Economic Theories of Fertility. Beyond Malthus. Thomas Malthus (early 19C). fertility determined by the age at marriage and frequency of coition during marriage. an increase in people’s income would encourage them to marry earlier and have sexual intercourse more often.
C0 is the parents’ real expenditure on children.
(qfC-qfZ)dln(wf) where pC=pZ=1 (numeraire)
dln(NQ) = CSyYdln(y) +
SiY=wi(T-tjc-tjz)/Y, j=m,f, are shares of full income.
qHC=wmH/CNQ, qMC=wmh(M)/CNQ, SC=CNQ/Y and now SmY=wm(T-H-tmz)/Y.
E(U)=u(y-cb) + g(b,s).