Regression discontinuity design framework for estimating intervention effects at a cutoff¶

Theory · All theories
Evidence · 3 claims (3 for) · 2 studies (1 causal, 1 theoretical), q2–q3 · 0 of 2 report an effect size · 3 claims rest on one study

Description¶

The document describes the RD design as a method for obtaining unbiased estimates of education intervention effects when a continuous scoring rule assigns units to treatment or comparison around a pre-set cutoff. The effect is estimated as the difference between the treatment and comparison regression lines at the cutoff: "an effect occurs if there is a 'discontinuity' in the two regression lines at the cutoff." The estimate pertains to units right at the cutoff.

Design Implications¶

Context¶

Requirements¶

• The relationship between the outcome and forcing variable can be modeled correctly
• The forcing variable was not manipulated to influence treatment assignments

Constraints¶

• The estimate pertains to average treatment effects for units right at the cutoff, not the full score range

Target Learners¶

• students
• schools
• school districts

Target Learning Objectives¶

• unbiased estimation of effects of education-related interventions

Claims¶

• Robust RDD methods protect against model misspecification but require much larger sample sizes to detect small effects [+W]
• Offering SES to eligible applicants near the cutoff in oversubscribed districts has no statistically significant impact on reading or math achievement [+W]
• Participating in SES (averaging about 21 hours) shows no statistically significant impact on reading or math achievement for students near the cutoff [+W]

Related Theories¶

Examples¶

• Use regression discontinuity designs to replicate or check experimental impact estimates for education interventions
• Regression discontinuity design exploiting oversubscription rationing of SEdS

Key Sources¶

• Schochet, P., Cook, T., Deke, J., Imbens, G., Lockwood, J.R., Porter, J., Smith, J. (2010). Standards for Regression Discontinuity Designs. Retrieved from What Works Clearinghouse website: http://ies.ed.gov/ncee/wwc/pdf/wwc_rd.pdf.