assignment: Ch3 Quiz
Consider the following population of five numbers: 5, 7, 12, 14, 15. Calculate the range, variance, and standard deviation of this population. (Round variance to 2 decimal places, round standard deviation to 4 decimal places.)
Standard deviation σ
The Morningstar Top Fund lists at the Morningstar.com website give the mean yearly return and the standard deviation of the returns for each of the listed funds. As given by Morningstar.com on March 17, 2005, the RS Internet Age Fund has a mean yearly return of 11.93 percent with a standard deviation of 41.96 percent; the Franklin Income A fund has a mean yearly return of 14 percent with a standard deviation of 9.36 percent; the Jacob Internet fund has a mean yearly return of 37.60 percent with a standard deviation of 41.16 percent.
(a) For each mutual fund, find an interval in which you would expect 95.44 percent of all yearly returns to fall. Assume returns are normally distributed. (Round your answers to 2 decimal places. A negative sign should be used instead of parentheses.)
RS Internet Age Fund: [ , ]
Franklin Income A Fund: [ , ]
Jacob Internet Fund: [ , ]
(b) Using the intervals you computed in part a, compare the three mutual funds with respect to average yearly returns and with respect to variability of returns.
RS has the lowest average and the highest variability.
Franklin has the middle average and the lowest variability.
Jacob has the highest average return and the middle variability.
(c) Calculate the coefficient of variation for each mutual fund, and use your results to compare the funds with respect to risk. Which fund is riskier? (Round your answers to 2 decimal places. A negative sign should be used instead of parentheses.)
RS Internet Age Fund: Coefficient of Variation = %
Franklin Income A Fund: Coefficient of Variation = %
Jacob Internet Fund: Coefficient of Variation = %
RS Internet is riskiest, Jacob is second and Franklin is least risky.
Suppose that 20 randomly selected customers give the following satisfaction ratings (on a scale of 1 to 10) for a DVD recorder.
2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 10 10
Find the median, the first quartile, and the third quartile for these data.
0 out of
Which percentile describes the third quartile, Q3?
If one intends to compare the relative variation between two samples involving two different quantitative variables with different measurement scales, then the most appropriate way is to compare the two samples’ :
Coefficient of variations