5 Execution of Reproductions
5.0.1 Gathering resources
Prerequisites for reproduction studies are available data and ideally also code. These are usually linked within the manuscript and shared via repositories (e.g., Zenodo, OSF.io, github.com, gitlab.com) or they are part of the supplemental materials that are listed on the article’s website. In special cases, an entire original manuscript may be reproducible and written in Markdown language. Researchers searching for target studies to reproduce can check topfactor.org and filter for Data transparency level 3 (https://topfactor.org/journals?factor=Data+Transparency; will no longer be updated). They can also use the extensive database of economics studies with available data compiled by Sebastian Kranz (https://ejd.econ.mathematik.uni-ulm.de/).
If data are not publicly available, researchers can contact the authors of the original study. In this case, we recommend them to adhere to Guide for Accelerating Computational Reproducibility in the Social Sciences (ACRE) guidelines for constructive communication (Berkeley Initiative for Transparency in the Social Sciences 2020).
When re-using data, researchers need to respect licenses. Generally, research data should be licensed openly, that is re-use and alteration should be permitted, likely requiring citation of the original resource (e.g., CC-BY 4.0 Attribution). Note, however, that non-derivative licenses may prohibit reproductions; in that case separate approval would be required from the copyright holder.
When it comes to reporting, Ankel-Peters et al. (Ankel-Peters et al. 2025) provide a table for reporting results from the computational reproduction that includes resource availability (e.g., raw data, cleaning code, analysis code).
5.0.3 Identification of Claims
Statistical analyses and their results are always used as a way to evaluate a certain claim. While Ankel-Peters et al. (Ankel-Peters et al. 2025) recommend reproductions to identify “results [that] are essential for the paper’s main argument to hold“, we acknowledge that a reproduction can also focus on secondary results if they are relevant in some other context. In either case, reproduction researchers need to justify the choice of the claim in their report.
5.0.4 Preregistration
Preregistrations contain a description of the planned study or analysis prior to their execution. This way, they can reduce researchers’ ‘degrees of freedom’. In the case of reproductions, they can prevent QRPs (e.g., “null hacking”, (Bryan, Yeager, and O’Brien 2019); “gotcha bias”, (Berinsky, Druckman, and Yamamoto 2021)) as long as the entire analysis plan is preregistered (Brodeur et al. 2024) and the data have not yet been accessed. While a numerical reproduction with available code does not require preregistration, we recommend a priori specification of all further planned analyses.
It should be noted that a preregistered analysis plan or analysis script is much easier to create with access to data and reproductions are impossible with unavailable data, pre-registration cannot exclude the risk of authors having already looked at the data, yet making fraudulent claims regarding data access in a pre-registration is evidently academic misconduct. How much weight readers and reviewers will give to a pre-registration based on data that could have been accessed already will differ, but generating it is a way to keep ourselves accountable and produce robust reproductions.
5.0.5 Deviations
To increase trust in the reported results, reproduction researchers need to report them in a transparent way, in a possible pre-registration and the final report. Ideally, all changes to the original procedure are explained, justified, and hypotheses about their expected effect on the outcomes are reported. Note that some journals’ publishing reproductions require adherence to special requirements such a Registered Report format (e.g., Journal of Open Psychology Data) or including a minimum of two independent reproductions (e.g., Journal of Robustness Reports).
5.0.6 Analysis
The main part of the reproduction is the analysis. Factors that are potentially relevant for reproduction success include the software of the machine that is running the code as well as versions of the software and additional packages or plug-ins. For example, users of the open source software R can get a comprehensive overview of the program version and their machine using the function sessionInfo()
, which should be included in supplementary materials. For python users, a package has been developed to run a similar function session_info.show()
(https://gitlab.com/joelostblom/session_info).
Apart from a numerical reproduction where the same code is used, reproduction researchers can explore alternative ways that should and should not affect the results, test new hypotheses or theories, and run exploratory analyses. Their report should be clearly structured to discern these methods. Finally, for statistical analyses, the reproduction report should include reproducibility indicators (Dreber and Johannesson 2024) that summarize statistical significance and relative effect sizes across the original and reproduction results. Ankel-Peters et al. (Ankel-Peters et al. 2025) recommend a visual summary of these indicators in the form of a reproducibility dashboard and specification curves (e.g., (Simonsohn, Simmons, and Nelson 2020), see also (Mazei, Hüffmeier, and Schultze 2025)). We strongly recommend reproduction researchers to consult the respective resources for further details.
5.0.7 Discussion
The discussion section should include a clear evaluation of the reproduction success on different levels (Ankel-Peters et al. 2025). Researchers should report possible reasons for failure (e.g., objective coding errors, changes in software packages) and the role of differences between the original and the reproduction studies’ results with respect to their conclusions. Finally, if the original authors provided comments, the reproduction report should include a discussion of them.