Training Materials, Resources, and Data Tools

IPR fellows work with graduate students and research staff to develop software programs and other data tools that are made available to the public. Please check back periodically for updates and new developments.

Balancing 2020 Census Cost and Accuracy

Consequences for Congressional Apportionment and Fund Allocations. In an IPR working paper, former IPR graduate research assistant Zachary Seeskin, now a statistician at the University of Chicago, and IPR statistician Bruce Spencer examine the effects of alternative error profiles for the 2020 census on apportionment of the House of Representatives and on allocations of federal funds. The paper describes the methods of analysis and the findings. The software and data used to generate the analyses are available here.

Occupational Licensing

Over the past few decades, occupational licensure quietly became the norm for a broad swath of U.S. occupations. Where only a small set of “traditional” professions once determined entry through regulation, today the practice governs a much wider range of occupations, from doctors to engineers, carpet layers to massage therapists, agricultural inspectors to wilderness guides, and fortune tellers to legal document assistants. The most substantial growth has been in blue-collar occupations, and particularly the production and transportation sector, which more than doubled its licensed workforce over the past 30 years. As of 2017, over 33 percent of workers were required to hold a license to work in their chosen occupation. The dramatic increase in licensure is comparable, in scale and possibly consequences, to other contemporaneous trends, such as deunionization, the decline of the manufacturing sector, and the rise of the college wage premium.

 To learn more about this work by IPR sociologist Beth Redbird, click here

Robust Variance Estimation (RVE) in Meta-Analysis

IPR statistician and education policy researcher Larry Hedges and IPR statistician Elizabeth Tipton, a former IPR graduate research assistant, are currently developing software for robust variance estimation. 


  • 1. Stata Macro: In Stata, type “ssc install robumeta” and the macro will install. Please see the documents below for information on the different models.
  • 2. R package: We are currently working on an R package. If you are interested in an early version of this, please e-mail Elizabeth directly.


Hedges, L. V., E. Tipton, and M. C. Johnson. 2010. Robust variance estimation in meta-regression with dependent effect size estimates. Research Synthesis Methods 1(1): 39-65. Find the erratum here.


"Bringing Evidence-Based Decision Making to New Heights," Joint Colloquium of the Cochrane & Campbell Collaborations, Keystone, Colo., October 18-22, 2010

For more information, please contact Larry Hedges or Elizabeth Tipton.