Said Hassan
Postdoctoral Prize Research Fellow
Nuffield College, University of Oxford
I am a sociologist working at the intersection of social stratification, education, and racial and ethnic inequality. My research is driven by two broad questions. First, what can schools and educational reforms do — and, crucially, what can they not do — to reduce inequality? Second, how do educational institutions shape minority individuals’ incorporation, outcomes, and relations with majority populations?
I approach these questions through formal theory development and causal inference methods, often leveraging natural experiments and large-scale data, including full-population administrative registers.
I earned my PhD in Sociology at Nuffield College, University of Oxford, in 2024. My dissertation was awarded the Best PhD Thesis Prize by the European Consortium for Sociological Research.
Research
“Ethnic Institutions and Minority Achievement’’
Sole-authored · American Journal of Sociology (second-round revise & resubmit)
Do ethnic institutions foster or hinder minority incorporation? In this paper, I leverage a natural experiment that abruptly transferred students from Muslim schools to mainstream public schools in Denmark to answer this question.
Full abstract
Do minority-serving institutions improve or impede ethnic minorities’ social outcomes? In this paper, I examine the impact of Muslim schools in Denmark on minority students’ academic performance as a case study of this broader question. To facilitate causal estimates, I leverage a natural experiment induced by the 2016 coup attempt in Turkey, which triggered a sudden and unanticipated transfer of more than 500 students from Muslim to public schools. I find that attending a Muslim school increases academic achievement by approximately 0.30 standard deviations in reading and mathematics — an effect comparable to a full year of learning and large enough to substantially reduce the native-minority achievement gap. In a series of analyses, I show that these results are not driven by disruption associated with school transitions. To examine underlying mechanisms, I consider the roles of ethnic similarity and teacher bias and discrimination. I show that students perform substantially better in environments with higher shares of coethnic peers, pointing to ethnic similarity and culturally aligned school contexts as key drivers. Finally, I show that these gains persist into upper secondary education, with no evidence of increased reliance on social benefits in young adulthood. Taken together, the findings suggest that minority-serving institutions can promote academic success without undermining observable dimensions of social integration.Publications
Hassan, Said. 2026. “Teacher Sorting and Inequalities in Student Achievement: Unequal Exposures and Differential Returns to Teacher Qualifications.” Sociological Science. [Link] [Code]
Abstract
Teachers play a formative role in shaping children’s school experiences and ultimately, their educational outcomes. In this study, I use full population Danish administrative data to explore the consequences of unequal access to qualified teachers in three steps. First, I document strong patterns of teacher–student sorting in Denmark, one of the world’s most equal societies and generous welfare states. In short, teachers from higher socioeconomic backgrounds and with higher prior academic achievements tend to select into schools serving high-achieving children from privileged backgrounds. Second, I investigate the effect of exposure to teachers with different qualifications on students’ test score performance. To facilitate causal estimates, I exploit plausibly exogenous shocks to teacher changes induced by parental leave spells, which, I show, are unrelated to an extensive set of observed classroom characteristics, including student well-being and measures of classroom climate. Third, I explore differentials in the impact of teacher qualifications by students’ socioeconomic background. I find no consistent evidence of differential teacher effects, implying that teacher-induced learning inequalities are mainly driven by unequal exposure to highly qualified teachers, rather than unequal returns to qualifications. This suggests that policies equalizing access to qualified teachers may reduce learning disparities.
Hassan, Said, Camilla Hvidtfeldt, Lars H. Andersen, and Rebecca O. Udsen. 2023. “Do Refugee Children Impair the Academic Performance of Native Children in the School? Informative Null Results from Danish Register Data.” European Sociological Review 39(3): 352–365. [Link]
Abstract
Discussions concerning the social impact of accepting refugee immigrants arise each time large numbers of refugees apply for protection in rich countries. However, little evidence exists on how the integration of refugees into core welfare institutions affects native citizens who depend on and interact with these institutions. In this paper, we focus on whether receiving refugees in a school cohort affects the academic performance of natives, using administrative data from Denmark, which contain test scores on all children in public schools. We exploit variation in the timing of refugees’ entrance to schools to facilitate causal estimates. Our findings show that refugees tend to cluster in schools that had poorer performance even prior to the refugees’ arrival. When we take this selection pattern into account, the effect of receiving refugees on the academic performance trajectory of natives is both statistically insignificant and substantially unimportant.Best Article of the Year Prize, ECSR, 2024
Hassan, Said, David S. Kirk, and Lars H. Andersen. 2022. “The Importance of Living Arrangements for Criminal Persistence and Desistance: A Novel Test of Exposure to Convicted Family Members.” Journal of Developmental and Life-Course Criminology 8: 571–596. [Link]
Abstract
Leveraging the richness of population register data in Denmark, this study provides an in-depth examination of the residential situations of the formerly incarcerated over the first 3 years after prison. These data allow us to examine precisely who former prisoners reside with after release, and whether the characteristics of housemates, such as prior conviction status, and relationship type, such as familial ties, are associated with criminal reconviction. While Denmark has one of the lowest incarceration rates in the world, like many other Western countries, it is challenged by high recidivism rates among the formerly incarcerated. Using data on the population of all individuals released from prison between 1991 and 2014 and estimation via Cox proportional hazards models, we find that formerly incarcerated individuals who move into a residence with other individuals with criminal records have significantly greater hazards of reconviction, even after controlling for an extensive set of observed confounders. Residing with family members, particularly spouses, significantly reduces the likelihood of recidivism, but only if the family members do not have a recent criminal conviction. Results underscore the importance of housing arrangements and family ties during the post-release period.Working papers
Hassan, Said and Richard Breen. “Schools and Learning Inequality: A Theoretical Model of Quantitative and Qualitative School Effects.”
Abstract
Do schools reduce or amplify learning gaps by socioeconomic background? We contribute to this longstanding debate in three ways. First, we develop a formal model of skill formation that clarifies the estimands implicit in existing research by distinguishing between quantitative school effects—the amount of schooling children receive—and qualitative school effects—the quality of the schools they attend. Second, our model synthesizes previously contradictory findings: increasing exposure equalizes learning only if disadvantaged children have higher returns to schooling, whereas improving quality equalizes learning whenever disadvantaged children attend schools of lower quality. Third, we test the model using Danish register data and unanticipated changes in school district boundaries. We find that the returns to school quality are substantially larger than the returns to exposure, that they are concentrated among children from lower socioeconomic backgrounds, and that they are larger where socioeconomic sorting across schools is stronger. Equalizing school quality can therefore be an effective means of reducing learning inequalities.
Hassan, Said. “Parental Incarceration and Children’s Educational Outcomes.”
Abstract
How does parental incarceration affect children’s educational outcomes? I provide causal evidence on this question by combining full population register data containing detailed information on 16 Danish birth cohorts (N = 890,159) with a sibling fixed effects approach to identification. This strategy overcomes selection issues arising from unobserved family characteristics. On average, children who experience parental incarceration are 4 percentage points less likely to complete a high school degree by age 20, compared to their siblings who do not. These effects are largely concentrated among girls who experience substantially stronger detrimental effects of parental incarceration, compared to boys.Gene Carte Award (2nd Place), American Society of Criminology, 2022
Hermansen, Are S., Carina Mood, and Said Hassan. “Daughters Ahead, Sons Behind? Economic Mobility and Educational Choices among Children of Immigrants in Scandinavia.”
Abstract
Can education equalize intergenerational economic mobility for the sons and daughters of immigrants? We examine this question using population-wide administrative data on cohorts born in the 1970s and 1980s in Denmark, Norway, and Sweden. These Scandinavian welfare-state contexts constitute revealing cases because they combine open educational systems and high rates of social mobility with considerable immigration from low-income countries, alongside an increasing female advantage in educational attainment and rising concern about labor market disadvantage among less-educated men. We show that children of immigrants experience substantial upward earnings mobility relative to their parents, sharply reducing their overrepresentation at the bottom of the distribution. Conditional on parental earnings, they attain broadly similar earnings as native-origin peers from comparable family backgrounds. However, this convergence is strongly gendered, as daughters of immigrants often equal or exceed the mobility outcomes of native-origin women, whereas sons of immigrants lag behind comparable native-origin men. These differences are closely linked to educational attainment and field-of-study sorting. The findings show that education is central to immigrant mobility across generations, but its equalizing potential is primarily realized among women. Gendered educational trajectories produce gendered patterns of economic mobility, with broader implications for the intergenerational transmission of disadvantage among immigrant minorities.
Hassan, Said and Sara Geven. “Social Class in the Classroom: Teacher–Student Socioeconomic Matching and Achievement.”
Abstract
A substantial literature examines whether students benefit from being taught by teachers who share their gender or race, but little is known about socioeconomic matching, despite cultural capital theory’s emphasis on social class as the basis for the cultural alignment between students and educational gatekeepers. We ask whether students’ test performance depends on the socioeconomic match between them and their teachers. Using Danish administrative registers linking the full population of public-school students to their teachers by subject, year, and classroom (2013–2019), we triangulate across multiple sources of within-student variation—across subjects within a school year and across years within a subject—to address teacher-student sorting. Our findings show that exposure to low-SES teachers is associated with higher reading scores among low-SES students, with a similar but weaker pattern in mathematics, while high-SES students appear unaffected by their teachers’ socioeconomic background. The findings reposition teachers as active mediators in the reproduction of educational inequality.
Gensowski, Miriam and Said Hassan. “Multidimensional Teacher Value-Added: Characterizing the Good Teacher.”