The characteristics and advantages of input-output analysis are that it can be used to study practical economic problems. It is a quantitative and systematic method to study the relationship between different departments in complex economic entities. This economic entity can be as big as a country, even the whole world, as small as the economy of a province, city and enterprise sector.
Economic forecasting is the most widely used input-output method. It is also an important application of input-output analysis to study what impact the implementation of an economic policy will have on the social economy. Input-output analysis can also be used to study some special social problems, such as environmental pollution, population and world economic structure. It was not until Vernon put forward the "product cycle theory" in 1966 that the "Leontief mystery" was solved. In Vernon's view, scientific and technological innovation plays a very important role in foreign trade, that is, the initial monopoly advantage of innovative products and the loss of monopoly advantage formed after technology transfer and diffusion determine the pattern change of international trade, thus promoting the evolution of a country's industrial structure.
This can be seen more clearly from the change of American industrial structure. Since 1980s, American government has increased its support for R&; D (research and development) support. 1994 American r&; D development investment reached $654.38+073.02 billion, surpassing Japan and Germany in R&D; D The total investment (US$ 6,543.8+US$ 070.74 billion) accounts for 2. 1% of the US GDP. In this way, the contribution rate of high-tech industries to American economic growth has increased from about 1986 ~ 14% in 19 1 ~ 1995 to more than 28% in/kloc-0. After technological transformation, the competitiveness of traditional industries such as American automobiles has also generally improved. From 1986 to 1995, the proportion of knowledge products exported by the United States in its total exports increased from 12% to 42%. Leontief and other foreign economists fully affirmed the enthusiasm and scientificity of Das Kapital's theory on the economic contradictions and laws of movement in capitalist society. Leontief pointed out: "Before trying to make any explanation, if a person wants to know what the profits and wages of capitalist enterprises are actually, then the information he can get from the three volumes of Das Kapital will be better than that he can find in the tenth issue of the American Statistical Census, dozens of textbooks on contemporary economic system, and even, I dare say, all the papers of Thorstein Van Buren."