FROM DEMAND EQUATIONS TO TWO REGIMES: THE THEORETICAL DEVELOPMENT OF EXPORT MODELS.

Over the last fifty years or so, a great deal of attention has been paid to the estimation of time-series models of foreign trade flows - especially those relating to the volume of trade in imperfectly substitutable goods between one country and the rest of the world. In this time, the models employed have evolved from relatively simple demand equations through to more complex simultaneous- equation and two-regime approaches. The aim of this paper is to survey the developments that have been made and suggest some directions for future research by highlighting the weaknesses of the approaches currently available. [ABSTRACT FROM AUTHOR]