Measuring Portfolio Risks
One of the concepts used in risk and return calculations is standard deviation which measures the dispersion of actual returns around the expected return of an investment. Since standard deviation is the square root of the variance, this is another crucial concept to know. The variance is calculated by weighting each possible dispersion by its relative probability (take the difference between the actual return and the expected return, then square the number).

The standard deviation of an investment's expected return is considered a basic measure of risk. If two potential investments had the same expected return, the one with the lower standard deviation would be considered to have less potential risk.

Risk Measures
There are three other risk measures used to predict volatility and return:
• Alpha - this measures stock price volatility based on the specific characteristics of the particular security. As with beta, the higher the number, the higher the risk.

• Sharpe ratio- this is a more complex measure that uses the standard deviation of a stock or portfolio to measure volatility. This calculation measures the incremental reward of assuming incremental risk. The larger the Sharpe ratio, the greater the potential return. The formula is: Sharpe Ratio = (total return minus the risk-free rate of return) divided by the standard deviation of the portfolio.

• Beta - this measures stock price volatility based solely on general market movements. Typically, the market as a whole is assigned a beta of 1.0. So, a stock or a portfolio with a beta higher than 1.0 is predicted to have a higher risk and, potentially, a higher return than the market. Conversely, if a stock (or fund) had a beta of .85, this would indicate that if the market increased by 10%, this stock (or fund) would likely return only 8.5%. However, if the market dropped 10%, this stock would likely drop only 8.5%.

• Learn how to properly use beta to help meet your portfolio's risk criteria in the article, Beta: Gauging Price Fluctuations.
Asset Allocation
In simple terms, asset allocation refers to the balance between growth-oriented and income-oriented investments in a portfolio. This allows the investor to take advantage of the risk/reward tradeoff and benefit from both growth and income. Here are the basic steps to asset allocation:

1. Choosing which asset classes to include (stocks, bonds, money market, real estate, precious metals, etc.)
2. Selecting the ideal percentage (the target) to allocate to each asset class
3. Identifying an acceptable range within that target
4. Diversifying within each asset class
If you are unfamiliar with asset allocation, refer to the tutorial: Asset Allocation.

Risk Tolerance
The client's risk tolerance is the single most important factor in choosing an asset allocation. At times, there may be a distinct difference between the risk tolerance of a client and his/her spouse, so care must be taken to get agreement on how to proceed. Also, risk tolerance may change over time, so it's important to revisit the topic periodically.

Time Horizon
Clearly, the time horizon for each of the client's goals will affect the asset allocation mix. Take the example of a client with a very aggressive risk tolerance. The recommended allocation to stocks will be much higher for the client's retirement portfolio than for the money being set aside for the college fund of the client's 13-year-old child.
Strategic vs. Tactical Asset Allocation

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