rOpenGov/retroharmonize: Improved documentation

0.2.0: Improved documentation and more consistent parameters. Reading STATA files.

The aim of retroharmonize is to provide tools for reproducible retrospective (ex-post) harmonization of datasets that contain variables measuring the same concepts but coded in different ways. Ex-post data harmonization enables better use of existing data and creates new research opportunities. For example, harmonizing data from different countries enables cross-national comparisons, while merging data from different time points makes it possible to track changes over time.

Retrospective data harmonization is associated with challenges including conceptual issues with establishing equivalence and comparability, practical complications of having to standardize the naming and coding of variables, technical difficulties with merging data stored in different formats, and the need to document a large number of data transformations. The retroharmonize package assists with the latter three components, freeing up the capacity of researchers to focus on the first.