Erratum to: Why Is Infant Mortality Higher in Boys Than in Girls? A New Hypothesis Based on Preconception Environment and Evidence From a Large Sample of Twins

Erratum to: Demography

DOI 10.1007/s13524-012-0161-5

Because of an error introduced at typesetting, four of the equations in the article were not presented properly; the coefficient (π) of X _hyt was omitted in Eqs. (2), (2)′, (3), and (4)′. They should have been presented as follows:

$$ {{\mathrm{M}}_{\mathrm{i}\mathrm{hyt}}}={\uptheta_{\mathrm{SF}\ \mathrm{E}}}\;\mathrm{M}\ \mathrm{al}{{\mathrm{e}}_{\mathrm{i}}} + {{\mathrm{X}}_{\mathrm{h}\mathrm{y}\mathrm{t}}}\uppi + {{\mathrm{u}}_{\mathrm{h}}} + {{\mathrm{p}}_{\mathrm{h}\mathrm{y}}} + {{\mathrm{w}}_{\mathrm{i}\mathrm{hyt}}} $$

(2)

$$ {{\mathrm{M}}_{\mathrm{j}\mathrm{hy}}}{\prime_{\mathrm{t}}} = {\uptheta_{\mathrm{SF}\ \mathrm{E}}}\;\mathrm{M}\;\mathrm{al}{{\mathrm{e}}_{\mathrm{j}}} + {{\mathrm{X}}_{\mathrm{h}\mathrm{y}}}{\prime_{{t}}}\uppi + {{\mathrm{u}}_{\mathrm{h}}} + {{\mathrm{p}}_{\mathrm{h}\mathrm{y}}}\prime + {{\mathrm{w}}_{\mathrm{j}\mathrm{hy}}}{\prime_{\mathrm{t}}} $$

(2')

$$ {{\mathrm{M}}_{\mathrm{i}\mathrm{hy}\mathrm{t}}}-{{\mathrm{M}}_{\mathrm{j}\mathrm{hy}}}{\prime_{\mathrm{t}}} = {\uptheta_{\mathrm{SF}\ \mathrm{E}}}\;(\mathrm{M}\;\mathrm{al}{{\mathrm{e}}_{\mathrm{i}}}-\mathrm{M}\;\mathrm{al}{{\mathrm{e}}_{\mathrm{j}}}) + ({{\mathrm{X}}_{\mathrm{hy}\mathrm{t}}}-{{\mathrm{X}}_{\mathrm{hy}}}{\prime_{\mathrm{t}}})\uppi + {{\mathrm{p}}_{\mathrm{hy}}}-{{\mathrm{p}}_{\mathrm{hy}}}\prime + {{\mathrm{w}}_{\mathrm{i}\mathrm{hy}\mathrm{t}}}-{{\mathrm{w}}_{\mathrm{j}\mathrm{hy}}}{\prime_{{t}}}. $$

(3)

$$ {{\mathrm{M}}_{{-\mathrm{i}\mathrm{hy}}}}{\prime_{\mathrm{t}}} = \mathrm{M}\;\mathrm{al}{{\mathrm{e}}_{{-\mathrm{i}}}}{\uptheta_{{\mathrm{T}\;\mathrm{F}\;\mathrm{E}}}} + {{\mathrm{X}}_{\mathrm{h}\mathrm{y}}}{\prime_{\mathrm{t}}}\uppi + {{\mathrm{u}}_{\mathrm{h}}} + {{\mathrm{p}}_{\mathrm{h}\mathrm{y}}}\prime + {{\mathrm{w}}_{{-\mathrm{i}\mathrm{hy}}}}{\prime_{\mathrm{t}}}. $$

(4')

Additional corrections are as follows:

• 1. In footnote 3, "male-emale" should be "male-female."

• 2. In footnote 11, "(Olivier 2006" should be "(Olivier 2006)."

• 3. In the notes below Table 4, "country-year fixed effect" should be removed from the list of controls, given that it appears in the table.

• 4. On page 14, in the second sentence of the first paragraph, "during to the postneonatal period" should be "during the postneonatal period."