Albrecht, James W. (contributor); … - 2005
)butitfacilitatestheexposition. Let
Y
i,t
=g(X
i
,t)+V
i
+δ(U
i
,V
i
,X
i
)I(Z
i,t
>0)+ε
i,t
(1)
account of changes in aggregate conditions.
4
See … Bergemann, Fitzenberger and Speckesser (2004) and Blundell et al. (2004) for applica-
tions.
12
where X
i
are observed … explanatory variables, g is an unknown function, U
i
and
V
i
are individual-specific effects (which may depend on X
i
), δ is the …