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## Portfolio theory and capital markets - William F. Sharpe - Google книги

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View Preview. Learn more Check out. Islamic Capital Markets: Theory and Practice. Related Information. Close Figure Viewer. An example would be two assets, X and Y. Based upon the past performance of both, we can assume that Asset X will continue to give out a higher return. This analysis makes the decision on what to invest in easier.

That being said the divergence is higher for Asset X and that must also be taken into consideration. This is a very basic example of the relationship between risk and return which indicates that one should only bear with a higher risk if there is an expectation that there will be a greater return. Now, the situation gets a little more complicated when the value of two deviations comes into the play.

Two assets can be thrown together in a portfolio to form a sort of correlation, i. We can use the previous example to make sense out of this. In the first year X shows a 1. In the second year X gives a higher return by 1. Our result will come out at 0. This helps us figure out the diversification of the two. We can after this further examine the portfolio and see how much of each, X and Y, the investors or fund managers want to add to their portfolio.

The best payoff would be when the correlation between the two would be -1 because then this would indicate that there are some set of portfolio weights which eliminate risk. Diversification is a handy tool because if you combine a higher returning asset to a lower risk asset than you increase your expected return.

You have not only made your portfolio more efficient because of the higher expected return but have also inadvertently made your investments a safer one. This is successfully achieved with assets whose correlation is relatively lower as compared to others Lumby, After diversification we come to multiple asset portfolios. An effective portfolio gives investors the highest amount of return on any given risk; to achieve this they can invest in a variety of different stocks at the same time. The size of the company that is selling its stocks and shares is not important; it is the return that the investors or fund managers should be keeping an eye at.

It would also be beneficial to diversify across markets, both international and domestically and get a hold of different kinds of assets e. If you have a well formed portfolio the basic idea is that there will be no haphazard risk attached to your investment. If not constructed properly, an ill managed portfolio can result in a great loss for the investing party.

It is also important to remember that most of the risk can be diversified and taken care of but that does not mean that risk diminishes completely Freeman, Stemming from the portfolio theory is another model that addresses the matters of equity. The Capital Asset Pricing Model CAPM delves into measuring the risk of an asset and to take that risk and then define the given price as per the required return.

## Beyond modern portfolio theory

The basic idea behind the CAPM is that there is some amount of risk that is associated with all assets in a capital market and this risk is not one that any investor can evade, this does not take into account the risk that the investor effectively avoids due to diversification.

Ergo what we look at through this model is the effect that leftover risk after diversification will have on the investment. This gives the investors and fund manager a clearer idea of what to expect. We assume that all investors will have to bear this risk and all investors only care about risk and return. It gives them a fair idea of the risk involved in the portfolio they are interested in buying Wormald et al.

go The main idea is that investors want to trade off both risk and return. Here we assume that the demand and supply of capital assets is equal, while the prices remain at equilibrium. The rate of lending is also taken to be the same as the rate of borrowing, whereby the risk, if any, if small because all loans are assumed to be returnable.

This is done to form some kind of solidity in the assumptions because otherwise the entire model would fluctuate and the results would be haphazard.

We set up the risks and returns of several portfolio possibilities to see the general effect. There will be a combination where no other assets will give out a better return at the same risk or a lower risk at the same return.

### RI Quarterly vol. 12: Highlights from the Academic Network Conference and PRI in Person 2017

This point would make the given portfolio a mean-variance efficient. The assumption is that is all borrowing and lending was suspended all investors would cling to the mean-variance efficient portfolios only, based on their own risk tolerance. Therefore being able to borrow and lend create the possibility to divide an investor's preference of risk and return from the prospects that exist in the capital market. In essence the result would be that each investor would acquire the same portfolio of risk based assets, however, the market portfolio and rise-free assets would be different for all.

There are some complications that come with the CAPM; to begin with the model cannot be put to an actual test because you can never define any portfolio will a complete and total precision for example you can never define the components of the portfolio to an accurate degree Armitage, i.

Can antiques be made part of the overall picture?