【正确答案】(1) The modern quantity theory of money refers to the monetary theory developed by the Chicago School. From the late 1940s through the 1990s, a group of economists, associated in varying degrees with Chicago School, build upon the traditions of classical economics with the benefit of modern theoretical and statistical techniques. Represented by Milton Friedman, originally labeled the Chicago School, but currently referred to either as monetarists or new classical macroeconomists, this informal group has produced a set of ideas with important implications for the role of money in the economy. In 1956, Friedman published his paper " The Quantity Theory of Money Demand—A Restatement", which marked the emergence of the modern quantity theory of money. On one hand, Friedman accepted the Cambridge School and Keynes’s thought that money is an asset and the demand for money is people’s behavior of choosing assets; on the other hand, Friedman basically adopted the conclusion of the traditional quantity theory of money, i. e., the change of the quantity of money is the cause of the movement of price level. 　　(2) In his design of the function of demand for money, Friedman took into consideration the two factors; first, the total wealth expressed with permanent income which is in a reverse ratio to the demand for money; second, the difference between expected rates of return of holding money and other assets. The higher the rate of return of other assets, the weaker people’s desire to hold money. Friedman did not analyze people’s motives of holding money like Keynes, but continued to study the causes of holding money and thought that there are many different factors affecting the demand for money. Friedman used a function to express the demand for money: 　　Md / P =f (Yp, Rm, Rb, Rf, P, W, U ) 　　Md / P: the demand for real money balances, 　　Yp; The real GDP, the index used to count wealth, called permanent income, 　　Rm; The expected rate of return for money, 　　Rb: The expected rate of return for bonds, 　　Re: The expected rate of return for stocks (common stocks), 　　P; The expected rate of return of goods or expected rate of inflation, 　　W; The ratio of non-human wealth to human wealth, 　　U; Other random variables, including preference, custom, technology, system, etc. 　　(3) In Friedman’s view, the wealth affecting the money demand is permanent and the money demand will not fluctuate with ups and downs of business cycles because the permanent income fluctuates a little in shortrun. Generally speaking, the demand for an asset has a positive interrelation with the wealth people hold. Since money is an asset, the demand for money has a positive interrelation with wealth (Yp). Friedman held that factors affecting money demand are the expected rate of return of the assets that can substitute money. Besides holding wealth in the form of money, people can hold their wealth in other forms, say, bonds, stocks (common stocks) and goods. The opportunity cost of holding money is expressed by the expected rate of return of other assets compared with money. When the expected rates of return of bonds (Rb) and stocks (Re) rise the opportunity cost of holding money will increase which will result in less demand for money. The higher the expected rate of return of other assets, the less the demand for money. P is the expected rate of return of holding wealth in the form of goods compared with money. When the prices of goods rise, the rate of return of goods equals the rate of inflation rate. When the expected rate of return of goods is higher compared with that of holding money, people will do well to "beat the higher prices" by purchasing goods sooner than usual (this is the "expectations effect"). This will reduce the demand for money. W is the ratio of non-human wealth to human wealth. Non-human wealth refers to bonds, stocks and other real assets, while human wealth refers to individuals’ ability to make money. This ratio constrains people’s income, e. g.; human wealth can not be obtained when labor force is in a state of unemployment, which naturally reduces the demand for money. Given certain level of wealth, the larger the W, the smaller the money demand. U which refers to other random variables is in a negative correlation with the money demand. 　　Monetarists adhere to virtually all the tenets of classical economists. However, they made some modifications. Some of them have used the quantity theory as a framework for describing the relationship between M and PY rather than just M and P and view the invisible hand as pushing the economy toward the full employment level of production. A second modification of classical thought occurred in Milton Friedman’s revival of the quantity theory is that Friedman replaced the idea of the stability of velocity with the less militant notion that it is predictable. Or, money demand may not be a fixed fraction of total spending; it is related to PY in a close and predictable way. 　　Perhaps the most important classical tradition upheld by modern monetarists is the inherent stability of the economy at full employment. This explains the monetarist rejection of governmental attempts to fine-tune economic activity. A higher level of economic activity requires more capital and labor or technological improvements; more money only leads to inflation. The answer to cyclical downturns is to wait for the natural upturn. Government intervention is unnecessary and potentially damaging.