Challenges

The Leifeld Lab uses research challenges as a structured way to explore collaboration, supervision, and formal roles. Challenges are designed to be small, concrete, and consequential: they address real methodological or infrastructural problems linked to the lab’s work.

Engagement through challenges serves several purposes:

Challenges are not coursework, internships, or unpaid labour. They are entry points into ongoing research problems.

The idea behind challenges

How challenges work

A challenge typically involves:

  • a clearly defined methodological or software problem;
  • existing code, data, or papers as context;
  • an expected output (code, documentation, diagnostics, or a short technical note);
  • a limited scope, designed to be tackled independently.

There is no fixed timeline. Some challenges can be explored in days, others may take weeks. Not all attempts lead to further collaboration, and completion does not guarantee a formal position.

What matters is how you engage with the problem, not whether you “solve” it perfectly.

What challenges are used for

Sustained engagement with challenges often forms the basis for:

  • closer research collaboration;
  • co-authored methodological or applied work;
  • supervision arrangements (e.g., MSc projects, PhD co-supervision);
  • support for applications to externally funded PhD or postdoctoral positions.

What makes a strong challenge contribution

Strong contributions typically show:

  • independent problem formulation and scoping;
  • attention to inferential assumptions and edge cases;
  • clean, inspectable code or analysis;
  • clear documentation of decisions and limitations.

Prestige, degrees, or institutional affiliation matter much less than evidence of careful, sustained engagement.

How to get started

If you are interested in engaging with a challenge:

  1. Browse the lab’s software repositories and documentation.
  2. Identify a problem or open issue that aligns with your skills and interests.
  3. Get in touch briefly with a concrete proposal or question.

Unsolicited project proposals are welcome, but they should be specific and grounded in existing work.

Current open challenges

IRT scaling backends for discourse networks

Repository: dna
Focus: Analysing the design, feasibility, and validation of a Java implementation of IRT-based scaling for actors and concepts in discourse networks. The challenge centres on understanding data transformations, modelling assumptions, and estimation requirements in existing reference implementations (R and JAGS), and assessing how comparable functionality could be implemented or approximated in DNA’s Java codebase. This challenge treats IRT integration as an inferential and infrastructural design problem, not as a straightforward feature request. It is motivated by the desire to reduce external dependencies and make scaling methods directly available within DNA.
Typical outputs: Technical problem descriptions, design notes, standalone Java prototypes for MCMC estimation, replication or stress-testing of published results, or diagnostic analyses of convergence, identifiability, and estimation behaviour.
Entry point: https://github.com/leifeld-lab/dna/issues/313

Loyalty and temporal commitment in discourse networks

Repository: dna
Focus: Analysing and extending measures of actors’ loyalty (or temporal commitment) to policy concepts in discourse networks. The challenge centres on diagnosing the assumptions and limitations of existing loyalty measures that combine frequency and recency using fixed temporal discounting parameters, and exploring whether decay or commitment parameters can be estimated from data rather than fixed a priori. The emphasis is on measurement design, identifiability, and inferential interpretation in temporal bipartite networks.
Typical outputs: Technical analyses of existing loyalty measures, simulation-based diagnostics of sensitivity to decay or window parameters, alternative formulations or estimators (e.g., Bayesian or optimisation-based), prototype implementations in R or Java, or short technical notes clarifying interpretational and identifiability issues.
Entry point: https://github.com/leifeld-lab/dna/issues/314

Reporting infrastructure and Quarto integration

Repository: texreg
Focus: Diagnosing the feasibility and design of integrating Quarto support into texreg, with attention to output contracts, rendering pipelines, and the scope of reporting infrastructure. This challenge builds on prior discussions and unsuccessful partial implementations by contributors and treats Quarto integration as a design problem rather than a missing feature. The aim is to clarify what a principled integration would require, where responsibilities should lie (texreg vs Quarto or extensions), and which trade-offs or limitations are unavoidable.
Typical outputs: Design notes, architectural analysis of existing attempts, minimal prototypes, or reasoned arguments about why full integration may or may not be desirable.
Entry point: https://github.com/leifeld-lab/texreg/issues/223

Parliamentary data infrastructure for temporal networks

Repository: lobbynet
Focus: Designing and prototyping components of a reproducible pipeline for acquiring, linking, and representing parliamentary lobbying data as temporal relational networks.
Entry point: https://github.com/leifeld-lab/lobbynet/issues/1