Demographic variables tend to have various directions of influence on farm work
duration for each legal status. Being female has a significantly positive effect on duration for
authorized and citizen workers, while it has a significantly negative effect for permanent resident
workers and no significant effect for unauthorized workers. Marriage has a significantly positive
effect on duration for authorized and permanent resident workers, while it has a significantly
negative effect for citizen workers. Permanent resident and citizen Hispanic workers tend to have
shorter farm work duration than non-Hispanic workers, while unauthorized and authorized
Hispanic workers tend to have longer farm work duration than non-Hispanic workers. Education
has a significantly positive effect on the duration for all legal status, and experience has a
significantly positive effect on the duration for unauthorized and authorized workers, but no
significant effect on permanent resident or citizen workers. Age has a significant nonlinear effect
on duration for all equations. The effect is positive up to an age of 87 years for unauthorized, and
up to 105 years for citizen workers. On the other hand, the effect is negative through 39 years for
authorized, and continuously for permanent resident workers (not turning positive until age 199
years).
Next, using estimates of each equation, we calculate the predicted durations of farm work
by legal status by averaging the predictions over all observations for each equation (Table 4). The
results indicate that the average predicted duration for unauthorized workers is not necessarily
shorter than those for legal workers (authorized, permanent resident, or citizen). Actually, its
average predicted duration is the second longest, and longer than for permanent resident and
citizen workers.
Finally, we implement a simulation to test how farm work duration of a typical
unauthorized worker would be expected to change with a change in legal status. This approach
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