1 Educational Inequality: Theories, Explanations, and Gaps Between Social Stratification and Comparative Political Economy
In the light of our findings, the Persistent Inequality thesis is evidently challenged, and the prevailing view that class inequalities in educational attainment will decline only under exceptional circumstances must be reconsidered. […] the focus needs to shift not only from the explanation of stability to the explanation of change, but from accounts based on the assumption of widespread commonality to those that encompass the differences between countries.
Abstract:
How and why do (or do not) educational inequalities vary across countries and over time? Different intellectual traditions offer theories and analytical frameworks with important implications for this question, yet they could have developed with a deeper engagement with one another. We trace the developments of two of these fields—social stratification and comparative political economy—arguing that a joint reading yields key analytical advantages with direct consequences for new empirical research. While the social stratification literature extensively described educational inequality across many countries from the twentieth century onwards, causal theories capable of explaining their findings once expectations of persistent inequality were proven false remained underdeveloped. This field was initially marked by historicist theories, succeeded by a consensus around the thesis that educational inequality remained invariant over most of the twentieth century. Over the last two decades, this consensus has eroded; yet part of the new research in the field remains reticent to advance and test new explanations even after the causal assumptions underlying earlier theories eroded (Jackson, 2021), while other scholars continue to reiterate the persistence thesis. Comparative political economy, on the other hand, is rich in theoretical propositions that conceive of education as a political-economy problem, yet these theories have rarely been applied to the empirical study of individual-level educational access inequalities. A synthesis of both perspectives can generate testable theoretical propositions consistent with recent empirical findings. We also discuss ways of adjudicating between theories, perspectives on causation, and the value of description in the field.
1.1 Introduction
“Suppose government leaders were to seek our advice on how to increase mobility. Based on the research, we would have nothing to say” (Beller & Hout, 2006, p. 353). The remark is Yossi Shavit’s, co-editor of a landmark volume that established the sociology of social stratification’s consensus on the durability of class inequality in education, delivered at the fiftieth-anniversary meeting of RC28, the International Sociological Association’s research committee on social stratification. How did the tradition that most systematically studied educational inequality come to have nothing to say about government actions that might reduce it? The question remains live because, two decades on, and despite substantial changes in the field, much published research still rests on theories that leave no room for the contingency Shavit’s confession points to—namely, the possibility that policies policy can affect inequality. In this text, we review theories that contribute to explaining why and how educational inequalities vary (or not) across countries and over time, focusing on the role of state action.
This question cannot be answered from within any single intellectual tradition in the social sciences; rather, several fields have developed theories from which relevant implications can be derived. Although social stratification is the field has most conducted empirical research measuring educational inequality among individuals(Brand et al., 2025), it is not the sole literature addressing the topic. Alongside it stands the comparative political economy of education—scholarship that conceives of education as a problem of political economy, in which educational access, quality, and funding are the object of political disputes and interests that centrally shape who obtains it (Ansell, 2010; Busemeyer, 2014; Garritzmann, 2016; Manzano, 2017; Paglayan, 2026)—as well as other perspectives advanced by economists, sociologists, and political scientists that do not fit neatly within either tradition, such as world society theory and human capital theory, which advance different framings (for reviews of that literature, see Carnoy, 1985, 2024; Ansell, 2010; Busemeyer & Trampusch, 2011; Garritzmann, 2026; Paglayan, 2024, 2026).
This paper reviews the theories of each tradition and their implications for the mechanisms and expectations of change in educational inequality, examining the theoretical paradigms that inform current empirical research on tertiary education policy and access inequality (Garritzmann & Seng, 2026; Gomes, 2024; Salata et al., 2025; Salata et al., 2026). The review is organized around whether and how politically contingent factors shaping state action can affect educational inequality, thereby contributing to adjudicating between competing explanations. We devote much of the text to the idea, extensively discussed in the comparative political economy debate and later incorporated into the social stratification debate, that the redistributive policies of the welfare state (designed to redistribute resources, improve living standards, and reduce inequality) are a central source of explanation for educational inequality.1
Our focus in this review, however, is on how these academic traditions theorized, in the context of the emergence of the welfare state, how it affected income inequality, maily by expanding public services and raising living standards served as crucial drivers of educational equalization (Beller & Hout, 2006; Breen et al., 2009; Breen, 2010; Erikson & Jonsson, 1996). In reviewing rational-action models of family decision-making within social stratification, it becomes evident that the field overgeneralized the Maximally Maintained Inequality (MMI) hypothesis (Raftery & Hout, 1993)—the theoretical pillar of the persistent-inequality consensus (Shavit & Blossfeld, 1993). The empirical observation that equalizing policies failed in specific historical settings was misconstrued as a general law in building the persistent inequality consensus, leading to the assumption that higher-income groups would systematically, if not always, capture new opportunities first, underemphasizing cases where they did not. A major contribution of that finding was establishing that expansion would not automatically yield equalization; consequently, MMI became a baseline assumption of how inequality would behave during periods of expansion, shared across social stratification (Raftery & Hout, 1993) and comparative political economy (Ansell, 2010).
It became increasingly clear with subsequent empirical evidence that the persistent inequality perspective should be reconsidered. Social-democratic welfare regimes and the United States standing out as notable exceptions (Hout & DiPrete, 2006, pp. 8–9). Consequently, MMI is best mobilized not as a law-like empirical regularity, but as a theoretical baseline against which empirical trends are evaluated (Hout & DiPrete, 2006). The microfoundations posited by rational-action models are consistent with diverse outcomes—including the increase, persistence, or reduction of inequality. They therefore account for how appropriately designed state policies, by targeting specific populations and successfully destratifying and decommodifying access, can produce equalizing results (Breen et al., 2009; Breen, 2010). The insight that reducing educational stratification—specifically by curtailing dead-end tracks that block access to further education—decreases inequality was consolidated in the volume by Shavit et al. (2007). The authors also reinterpreted MMI as an empirical description that can reflect an inclusive process, given that constant odds ratios in an expanding system imply growing absolute participation across all social origins. This perspective has gained ground in recent stratification research, though part of field remains reluctant to attach causal significance to state policy and develop theories and empirical tests to that expectation after documenting a systematic reduction of inequality across many countries in the second half of the twentieth century.
The review shows that influential authors in social stratification have deconstructed the consensus behind the idea that educational inequalities are persistent, arguing that improvements in living conditions and the welfare state are central factors explaining the decline in inequality (Breen et al., 2009; Breen, 2010; Breen & Müller, 2020). Yet they never synthesized that finding into an abstract theoretical framework with a clear mechanism to explain the well-documented equalization across many Western countries, formulating its components instead as speculative possibilities rather than as a new theory generating expectations about educational inequality at the same level of abstraction as MMI or the competition hypothesis. Comparative political economy, for its part, has produced many theories relevant to the topic (Garritzmann & Seng, 2026) without setting out to measure educational inequality at the individual level as systematically as stratification research has done. The two fields are, in this sense, complementary in their gaps. Bringing the two fields into dialogue can yield significant advances in the metrics and theories of educational inequality and support the advancement of the research agenda.
Using the inference to the best explanation (IBE) reasoning (Spirling & Stewart, 2025) to adjudicate between rival explanations, and drawing on the diagnosis above, we propose a framework that synthesizes these diagnoses by advancing a mechanism consistent at once with the stratification literature’s diagnosis of the end of persistent inequalities, with the microfoundations proposed by Raftery & Hout (1993), and with the comparative political economy diagnosis that politics matters and that a redistributive politics of education can account for the reduction of inequality of access to tertiary education.
That framework rests on two baseline premises that this text inherits rather than defends: first, that enrollment expansion does not automatically yield equalization (Ansell, 2010; Raftery & Hout, 1993); second, that aggregate educational expenditure cannot proxy redistribution unless explicitly targeted by income (Garritzmann, 2016; Manzano, 2017). Evaluating the distributive consequences of reform therefore requires data that directly link household income to enrollment—a requirement that shapes the analytical approach of the chapters that follow.
It rests, furthermore, on what is no news to comparative political economists but is an underemphasized perspective for much of social-stratification theory that has not yet, as a field, even thou many of it’s central authors have (Beller & Hout, 2006; Breen, 2010; Erikson & Jonsson, 1996), incorporated these advances: that educational inequality is heavily contingent on factors shaped by politics. Among them is the stratification of the educational system itself, which can systematically channel people from a given socioeconomic background into positions that limit their access to tertiary education; and the commodification of access (Busemeyer, 2014; Esping-Andersen, 1990) — that is, the dependence of access to education on income — which can be understood as a particularly important form of stratification enacted through the market rather than through formal segmentation of educational pathways. Indeed, stratification research made by Breen et al. (2009) onwards has itself converged with Esping-Andersen’s typology of welfare regimes to explain why educational equalization succeeded in social-democratic contexts like Sweden while lagging in liberal regimes like Britain (Breen, 2010).
Decommodification, in turn, is achieved through subsidies and incentives to education — whether direct policy instruments, or broader subsidies that raise people’s standard of living and reduce their dependence on market income and on the need to sell all their time to work, freeing part of that time for continued study. Some policies, such as Conditional Cash Transfers (CCTs), even make children’s school enrollment a condition of eligibility. Other policies operate through a different mechanism, one that affects people’s market income directly — that is, how much they earn through work — such as policies that raise or protect employment and regulate the earnings of the lower classes, including pension policy and the minimum wage. This could be framed as predistribution (Hacker, 2011; Oba, 2026) — that is, the institutions and policies that shape “market” income directly, before any state taxation or transfer is even accounted for.2 This can be counterintuitive for some perspectives on education, which is frequently seen as itself a vehicle of equalization. Yet education is not only no silver bullet for reducing income inequality (Medeiros et al., 2020); improvements in people’s living conditions have themselves proven to be a fundamental condition for reducing inequality of access to education. The relationship between income and education, moreover, is largely endogenous in many contexts, with economic crises and falling incomes leading to dropout from the formal education system (Witteveen, 2021).
We call this analytical lens the income barrier framework: the intuitive idea that easing people’s need to secure the income essential to daily life reduces income-based inequality in access to education, by mitigating the cost side of the cost-benefit tradeoff involved in choosing additional education. This mechanism, which we propose not as the only one but as a highly relevant one, has strong grounds for mattering considerably to income-based inequality in access to education. It displaces mechanisms cast as apolitical regularities — such as competition-based explanations (Alon, 2009) or the saturation of the wealthier classes (Shavit & Blossfeld, 1993) — and other mechanisms that abstract from the fact that educational inequality is, fundamentally, a problem of political economy (Garritzmann & Seng, 2026; Paglayan, 2026). The explanation, therefore, converges with the evidence that Breen et al. (2009) and Breen (2010) mobilize to explain equalization in Europe—where stratification scholars themselves drew on welfare-state regimes (Esping-Andersen, 1990) to account for cross-national variations—and is consistent with accounts such as Witteveen (2021)’s. Yet our framework recasts the question explicitly as a problem of political economy, brings it into systematic dialogue with comparative political economy, and packages it as an abstract mechanism capable of explaining other settings as well.
Redistribution is not the only motivation behind educational expansion capable of reducing access inequality. Especially at compulsory levels, state-building, political control, diffusion, transmission of values, and economic development agendas also drive expansion (Ansell, 2010; Kang et al., 2024; Paglayan, 2026). Most contries expanded primary education with precisely those aims in mind, not equalization or redistribution, but they had the effect of reducing the socioeconomic bias in access to educatio since states may massify and event universalize access in pursuit of political control over their populations (Paglayan, 2024). With democratization, however, education increasingly came to be analyzed as a welfare policy capable of enhancing social fluidity, provided access is less unequally distributed (Beller & Hout, 2006; Busemeyer, 2014; Corak, 2013). At the tertiary level, redistributive, skill-formation, and mobility dimensions predominate (Garritzmann & Seng, 2026), which does not mean that other political effects, such as the transmission of values, should not be investigated in other research.↩︎
For more on predistribution, see Oba (2026) and Hacker et al. (2013). For empirical work related to the concept, see Lupu & Pontusson (2023), specially Cavaillé (2023).↩︎