samlet årgang - Økonomisk Institut - Københavns Universitet

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NATIONALØKONOMISK TIDSSKRIFT 2005. NR. 3
5.1. Do deviations between expected and realised earnings trigger divorce?
In the present data set there is no information that provides a clear cut answer to whether
realised earnings were actually expected or not. As an approximation to this I use the
predicted earnings from a Mincer earnings regression as a proxy for expected earnings
and subsequently test whether larger differences between the predicted earnings and the
realised earnings are related to divorce risk. The results in Table 3 suggest they are. Marriages
where the husband experiences a positive income shock are more likely to survive.
The opposite is the case if 1) the husband experiences a negative income shock or
2) if there are changes in the wife’s earnings in either a positive or negative direction. For
wives the effect of positive income differences have the highest impact on the divorce
hazard. A mayor drawback of this analysis is that I treat earnings as an exogenous variable.
There are good reasons to expect that earnings are endogeneous to divorce risk.
Weiss (1997) argues that spouses’ earnings and children are potentially endogenous to
the divorce decision from a dynamic model of defensive investments. In the model, fertility
and child quality requires inputs of time and money by parents in the first period,
and child quality requires inputs of time and money by parents in the second period.
Also, parents’ wages in the second period depend on how much they worked in the first
period due to learning-by-doing in the labour market. In the second period, new information
is available which could induce the dissolution of the marriage. Hence, fertility
in the first period, wages in the second period and the probability of divorce are jointly
determined.
Weiss and Willis (1997) address the endogeneity of earnings explicitly. After endogenising
earnings they find that if the husband experiences a positive surprise then the
divorce probability decreases, whereas the divorce probability increases if the wife experiences
a positive surprise in earnings. I do not endogenize earnings, but the results
are similar.
That asymmetries exist in terms of earnings and behaviour of husbands and wives is
also found by Lentz and Tranæs (2004). They find that the job finding effort of married
men and women is affected by the income of their spouses in opposite directions. For
women, spouse income influences job finding negatively, just as own wealth does: the
more the man earns and the wealthier the woman is, the longer it takes for her to find a
job. The contrary is the case for men, where spouse income affects job finding positively:
the more the wife earns, the faster the husband finds a job. This is so despite the
fact that greater own wealth also prolongs unemployment spells for men.
5.2. Premarital cohabitation and divorce risk
I find that premarital cohabitation is negatively correlated with divorce risk. This
result is not new (see Svarer (2004)). What is new, however, is that the finding still pre-