The first assumption we make is that there are no transaction coast . there is no cost friction of buying or selling any asset .if transaction costs were present, the return from any asset would be a function of whether or not the investor owned it before the decision period .thus, to include transaction costs in the model adds a great deal of complexity. Whether it is worthwhile introducing this complexity depends on the importance of transaction costs to investors' decision .given the size of transaction costs ,they are probably of minor importance.
The second assumption behind the capm is that assets are infinity divisible. This means that investors could take any position in an investment, regardless of the size of their wealth.
The third assumption is the absence of personal income tax. This means, for example that the individual is indifferent to the form in which the return on the investment is received.
The fourth assumption is that an individual cannot affect the price of a stock by his buying or selling action .this is analogous to the assumption of perfect competition . while no single investor can affect prices by an individual action ,investor in total determine prices by their actions.
The fifth assumption is that investors are expected to make decision solely in term of expected value and standard deviation of the returns on their portfolio ..
The sixth assumption is unlimited lending and borrowing at the riskless rate . the investor can be lend or borrow any amount of funds desired at a rate of interest equal to the rate for riskless securities .
The eighth and ninth assumptions deal with the homogeneity of expectations. First ,investors are assumed to be concerned with the mean and variance of returns and all investors are assumed to define the relevant period in exactly the same manner. Second , all investors are assumed to have identical expectation with respect to the necessary inputs to the portfolio decision
The tenth assumption is that all assets are marketable . all assets, including human capital can be sold and bought on the market.
استاذي العزيز هل تساعدني في صياغه هذي بشكل مبسط
المفضلات