Contact: Scott Carrell, University of California–Davis, (530) 302-1038
STANFORD -- Children exposed to domestic violence not only have more disciplinary problems at school, they perform considerably worse in math and reading than other students. They also have a negative effect on their classroom peers, resulting in decreased test scores and increased disciplinary problems according to a new study by economists Scott Carrell of the University of California–Davisand Mark Hoekstra of the University of Pittsburgh, published in the summer issue of Education Next.
Carrell and Hoekstra find that adding one troubled student to a classroom of 20 students decreases student reading and math test scores by more than two-thirds of a percentile point and increases misbehavior among other students in the classroom by 16 percent.
The researchers found that troubled peers have a large and statistically significant negative effect on the math and reading achievement of higher income children, but only a small and statistically insignificant effect on the achievement of low-income children. The pattern is opposite for disciplinary outcomes. The presence of troubled peers increases problem behavior of low-income children, but does not significantly increase the disciplinary problems of higher income children.
Carrell and Hoekstra also found that the effect differed by race and gender. The negative test-score effect is large and statistically significant for white boys, but statistically insignificant for black boys. The test-score effects on girls are negligible regardless of race. Disciplinary problems, however, increase for all subgroups except white girls. The effects are largest for black girls. One troubled peer added to a classroom of 20 students increases the probability that a black girl commits a disciplinary infraction by as much as 10 percent.
Carrell and Hoekstra also examined whether troubled boys affect their peers differently than do troubled girls. Across all outcome variables, both academic and behavioral, the negative peer effects appear to be driven primarily by the troubled boys, and these effects are largest on other boys in the classroom.
The results indicate that adding one troubled boy to a classroom of 20 students increases the probability that a boy will commit a disciplinary infraction by 17 percent and decreases boys’ test scores by nearly 2 percentile points -- or 7 percent of a standard deviation -- each year.
“These findings have important implications for both education and social policy,” Carrell and Hoekstra said. “Any policies or interventions that help improve the family environment of the most troubled students may have larger benefits than we have previously anticipated.”
Carrell and Hoekstra worked with a confidential student-level data set that consists of observations of students in grades 3 through 5 from 22 public schools over the period 1995–2003 in a district of roughly 30,000 students. The student population in the sample is approximately 55 percent white, 38 percent black, 3.5 percent Hispanic, 2.5 percent Asian, and 1 percent mixed race. Fifty-three percent of students were eligible for the federal free or reduced-price lunch program.
Carrell and Hoekstra also had access to yearly disciplinary records, which include incident type and date and were available for every student in their sample. They gathered domestic violence data from public records information, which include the date filed and the names and addresses of individuals involved in domestic violence cases filed in civil court between 1993 and 2003.
Scott Carrell is assistant professor of economics at the University of California–Davis. Mark Hoekstra is assistant professor of economics at the University of Pittsburgh.
Education Next is a scholarly journal published by the Hoover Institution that is committed to looking at hard facts about school reform. Other sponsoring institutions are the Harvard Program on Education Policy and Governance and the Thomas B. Fordham Foundation.