children other than their own. The age restriction is imposed in order to remove the majority
of individuals in retirement or still actively pursuing their studies as these activities
(particularly educational activities which are classified as tertiary) are not well modeled in our
analysis. The restriction on household composition is imposed because it is not clear who is
chiefly responsible for non-own children. A small number of individuals missing information
on key demographic variables (age, education, gender) are excluded. These restrictions yield
samples of 1,143 households in Denmark and 23,877 households in the US.
Both surveys asked respondents to complete time diaries in which they identify in
their own words what they were doing over the course of a 24 hour period. One household
member was chosen at random to complete a single diary in the US with half the diaries
completed for a weekend and half for a weekday day. In Denmark each partner was asked to
complete two diaries, one for a weekday and one for a weekend day. These diaries were
completed orally using a fully flexible time frame in the case of the US survey, while the
Danish respondents were asked to provide a written record of their activities in ten minute
intervals. In both cases we restrict our analysis to those diaries missing no more than one
hour’s worth of activity and including at least five distinct activity spells. Incomplete diaries
and diaries with few activity reports are believed to be of low quality (Juster 1985). Our goal
here is to obtain „good’ data on time use and, in fact, fewer than five percent of all the diaries
fail to meet these conditions.
In an effort to limit the analysis to reasonably „normal’ days, we have also excluded
diaries indicating more than four hours of „sickness’ or over twenty hours of sickness or
sleep-related activities. This restriction is binding for less than one percent of the sample.
Rather than rely on the weekend/weekday designation to distinguish between work days and
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