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estimate. In addition, TMCIt is at best only a proxy for the cost of
inputs associated with wholesaling and processing raw-headless shrimp.
Reduced and final form estimates
The reduced form and final form coefficient and price flexiblity
estimates corresponding to the structural coefficient estimates for the
retail, wholesale, and ex-vessel price models were derived. The reduced
and final form estimates of the structural system describe each jointly
determined variable in terms of all predetermined variables. This
differs from the structural equations in that each structural equation
attempts to describe a specific part of the system being modeled in a
ceteris paribus fashion, while also taking into account all of the
interdependencies among the jointly determined variables. In addition,
structural estimates are only derived for varibles directly involved in
the part of the system represented by a given equation. Structural
estimates and reduced and final form estimates are measures of change in
the jointly determined variable given a change in a predetermined vari
able. The structural estimate, however, assumes all other predetermined
variables are constant in the current time period (partial effect),
while reduced and final form estimates represent an equilibrium after
all variables have been allowed to change. When lagged dependent varia
bles are present, the reduced form estimates are essentially an inter
mediate result, since effects of the lagged variables have not been
allowed enough time to work through the system. In this case, final
form estimates would be more appropriate for analysis. Lagged
endogenous variables (prices) exist in this study. Thus, the reduced
forms are presented only in Appendix D. The following discussion is
oriented toward the final form estimates.