
comments or other software artifacts (e.g., issue reports) to annotate
sub-optimal decisions made by developers in the software development process.
  In this work, we take the first look at the existence and characteristics of
duplicate and near-duplicate SATD comments in five popular Apache OSS projects,
i.e., JSPWiki, Helix, Jackrabbit, Archiva, and SystemML. We design a method to
automatically identify groups of duplicate and near-duplicate SATD comments and
track their evolution in the software system by mining the commit history of a
software project. Leveraging the proposed method, we identified 3,520 duplicate
and near-duplicate SATD comments from the target projects, which belong to
1,141 groups. We manually analyze the content and context of a sample of 1,505
SATD comments (by sampling 100 groups for each project) and identify if they
annotate the same root cause. We also investigate whether duplicate SATD
comments exist in code clones, whether they co-exist in the same file, and
whether they are introduced and removed simultaneously. Our preliminary study
reveals several surprising findings that would shed light on future studies
aiming to improve the management of duplicate SATD comments. For instance, only
48.5% duplicate SATD comment groups with the same root cause exist in regular
code clones, and only 33.9% of the duplicate SATD comment pairs are introduced
in the same commit.
