Reproducible Research

In most scientific fields, results are validated through replication: that means that different scientists run the same experiment independently in different samples and find similar conclusions. That standard is not always feasible in development research. More often than not, the phenomena we analyze cannot be artificially re-created. Even in the case of field experiments, different populations can respond differently to a treatment, and the costs involved are high.

Even in such cases, however, we should till require reproducibility: this means that different researchers, when running the same analysis in the same data should find the same results. That may seem obvious, but unfortunately is not as widely observed as we would like. The bottom line of research reproducibility is that the path used to get to your results are as much a research output as the results themselves, making the research process fully transparent. This means that not only the final findings should be made available by researchers, but data, codes and documentation are also of great relevance to the public.

Code replication

Replicating results is the most important part of reproducible research. The easiest way to guarantee that results can be replicated is to have a code that runs all data work and can be run by anyone who has access to it. Different researchers running the same code on the same data should get the same results. So to guarantee that research is transparent and reproducible, codes and data should be shared.

It is possible for the same data and code to create different results if the right measures are not taken. In Stata, for example, setting the seed and version is essential to replicable sampling and randomization. Sorting observations is also frequently necessary. Having a master do-file greatly improves the replicability of results since it's possible to standardize setting and run do-files in a pre-specified order from it. If different languages or software are used in the same project, a shell script can be used for the same purpose.

Another important part of replicable code is that it should be understandable. That is, if someone else runs your code and replicates all the results, but doesn't understand what was being done, then your research is still not transparent. Commenting code to make it clear where and why decisions were made is a crucial part of making your work transparent. For example, if observations are dropped of values are changed, the code should be commented to explain why that was done.

Software for Code Replication

Git is a free version-control software. Files are stored in Git Repositories, most commonly on GitHub. They allow the user to track changes to the code and create messages explaining why the changes were made, which improves documentation. Sharing Git repositories is a way to make code publicly available, and allow other researchers to read and replicate your code.

To learn GitHub, there is an introductory training available through GitHub Services, and multiple tutorials available through GitHub Guides

Dynamic documents

• R-markdown is a widely adopted tool for creating fully reproducible documents. It allows users to write text and code simultaneously, running analyses in different programming languages and printing results in the final document along with the text. Stata 15 also allows users to create dynamic documents using dyndoc.

• Jupyter Notebook is used to create and share code in different programming languages, including Python, R, Julia, and Scala. It can also create dynamic documents in HTML, LaTeX and other formats.

• LaTeX is another widely used tool in the scientific community. It is a type-setting system that allows users to reference code outputs such as tables and graphs so that they can be easily updated in a text document. Overleaf is a web based platform for collaboration in TeX documents.

• Open science framework is a web based project management platform that combines registration, data storage (through Dropbox, Box, Google Drive and other platforms), code version control (through GitHub) and document composition (through Overleaf).

Additional Resources

From Data Colada:

• 8 tips to make open research more findable and understandable

From the Abul Latif Jameel Poverty Action Lab (JPAL)

• Transparency and Reproducibility

From Innovations for Policy Action (IPA)

• Reproducible Research: Best Practices for Data and Code Management
• Guidelines for data publication
• Randomized Control Trials in the Social Science Dataverse

Center for Open Science

• Transparency and Openness Guidelines, summarized in a 1-Page Handout

Berkeley Initiative for Transparency in the Social Sciences

• Manual of Best Practices in Transparent Social Science Research

Reproducible Research in R

• Johns Hopkins' Online Course on Reproducible Research

Reproducible Research in Stata

• Incorporating Stata into reproducible documents