country , the factor endowment vector for country , and the country 's share of the world consumption and the world total endowment vector of factors. For many countries and many factors, it is possible to estimate the left hand sides and right hand sides independently. To put it another way, the left hand side tells the direction of factor service trade. Thus it is possible to ask how this system of equations holds. The results obtained by Bowen, Leamer and Sveiskaus (1987) were disastrous. They examined the cases of 12 factors and 27 countries for the year 1967. They found that the two sides of the equations had the same sign only for 61% of 324 cases. For the year 1983, the result was more disastrous. Both sides had the same sign only for 148 cases out of 297 cases (or the rate of correct predictions was 49.8%). The results of Bowen, Leamer, and Sveiskaus (1987) mean that the Heckscher–Ohlin–Vanek (HOV) theory has no predictive power concerning the direction of trade. Criticism The critical assumption of the Heckscher–Ohlin model is that the two countries are identical, except for the difference in resource endowments. This also implies that the aggregate preferences are the same. The relative abundance in capital leads the capital-abundant country to produce the capital-intensive good cheaper than the labor-abundant country, and vice versa. Initially, when the countries are not trading: The price of the capital-intensive good in the capital-abundant country will be bid down relative to the price of the good in the other country, the price of the labor-intensive good in the labor-abundant country will be bid down relative to the price of the good in the other country. Once trade is allowed, profit-seeking firms move their products to the markets that have (temporary) higher prices. As a result: the capital-abundant country will export the capital-intensive good, the labor-abundant country will export the labor-intensive good. Poor predictive power The original Heckscher–Ohlin model and extended model such as the Vanek model performs poorly, as it is shown in the section "Econometric testing of H–O model theorems". Daniel Trefler and Susan Chun Zhu summarizes their paper that "It is hard to believe that factor endowments theory [editor's note: in other words, Heckscher–Ohlin–Vanek Model] could offer an adequate explanation of international trade patterns". A common understanding exists that in the national level HOV model fits well. In fact, Davis