18
III. Comparative Effects of Demographics, Socioeconomic Status on White
Characteristics
Nineteenth century soldiers and prisoner statures were related to age, birth years,
occupations, migration, and nativity. They may have also been related to insolation,
which is the primary source of vitamin D production (Holick, 2007 video). We test
which of these variables were associated with stature, and separate regressions are run on
the military and prison samples. To start, soldiers and prisoners are partitioned into
separate groups, and the ith soldier and prisoner statures are assumed to be related with
age, birth period, occupation, migration, nativity, and insolation.
50 1839 4 6
Centimeteri = α+ ∑βa Agei,a + ∑ βtBirthi,t + ∑ βlOccupationi,l + ∑βn Nativityi,n
a=15 t=1800 l=1 n=1
+βMigMigrationi,Mig+βIsolInsoli,Insol+βInsol2Insoli2,Insol2 +εi
Dummy variables are included for youth ages 15 through 22; adult age dummies
are included for 40 and 50 year old age intervals. Birth decade dummies are in ten year
intervals from 1800 through 1849. Dummy variables are included for white-collar,
skilled, and agricultural occupations. Nativity dummy variables are included for birth in
Northeast, Middle-Atlantic, Plains, Southeast, and Southwest regions. Lastly, continuous
insolation and insolation squared terms are included to account for insolation and vitamin
D production.
Tables 4 and 5’s Model 1 includes unrestricted age, birth, occupations, nativity
variables, and continuous insolation variables. This unrestricted model is then compared
in Models 2 through 5 to restricted models for insolation, socioeconomic status, birth
periods, and nativity.