190 likes | 200 Views
School Accountability and the Distribution of Student Achievement. Randall Reback Barnard College Economics Department and Teachers College, Columbia University. No Child Left Behind.
E N D
School Accountability and the Distribution of Student Achievement Randall Reback Barnard College Economics Department and Teachers College, Columbia University
No Child Left Behind • States must adopt accountability systems that assign ratings to schools based on student pass rates on exams in elementary, middle school, and high school grades • School is not making ‘Adequate Yearly Progress’ if a pass rate is not sufficiently high, where the required pass rate increases each year • Consequences • Stigma, financial rewards/penalties, loss of local control, changes in property values • Intra-district public school choice provision • Tutoring for economically disadvantaged children
Texas Accountability Program • Precursor to No Child Left Behind • Assigns schools one of four ratings based on • Dropout Rates • Attendance Rates • Fraction of students who pass exams (overall and within subgroups by race and family income) • Testing Incentives are based on Pass Rates, not value-added measures of student-achievement
Previous Research Related to School Accountability/Minimum Proficiency • Relative performance of students at different points in distribution (Holmes, 2004; Deere & Strayer, 2001) • Achievement trends • Grissmer & Flanagan (98)- Math NAEP in TX • Hanushek & Raymond- Math NAEP • Carnoy, Loeb, Smith (2002)- TX improvements didn’t correspond with improved 10-12th grade transitions, SAT participation, SAT performance • Low-performing versus high-performing schools (Jacob, forthcoming • States with or without HS graduation exams (Jacobsen, 1993) • Gaming • Exemptions: Figlio & Getzler, Cullen & Reback • School meals: Figlio & Winicki • Disciplinary practices: Figlio
Theoretical Framework • Subject Specific but not Student Specific Inputs (as) • Not Subject Specific but Student Specific Inputs (bi) • Subject Specific and Student Specific Inputs (cs) • Assume only campus-wide Math (m) and Reading (r) pass rates count. Call all other subjects (z). Schools want to maximize:
The Data • Texas Assessment of Academic Skills • Math Tested Grades 3-8 and 10 • Writing Tested Grades 4, 8, and 10 • Test Documents Submitted for Every Student • Includes Student Descriptors • Campus Level Data on Attendance/Dropouts • Texas Learning Index • Measures How Student Performs Compared to Grade Level • I Do Not Measure Test Score Gains for Observations with Prior Year’s Scores Below 30 or Above 84
Pass Rate Probabilities Based on Prior Year Test Score Range Passing Score=70
Estimating the Marginal Benefit to the School from a Moderate Increase in a Student’s Expected Performance • estimate the probability that each student passes by grouping students based on their performance during other years • use these student-level pass probabilities to compute the probability that the school will obtain each rating • find the marginal effect of a moderate improvement in the expected achievement of a particular student on the probability that the school obtains the various ratings….
How a ‘moderate improvement’ in a student’s achievement is determined • hypothetical pass probability by re-estimating the student’s pass probability after dropping the bottom X% of the current year score distribution among students with identical prior year scores • For example: distribution of this year’s Math scores for students scoring 53 last year in Math 0%: 36 Actual pass probability= .20 20%: 49 40%: 55 60%: 59 Pass probability with X% set at 20%: 80%: 70 .2 / .8=.25 100%: 86
Dependent Variable • Year-to-year variation in test scores might be greater at certain points of achievement distribution • Value-added models examining distributional effects SHOULD NOT simply look at changes in levels or in relative place in distribution • Instead, use conditional Z-score… Z-score among students with similar prior year scores • This way, results are compared to typical progress at that place in the test score distribution
Empirical Model #1: Campus-Year Fixed Effects Student i in grade g during year y at school s • Si,t includes control variables for student characteristics: • Cubic terms for prior year scores in other subject • Racial dummy variables, Low-income family dummy, • and Race-income interactions
Achievement Gains and Marginal Accountability Incentives within Schools and within the Same Year
Model #2: Response to Infra-marginal Incentives (Cross-sectional comparisons) • Schools might consider the impact of improving the expected performance of 5% of the students • Define as the marginal change in the schools’ probability of a higher rating if all students in the ‘group’ are expected to do better
Achievement Gains and Infra-marginal Accountability Incentives
Model #3: Incentive to Improve Performance within a Grade-level • Schools might use inputs that simultaneously affect multiple students • Define as change in school’s probability of receiving a higher rating if all students in student i‘s grade at the school improve
Approximate Effect Sizes (SD change in Statewide Achievement Distribution from 1 SD increase in Accountability Incentive
Effects of Sample Selection Due to Student Exemptions & Grade Repetition • Exemptions • negative relationship between student-level accountability incentive and likelihood that student is exempted from accountability pool • suggests that estimated effect of student-level accountability incentive may understate the true effect • Also suggests that estimated effect of grade-level incentives overstate the effects for lowest achievers and understate for others • Grade Retention • small, positive relationship between the student-level accountability incentives and the probability of grade retention • effect on main results is unclear, but likely small
Conclusions • Schools respond to specific incentives of a rating system • Appear to respond with broad changes in teaching or resource allocation rather than narrowly-targeted changes • Current findings may understate distributional effects • High achievers (top 50% Reading, top 33% math) are not included • May be permanent changes rather than response to short-run incentives • NCLB-style ratings. Are they good? bad?... depends on one’s preferences.