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Sibling Ideological Influence: A Natural Experiment

Published online by Cambridge University Press:  25 March 2011

R. Urbatsch
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Abstract

Siblings are a potentially important source of political socialization. Influence is common, especially among younger siblings and those close in age, who tend to interact most frequently. This suggests that the positions of an individual's next-older sibling will hold particular sway. In policy questions with a gender gap, then, those whose immediately older sibling is a sister will be more likely to absorb the typically female preference; those born after a brother, the male preference. Evidence from the United States shows that this pattern holds for general left–right orientation as well as for the preferred balance between public and private sectors. Just as American women are more likely to lean left and to see government intervention positively, so are Americans whose next-older sibling is female.

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Research Article
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British Journal of Political Science , Volume 41 , Issue 4 , October 2011 , pp. 693 - 712
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Copyright © Cambridge University Press 2011

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66 Combining the non-farm countryside category with the farm category does not appreciably alter the reported results.

67 All respondents living abroad at age 16 are grouped into a single category with its own indicator.

68 Other potentially interesting factors, such as direct measures of parental views and how they might have shaped both the respondent's and sibling's outlook, are not available in this dataset.

69 Ordered logistic regressions produce substantively similar results for all OLS regressions in this study; OLS models are retained for ease of interpretation.

70 As both the sex variable and the sibling-sex variable are simple indicators, these estimated effects are simply the size of the coefficients (in points on the seven-point scale).

71 Education is less consistent in its effects, probably because of collinearity with income.

72 Despite its lack of statistical significance, the effect of sibling sex here is still substantively non-trivial. The coefficients imply that the difference between an older brother and an older sister roughly equals the effect of a fifteen-year change in age.

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76 Siblings’ months of birth are not available.

77 Unprocessed, the median respondent's age difference with the next-older sibling is two years, just over half the mean age difference of 3.45 years; the maximum difference is thirty-one years.

78 Similar results hold for using the models without income and education.

79 All four models of Table 2 produce comparable results if run with the interaction term: a continued negative coefficient for having a next-older sister, and smaller positive coefficients for the interaction.

80 This range includes 96.5 per cent of the observed values in the dataset.

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