Inequality of Educational Opportunities and the Role of Learning Intensity
利用德国G8改革（压缩学制但不减课程）作为准实验，发现学习强度提高加剧了教育机会不平等，因为家长资源和私人补习的作用增强，且对数学/科学的影响大于阅读。
• G8 reform in Germany compresses existing curriculum into fewer years of schooling. • Analysis relies on PISA data and applies DiD and machine learning methods. • Inequality of Educational Opportunities rises with increasing learning intensity. • Effects are stronger when measured with respect to mathematics/science than reading. • Intensified curricula make education more dependent on parents and private tutoring. Over the 2000s, many federal states in Germany shortened the duration of secondary school by one year while keeping the curriculum unchanged. The quasi-experimental variation arising from the staggered introduction of this reform allows me to identify the causal effect of increased learning intensity, the ratio of curricular content covered per year, on Inequality of Educational Opportunity (IEOp), the share in educational outcome variance explained by predetermined circumstances beyond a student’s control. Findings show that higher learning intensity aggravated IEOp due to parental resources becoming more important through support opportunities like private tuition, adapting to an intensified educational process. The effect is stronger for mathematics/science than for reading, implying the existence of subject-dependent curricular flexibilities. My findings underscore the importance of accounting for distributional consequences when evaluating reforms aimed at increasing educational efficiency and point to the role of learning intensity for explaining changes in educational opportunities influencing social mobility.