Demand+technological change+imperfect competition+economies of scale+significant differences between international trade and traditional trade theories.

The new trade theory: demand+technological change+imperfect competition+economies of scale+international trade is actually a new trade theory, which explains intra-industry trade.

Traditional trade theory: traditional trade theory explains inter-industry trade.

Second, the differences in assumptions:

New trade theory: The assumption of the new trade theory is that the market is not completely competitive.

Traditional trade theory: The premise of traditional trade theory is complete market competition.

Third, the differences in research angles:

New trade theory: the new trade theory not only studies from the perspective of supply, but also explains from the perspective of demand.

Traditional trade theory: traditional trade theory is studied from the perspective of supply.

Fourth, the focus is different:

New trade theory: The new trade theory emphasizes the role of differentiated products in international trade.

Traditional trade theory: Traditional trade theory assumes that all products are homogeneous.