Older and Wiser? Birth Order and IQ of Young Men

Kjell G Salvanes, Sandra Black and Paul Devereux

No 6375, CEPR Discussion Papers from C.E.P.R. Discussion Papers

Abstract: While recent research finds strong evidence that birth order affects children?s outcomes such as education and earnings, the evidence on the effects of birth order on IQ is decidedly mixed. This paper uses a large dataset on the population of Norway that allows us to precisely measure birth order effects on IQ using both cross-sectional and within-family methods. Importantly, irrespective of method, we find a strong and significant effect of birth order on IQ, and our results suggest that earlier born children have higher IQs. Our preferred estimates suggest differences between first-borns and second-borns of about one fifth of a standard deviation or approximately 3 IQ points. Despite these large average effects, birth order only explains about 3% of the within-family variance of IQ. When we control for birth endowments, the estimated birth order effects increase. Thus, our analysis suggests that birth order effects are not biologically determined. Also, there is no evidence that birth order effects occur because later-born children are more affected by family breakdown.

Keywords: Birth order; Human capital; Intelligence (search for similar items in EconPapers)
JEL-codes: J10 (search for similar items in EconPapers)
Date: 2007-07
New Economics Papers: this item is included in nep-edu
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (25)

Downloads: (external link)
https://cepr.org/publications/DP6375 (application/pdf)
CEPR Discussion Papers are free to download for our researchers, subscribers and members. If you fall into one of these categories but have trouble downloading our papers, please contact us at subscribers@cepr.org

Related works:
Journal Article: Older and Wiser? Birth Order and IQ of Young Men (2011)
Working Paper: Older and Wiser? Birth Order and IQ of Young Men (2007)
Working Paper: Older and Wiser? Birth Order and IQ of Young Men (2007)
Working Paper: Older and wiser? Birth order and IQ of young men (2007)
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:cpr:ceprdp:6375

Ordering information: This working paper can be ordered from
https://cepr.org/publications/DP6375

Access Statistics for this paper

More papers in CEPR Discussion Papers from C.E.P.R. Discussion Papers Centre for Economic Policy Research, 33 Great Sutton Street, London EC1V 0DX.
Bibliographic data for series maintained by ().