Key Research Findings on Teacher Quality and Education Economics
Key Research Findings in Education
Teacher Value Added (VA) and Causality
Chetty, Friedman & Rockoff: VA is Causal
- Criticism of VA: Traditional VA is criticized because good students might be assigned to good teachers (selection bias).
- Methodology: Quasi-experiment using teacher entry/exit shocks. Test scores rise when a high-VA teacher enters (and vice versa).
- Findings: Teacher VA is causal and affects long-term outcomes, such as earnings and graduation rates.
Jackson: Traditional VA is Insufficient
- Measurement Issue: Traditional VA captures only test gains.
- Missing Factors: Teachers also affect non-cognitive skills (e.g., attendance, effort, behavior), which predict long-term success.
- Recommendation: VA measures should include both cognitive and non-cognitive effects.
Goldhaber: Characteristics of Effective Teachers
- Credentials are poor predictors of teacher quality.
- Unobserved traits matter more: communication, authority, expectations, and motivation.
Teacher Labor Market Dynamics
Corcoran: Evolution of Women in Teaching
- Mid-20th Century: Top female graduates concentrated in teaching due to limited alternatives.
- Later Evolution: As women entered law, medicine, and STEM, fewer top graduates chose teaching.
- Societal Impact: Gender equality and expanded professional opportunities reduced the supply of top talent in teaching.
Teacher Compensation: Temin vs. Vedder
Debate on whether teachers are overpaid, based on the lens used:
- Temin (Underpaid): Compares teacher pay to their opportunity cost (what similarly skilled people earn elsewhere—comparable worth).
- Vedder (Potentially Overpaid): Considers total compensation (benefits, pensions, vacations) alongside strong supply, suggesting market equilibrium might indicate overpayment.
Peer Effects and School Structure
Carrell & Hoekstra: Peer Effects Matter
- Peers shape student behavior and motivation within the classroom.
- Disruptive Peers: Students exposed to domestic violence cause large, negative, causal effects on the entire class; peer effects are asymmetric.
- Other effects include role models and peer tutoring.
Dynarski: Effects of Exam Schools
- Exam schools are often seen as engines of excellence.
- Regression Discontinuity Finding: Students just above or below the cutoff perform similarly.
- Exam schools do not inherently improve outcomes; observed gains are mostly due to selection and peer sorting.
College Investment and Costs
Avery & Turner: Student Loans and Returns
- Education Bubble? No. The college wage premium remains large, indicating strong returns on investment.
- Degree Value: The degree functions as both a productivity enhancer and a signal of ability.
- Borrowing Patterns: Low-income students often borrow too little (due to debt fear/misinformation); high-income students borrow more easily.
Archibald & Feldman: Rising College Costs
- Cost Drivers: Education is labor-intensive, leading to slow productivity growth (cost disease).
- Price Drivers: Competition causes universities to raise sticker prices for amenities and services; net prices rise more slowly.
- Bennett Hypothesis: Increased financial aid can lead to higher tuition if supply is inelastic and universities revenue-maximize.
ECO-C: Admissions Interventions
- A light-touch informational intervention (providing net costs, eligible colleges, fee waivers) is cheap, scalable, and has large effects on reducing undermatching.
Summary of Key Takeaways
Accountability and Teacher Quality
Harris & Deming
- NCLB failed; proper accountability design requires measuring growth (VAM).
- Schools respond differently to accountability; better system design is needed to capture long-term impacts.
Teacher Value and Skills
Chetty et al., Jackson, Goldhaber
- Teacher VA is causal and impacts long-term success.
- VA must incorporate non-cognitive skills.
- Unobserved traits, not credentials, define the best teachers.
Labor Market and Compensation
Corcoran, Temin, Vedder
- The teacher labor market lost top female talent as other careers opened.
- Teacher pay depends on whether one compares to opportunity cost (underpaid) or market equilibrium (potentially overpaid).
Student Environment and Selection
Carrell & Hoekstra, Dynarski
- Disruptive peers cause significant negative effects on the whole class.
- Exam school success is largely due to student selection, not the school itself.
Higher Education Finance
Avery & Turner, Archibald & Feldman, ECO-C
- College remains a strong investment; low-income students need support to borrow adequately.
- Rising costs are structural (cost disease), though competition shapes final prices.
- Simple information interventions effectively reduce undermatching.