Mario Martinez-Jimenez

I will be on the academic job market this year (2026-27). 

I am an Imperial Research Fellow in the Department of Economics & Public Policy at Imperial Business School. I was a Visiting Postdoctoral Scholar at Stanford University in the Department of Health Policy, Stanford School of Medicine for the 2025–2026 academic year.

Research fields: health, labor, and child development.

I am a health and labor economist. I study how health and labor-market shocks shape family decisions and economic well-being over the life course. My work focuses on early-life health, mental health, and fertility, with a broader interest in how disadvantage is transmitted across generations.

Referees:

Job Market Paper

When Careers Stall: Early-Career Job Insecurity and Fertility over the Life Cycle

with Judit Vall Castello

Abstract

Can greater exposure to job insecurity at labor-market entry have lasting effects on fertility? We study Spain’s 1984 reform, which sharply expanded fixed-term hiring for new entrants while preserving protection for permanent workers. Using differences in reform exposure across nearby birth cohorts of low- and high-skilled women, we find that the reform increased years of non-permanent employment and lowered contribution-based income among low-skilled women, without a detectable change in days worked. Exposed low-skilled cohorts experienced a 15.2% decline in births per woman at the cohort level and delayed first motherhood by about five months. Mechanism evidence suggests that employment insecurity constrains the realization of fertility plans, with exposed low-skilled women more likely to have fewer children than they desire. We build and estimate a life-cycle model linking early-career employment risk to fertility decisions over the reproductive horizon. The model attributes the fertility decline primarily to adverse entry conditions and accumulated employment insecurity, rather than lower early-career resources or the mechanical consequences of later childbearing, and shows that reducing insecurity can recover some forgone fertility. Together, the evidence shows that reforms increasing early-career job insecurity can delay motherhood and reduce realized fertility.

🏆 Award

Winner of the International Health Economics Association (iHEA) Early Career Researcher Best Paper Award.

🎤 Presentations

NBER Conference on Fertility and Declining Population Growth in High-Income Countries, Stanford University, ASHEcon, EALE, and IHEA.

Working Papers

How do economic shocks impact upon the effect of retirement on mental health?

with Bruce Hollingsworth and Eugenio Zucchelli (Submitted)

Abstract

Economic crises are common, but their timing is uncertain. This paper examines whether the mental health and well-being effects of retirement change in the presence of major economic shocks. Using a range of causal empirical methodologies, with a particular focus on a fixed-effects instrumental variables approach, we analyse longitudinal data from the English Longitudinal Study of Ageing (ELSA) covering a representative sample of over 50-year-old individuals in England. We exploit regional variations in unemployment rates following the economic crisis in the short term (2004-2013) and the longer term (2004-2019). The findings show that moving into retirement while living in a region and year particularly hit by the crisis significantly decreases the probability of reporting a new depression or anxiety diagnosis by 4.9 percentage points, mostly driven by white-collar and men retirees. We show that financial security, healthy lifestyles, and the ability to early retirement help maintain the mental health benefits of retirement during economic crises. These findings suggest that policies enhancing financial security and resilience and promoting healthy lifestyle initiatives could bolster retirees' resilience and support healthy ageing.

🎤 Presentations

Presented at: EALE, HESG, LoLaHESG, PHE Public Health Research and Science Conference, and Health Economics at Lancaster seminars.

The Role of Early Life Conditions on the Development of Child's Adaptive Behaviour Skills

with Edith Aguirre (R&R at the European Journal of Health Economics)

Abstract

This paper examines how early-life factors, including perinatal and neonatal conditions, shape children's communicative, physical, and socio-emotional skills by age three in the United Kingdom. These three domains are measured by adaptive behavior scales, widely used in the UK to assess early developmental delays and support clinical diagnosis. Using data on 4,335 children from the Understanding Society: Pregnancy and Early Childhood (PEACH) dataset between 2011 and 2023, we study how infant health at birth and breastfeeding are associated with the development of adaptive behavior skills at age 3. We rely on selection on observables models, including rich-controlled OLS, propensity score matching, and correlated random-effects models, drawing on detailed child, maternal, and household covariates measured from birth through age three. We find that poorer perinatal health is associated with slower physical development, whereas breastfeeding is linked to enhanced communication and socio-emotional development. Heterogeneity analyses indicate more pronounced perinatal-health effects for boys and non-firstborn children. We further implement a parametric mediation analysis and show that maternal engagement explains around 15% of the total benefits of breastfeeding for adaptive behavior, but does not positively mediate the relationship between adverse perinatal health and skill development. Our findings underscore the importance of public health policies that target support for children born in poorer perinatal health, helping to reduce early-life inequalities and promote more equitable child development.

🎤 Presentations

Presented at: ASHEcon, IHEA, II Rome Health Economic Workshop, and the School of Public Health at Imperial College London.

Work in Progress

Who Gets the Shot? Determinants of Childhood Vaccination among Medicaid Beneficiaries.

with Petra Persson (Stanford University), Maya Rossin-Slater (Stanford University) & Grace Sventek (Stanford University).

Abstract

Abstract forthcoming.

When Care Is Far from Home: Access to Neonatal Care and Maternal Mental Health.

with Genna Campain (Stanford University), Helen Kissel (Simon Fraser University) & Maya Rossin-Slater (Stanford University).

Abstract

Abstract forthcoming.

After the Gunfire: Local School-Shooting Exposure and Youth Mental-Health Care in U.S. Primary Care.

with Chris Lowenstein (University of Missouri) & David Rehkopf (Stanford University).

Abstract

How far does the health-system burden of community violence extend beyond people who are physically injured? We study school shootings as sudden local shocks, linking 2021–2024 American Family Cohort primary-care records to 28 shootings in which at least one person was killed or wounded. A stacked event study compares children living 0–5 miles from the affected school with children living 10–15 miles away. Following a shooting, nearby children were 3.96 percentage points more likely to have a quarter with recorded mental-health or neurodevelopmental care, an increase equal to 37% of the pre-shooting comparison-group mean. The response appears in diagnoses, procedures, and clinical notes concerning suicidal ideation or ADHD, but we do not detect comparably clear changes in medication use or overall primary-care contact. This composition is consistent with trauma entering routine care partly through clinical recognition, assessment, and follow-up rather than prescriptions or additional contact alone. Estimates remain positive when any shooting is omitted, although they are smaller under equal-event weighting and alternative comparison rings. These findings show that casualty counts and prescription records can miss a diffuse outpatient response to local violence and that post-event planning should extend beyond direct victims and the affected school.

Do Climate Mobilisations Weaken Young Adults’ Economic Attachment? Evidence from Fridays for Future.

with Laure de Preux (Imperial Business School).

Abstract

Do nearby climate mobilisations weaken young adults' attachment to work and education? We link European Social Survey interviews to the timing and location of five Fridays for Future mobilisations from 2019 to 2023. Our triple-difference design compares four-week near-versus-far changes for adults aged 18–40 with the same changes for adults aged 41–50. The events sharply increased movement-specific search attention. Yet nearby mobilisation did not reduce an index of education, employment, job search, and financial security: the estimate is 0.26 standard deviations (95 percent confidence interval [−0.09, 0.62]). Outcome-specific bounds exclude a 20 percent deterioration in education, active unemployment, and income difficulty, but not in paid work or NEET status. The well-being estimate is negative but imprecise (−0.23 standard deviations; [−0.55, 0.09]) and varies across younger age bins, so it does not support a common youth welfare effect. These estimates capture an age-differential response to regional proximity, not the effect of attending a protest or personally noticing it. The evidence rejects broad short-run economic withdrawal while leaving temporary affective costs unresolved.

Fragile Beginnings: Neonatal Health Risk and Educational Achievements.

with Orla Doyle (University College Dublin).

Abstract

Neonatal units care for clinically vulnerable newborns, including infants born premature or at low birthweight. Yet little is known about whether neonatal attendance signals later educational needs. We use data on 8,406 nine-year-olds from Growing Up in Ireland to study reading tests and parent- and teacher-reported difficulties. After adjusting for observed birth and family characteristics and applying the survey weight, children with a history of neonatal care scored about 0.05 standard deviations lower on two reading measures. Neither reading estimate was statistically different from zero, although the confidence intervals also allowed modest disadvantages. Parents reported a 2.8-percentage-point higher rate of learning difficulties; this estimate was also not statistically different from zero, while teachers reported no difference. Caregiver-reported dyspraxia was more common in one follow-up analysis, but direct tests and teacher reports did not show a similar pattern. Adjustments for missing outcomes and plausible reporting error did not change the main interpretation. Neonatal attendance overlapped with, but was not equivalent to, low birthweight or prematurity. The low-birthweight analysis revealed an important design constraint: nearly four in five low-birthweight children attended neonatal care, so the cohort cannot support a separate attendance comparison within this high-risk group. Overall, the findings support using neonatal attendance as a practical early-life marker to help identify children who may benefit from sustained developmental and educational follow-up. The study therefore shows that neonatal attendance can complement birthweight and prematurity when targeting follow-up, while the effects of admission and treatment require designs with stronger clinical data and exogenous variation.

Schooling and Gender Norms.

Solo-authored.

Abstract

Does schooling make people judge women's and men's employment more equally? This paper combines seven rounds of the European Social Survey with country- and cohort-specific compulsory-schooling reforms and a randomized split-ballot vignette. One additional year of schooling raises rejection of men's priority for scarce jobs by 1.6 percentage points and a two-item employment-equality index by 1.2 points. The job-priority estimate remains significant under country-level wild-bootstrap inference, and every round-specific employment coefficient is positive. Independently, assigning an otherwise identical full-time-work scenario to a mother rather than a father lowers approval by 18.5 percentage points, with penalties of 22.9 points in 2006 and 14.4 points in 2018. The instrumental-variables estimate of schooling's moderation of this penalty is 0.9 percentage points per year (standard error 0.7), so the data do not establish that schooling closes the gap. Schooling promotes more equal stated employment attitudes, while a large maternal-employment penalty remains and is not shown to narrow with education.

Publications

first/lead author    senior author

Economics

Health Policy / Health Services Research