20. Investing: Socially Responsible Mutual Funds Pax World Balanced is a highly respected, socially responsible mutual fund of stocks and bonds (see Viewpoint). Vanguard Balanced Index is another highly regarded fund that represents the entire U.S. stock and bond market (an index fund). The mean and standard deviation of annualized percent returns are shown below. The annualized mean and standard deviation are for a recent 10-year period (Source: Fund Reports). Pax World Balanced: x 9.58%; s = 14.05% Vanguard Balanced Index: x 9.02%; s = 12.50% (a) Interpretation Compute the coefficient of variation for each fund. Ifx represents return and s represents risk, then explain why the coefficient of variation can be taken to represent risk per unit of return. From this point of view, which fund appears to be better? Explain. (b) Interpretation Compute a 75% Chebyshev interval around the mean for each fund. Use the intervals to compare the two funds. As usual, past per- formance does not guarantee future performance.

U.S. Civilian Labor Force (thousands) Year Labor Force   Year Labor Force 2007 153,918   2012 155,628 2008 154,655   2013 155,151 2009 153,111   2014 156,238 2010 153,650   2015 157,957 2011 153,995   2016 159,640   1. Fit three trend models: linear, exponential, and quadratic. Which model would offer the most believable forecasts? 2. Make forecasts using the following fitted trend models for years 2017-2019. t          Exponential 11 12 13

8. Magazine Sales The following table shows the income, measured in thousands of dollars, from sales of a certain magazine at the start of the given year.