Questions & explanations
1. What are selection on observables and selection on unobservables in school effects?
When studying how schools affect student outcomes, researchers must account for the fact that students are not randomly assigned to schools. Selection on observables means that students choose schools based on factors we can measure, like family income or prior grades. Selection on unobservables means they choose based on factors we cannot measure, like motivation or parental involvement. If we only control for observables, our estimates of school effects may be biased by unobservable differences. For example, more motivated students may attend better schools, making the school look effective even if it just has better students. Proper methods, like experiments or instrumental variables, try to handle both types of selection.
2. Compare methods that address observable vs unobservable selection in school effects.
Methods for observable selection are straightforward: include controls like student demographics, prior scores, and family background in a regression. This assumes that all important differences are measured. For unobservable selection, researchers need stronger methods. They might use a lottery or admission cutoff to create random assignment (like charter school lotteries). Another method is value-added modeling, which compares a student's progress to their own past performance, removing fixed unobservables. Fixed-effects models also control for unobserved school or student time-invariant factors. Each method has assumptions; no perfect solution exists. Combining multiple methods gives more confidence.
3. How does tracking affect learning outcomes in low-income settings?
In low-income settings, tracking often harms the lowest-ability students because they get placed in weak tracks with less experienced teachers and lower expectations. These students fall further behind. Meanwhile, high-ability students in top tracks may benefit from faster pacing and better peers. Overall, tracking can increase the average achievement of top students but reduce it for bottom students. In developing countries, where resources are already scarce, tracking can worsen inequality. Some studies find that tracking does not raise overall learning and may just sort students without improving total outcomes. The effect depends on how well teachers adapt instruction to each track.
4. What is a major weakness of Nozick's entitlement theory?
A major weakness is that it is very hard to know if past acquisitions were just. Most current property comes from historical events like conquest, slavery, or fraud, which violate Nozick's principles. Nozick admits that we need a principle of rectification, but it is nearly impossible to correct all past injustices. For example, how do you compensate the descendants of people whose land was taken centuries ago? Without rectification, current distributions may be unjust. Also, critics argue that Nozick's condition of 'leaving enough and as good' is unrealistic because natural resources are limited. Thus, the theory may not provide practical guidance for real-world inequality.
5. Compare the approach of No Child Left Behind and Race to the Top in holding schools accountable.
No Child Left Behind used a top-down approach: the federal government required states to set yearly progress goals and threatened penalties for missing them. It relied heavily on standardized tests. Race to the Top offered competitive grants to states that adopted certain reforms, like adopting common standards, using data to improve instruction, and evaluating teachers partly based on test scores. So Race to the Top used incentives rather than mandates. Both focused on accountability, but Race to the Top gave more flexibility and encouraged states to innovate. However, both drew criticism for overemphasizing testing and for not addressing deeper educational inequalities.
6. What is a common criticism of Rawls's difference principle?
Some critics say the difference principle is too focused on material goods and ignores other aspects of justice, such as merit or individual effort. They argue that it might reward laziness if the worst-off are those who do not work hard. Others claim it is unclear how to measure 'benefit' for the worst-off. Does it mean income, happiness, or opportunities? Also, the principle assumes that people in the original position would be risk-averse, but they might not be. Libertarians like Nozick argue that the difference principle violates property rights by forcing the rich to help the poor. Finally, implementing the principle may require a large government, which some oppose.
7. Why might cognitive skills matter more for economic growth than years of schooling?
Years of schooling only count time in class, but if students learn little, extra years add little to productivity. Cognitive skills, measured by test scores, show what people actually know and can do. A workforce with high cognitive skills can adopt new technologies, innovate, and work more efficiently. For example, a country where many students finish high school but score low on math tests may not grow fast. In contrast, a country where students master skills even with fewer school years can boost growth. Research finds that test scores strongly predict GDP growth, while years of schooling alone have weaker effects. So quality of learning matters more than quantity.
8. How can countries improve cognitive skills to boost growth?
Countries can improve cognitive skills by investing in teacher training, providing better learning materials, and ensuring all children complete primary school with solid foundations. Early childhood programs that stimulate cognitive development are very effective. Also, reducing class size and using technology for personalized learning can help. Accountability systems that test students and give feedback to schools can raise achievement. However, reforms must be context-specific: what works in Finland may not work in India. The key is to focus on actual learning, not just building schools. Long-term gains come from sustained improvement in instruction and curriculum.
9. What is labor market discrimination in the context of education?
Labor market discrimination occurs when employers treat workers differently based on characteristics like race, gender, or ethnicity rather than their actual skills. In the context of education, even if two workers have the same level of schooling, one may be paid less or hired less often because of bias. This discrimination reduces the return to education for the disadvantaged group. It can happen in hiring, promotions, or pay decisions. For example, studies have found that resumes with white-sounding names get more callbacks than identical ones with Black-sounding names, despite the same education. Discrimination thus weakens the link between education and earnings.
10. What does Arrow's impossibility theorem say?
Arrow's theorem states that no voting system can simultaneously satisfy a set of fairness conditions when there are three or more choices. The conditions include: no dictator (one person cannot decide everything), Pareto efficiency (if everyone prefers A over B, then A should win), independence of irrelevant alternatives (adding a third option shouldn't change the ranking between two), and universal domain (any preference order is allowed). Arrow proved that it is impossible for any voting method to meet all these criteria. This means every voting system has some flaw. For example, majority rule can lead to cycles. The theorem is a key result in social choice theory.
11. How does the technology of skill formation differ for cognitive vs noncognitive skills?
Cognitive skills are more sensitive to early childhood inputs, like nutrition and stimulation. They have a critical period: it is easier to build them in young children than in adolescents. Noncognitive skills are more malleable later in life, even during teenage years and adulthood. For example, a mentoring program for teens can improve self-control but may not boost IQ much. Also, cognitive skills are built by direct teaching and practice, while noncognitive skills often develop through experiences like sports, arts, or jobs. The process for noncognitive skills relies more on motivation and role models. Thus, the timing and type of intervention matter for each.
12. How can society try to resolve Sen's liberal paradox?
One way is to limit individual liberty in certain areas to achieve better overall outcomes. For example, society might agree that some personal choices, like reading a book, are not so important and can be overruled if they cause harm. Another way is to use a different decision rule, like allowing bargaining or side payments. People could trade their liberty: A pays B not to read the book. However, this might be seen as buying and selling rights. Some philosophers argue that liberty is more important than efficiency, so we should accept the paradox. Others suggest that the paradox is rare in real life and can be managed by separating personal from public choices.