Skip to Main Content

We next ask whether this cognitive shock impacted labor market outcomes differently for men and women. Table 4 reports the results of two separate regressions: one for women (panel A) and one for men (panel B), along with the difference in our main coefficients across the two specifications (panel C). Stark gender differences are apparent.5 All of the positive effects on labor supply and income, reported in the previous tables, are driven by women. In fact, there are no significant coefficients in the male regressions, and for labor force participation and income, the after interaction coefficients are significantly larger for women than for men.

Table 4.
Effects of Salt Iodization on Labor and Income Outcomes, By Gender
(1)(2)(3)(4)
1(Employed)1(Participated in the Labor Force)1(Worked at least 40 weeks)sinh$-1$(Income)
A. Females
After $×$ Goiter Rate 0.0108*** 0.0121*** 0.0144*** 0.149***
(0.00360) (0.00395) (0.00525) (0.0505)
During $×$ Goiter Rate 0.00519 0.00579 0.0206*** 0.0192
(0.00372) (0.00405) (0.00466) (0.0398)
Observations 1,236,420 1,236,420 606,704 1,108,650
Mean of dependent variable 0.429 0.448 0.659 5.586
B. Males
After $×$ Goiter Rate 0.00197 0.000148 0.00562 0.0288
(0.00392) (0.00364) (0.00443) (0.0173)
During $×$ Goiter Rate 0.000934 −0.000487 0.000888 0.0116
(0.00237) (0.00247) (0.00384) (0.0240)
Observations 1,146,723 1,146,723 930,299 1,026,746
Mean of dependent variable 0.872 0.905 0.867 10.38
C. Female-male difference
After $×$ Goiter Rate 0.00884 0.0119** 0.00874 0.120**
(0.00576) (0.00521) (0.00592) (0.0504)
During $×$ Goiter Rate 0.00425 0.00628 0.0197*** 0.00759
(0.00464) (0.00516) (0.00658) (0.0424)
(1)(2)(3)(4)
1(Employed)1(Participated in the Labor Force)1(Worked at least 40 weeks)sinh$-1$(Income)
A. Females
After $×$ Goiter Rate 0.0108*** 0.0121*** 0.0144*** 0.149***
(0.00360) (0.00395) (0.00525) (0.0505)
During $×$ Goiter Rate 0.00519 0.00579 0.0206*** 0.0192
(0.00372) (0.00405) (0.00466) (0.0398)
Observations 1,236,420 1,236,420 606,704 1,108,650
Mean of dependent variable 0.429 0.448 0.659 5.586
B. Males
After $×$ Goiter Rate 0.00197 0.000148 0.00562 0.0288
(0.00392) (0.00364) (0.00443) (0.0173)
During $×$ Goiter Rate 0.000934 −0.000487 0.000888 0.0116
(0.00237) (0.00247) (0.00384) (0.0240)
Observations 1,146,723 1,146,723 930,299 1,026,746
Mean of dependent variable 0.872 0.905 0.867 10.38
C. Female-male difference
After $×$ Goiter Rate 0.00884 0.0119** 0.00874 0.120**
(0.00576) (0.00521) (0.00592) (0.0504)
During $×$ Goiter Rate 0.00425 0.00628 0.0197*** 0.00759
(0.00464) (0.00516) (0.00658) (0.0424)

Standard errors, clustered by state of birth, in parentheses ***p < 0.01, **p < 0.05, and *p < 0.1. “Goiter Rate” is the goiter rate in the individual's state of birth from Love and Davenport (1920), scaled by the difference between the 75th and 25th percentile of the goiter distribution (0.71). “After” is a dummy equal to 1 for those born 1928 to 1931. “During” is a dummy equal to 1 for those born 1924 to 1927. These regressions use the 1950–1980 censuses, restricting to individuals born from 1920 to 1931. All regressions include state of birth fixed effects; year of birth $×$ census year dummies; census division of birth $×$ birth year dummies; gender; race; and during and after dummies interacted with average state latitude and 1920 state-level female and black proportions. “1(Worked at least 40 weeks)” is conditional on having worked in the past year. “sinh$-1$(Income)” takes the inverse hyperbolic sine of total income, including 0 s for those not working.

Close Modal