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Does sharing the same class in school improve cognitive abilities of twins?
Dinand Webbink1, David Hay, Peter M Visscher
1CPB Netherlands Bureau for Economic Policy Analysis, The Hague, the Netherlands. h.d.webbink@cpb.nl
Summary
Separating twins in the classroom improves language skills in second grade, especially for same-sex pairs. Long-term separation also benefits opposite-sex twins
Area of Science:
- Developmental Psychology
- Educational Psychology
- Twin Studies
Background:
- The impact of classroom separation on twin development is a key area in educational psychology.
- Previous research has yielded mixed results, necessitating further investigation with robust methodologies.
Purpose of the Study:
- To analyze the cognitive effects of classroom separation for twins in Dutch primary education.
- To investigate how separation impacts language and arithmetic abilities at different developmental stages.
- To control for unobserved factors through advanced statistical methods in a longitudinal design.
Main Methods:
- Utilized a large, longitudinal, school-based sample of twins and their classmates.
- Employed statistical techniques to mitigate bias from nonrandom twin assignment and unobserved variables.
- Analyzed cognitive abilities, specifically language and arithmetic, across different primary school grades.
Main Results:
- Classroom separation significantly impacts second-grade language performance, with nonseparated twins scoring higher.
- This language advantage for nonseparated twins is more pronounced in same-sex pairs.
- Evidence suggests a potential benefit in arithmetic for nonseparated twins in second grade; however, no significant effects were found in higher grades, except for a positive impact on opposite-sex twins' language performance between grades 6 and 8 after at least 3 years of separation.
Conclusions:
- Classroom separation has a discernible effect on early language development in twins.
- The impact of separation varies by sex composition and duration.
- Further research is warranted to explore the long-term cognitive and academic trajectories of separated twins.
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