Research

Publications

1. Socioeconomic status and enrolment in science and maths: a machine-learning approach

   Dáire Crotty and Ciarán Murphy

   Education Economics, 2026

   DOI Bib

   @article{crotty2026stem,
     title = {Socioeconomic status and enrolment in science and maths: a machine-learning approach},
     author = {Crotty, Dáire and Murphy, Ciarán},
     journal = {Education Economics},
     year = {2026},
     pages = {1--28},
     doi = {10.1080/09645292.2026.2688823},
     url = {https://doi.org/10.1080/09645292.2026.2688823}
   }

Working Papers

1. Building Success: The Effect of On-Campus Housing Expansions on Student Outcomes

   Ciarán Murphy

   2026

   Abs PDF

   Housing shortages are increasingly cited as barriers to degree completion. Using a 17-year panel of 1,208 U.S. colleges, I estimate the effect of dormitory expansions on retention and graduation via within-college differencing models, confirmed by stacked difference-in-differences. Large expansions do not affect first-year retention but raise four-year graduation by 1–2.3 percentage points; effects grow with expansion size and cohort exposure and reflect higher total completion rather than re-timing. Mechanism analyses find no rent-market spillovers, pointing to campus housing access as the primary channel. Expanding on-campus capacity is a tractable, institution-controlled policy to raise graduation rates.

2. The Origins of the STEM Gender Gap: Evidence from an Analysis of Secondary School Subject Selection

   Dáire Crotty and Ciarán Murphy

   2025

   Abs PDF

   Secondary school subject choices are a key gateway to STEM (Science, Technology, Engineering and Maths), yet their determinants remain underexplored. Using the Growing Up in Ireland study, this paper employs regression and decomposition analysis to examine STEM participation. We document substantial gender gaps in practical-based STEM subjects, but not in science or maths. Lower secondary choices play a central role in shaping later trajectories and explain most upper secondary gender gaps. However, lower-secondary gaps are not explained by conventional mechanisms such as early characteristics, comparative advantage, schools, or peers. Results are robust to alternative specifications, including machine learning methods.

3. Lockdowns and Conspiracy Theories: Evidence from European Policy Variation

   Ciarán Murphy

   2026

   Abs PDF

   When European governments locked down their populations during Covid-19, they inadvertently increased demand for conspiracy theories. This paper provides demand-side evidence on what drives online conspiracy narratives, exploiting differential variation in lockdown stringency across 31 European countries. Stricter lockdowns significantly raised conspiracy search interest during 2020–2021. Evidence points to social isolation as the operative mechanism: the sustained level of restriction predicts conspiracy search while week-on-week changes do not, and restrictions that physically confine people drive the result while mask mandates do not. The findings suggest that social capital disruption is a distinct driver of conspiratorial information-seeking.

Work in Progress

1. The Other Side of the Game: Coaching Allocation and Player Effort in Football Academies

   Ciarán Murphy

   2025

   Work in progress – draft available soon

   Abs

   Professional soccer academies admit cohorts of players annually with the aim of maximising the playing ability of the select few who are ultimately offered professional contracts. The academies allocate coaching between players with this aim, while players choose the level of effort to exert in academy training. For the unsuccessful players, this effort is sunk and can come at the cost of fully focusing on an education or a conventional career. This paper shows that the coaching allocation which maximises the expected ability of the successful players also maximises the expected wasted effort of the unsuccessful players, demonstrating an externality which exists within this system.

Reports

1. Exploring the Gender Pay Gap in Early Adulthood: A Longitudinal Analysis Using Growing Up in Ireland Data

   Dáire Crotty and Ciarán Murphy

   2026

   Commissioned research report for the Department of Children, Disability and Equality

   Website