The weekly returns of two portfolios were recorded for one year. Risk can be defined as the variation in returns. Are the two portfolios different in their risk factors at the .95 confidence level? The s statistic for the first portfolio is 0.1616 and for the second it is 0.2958 .

An important measure in service facilities such as banks or restaurants is the variability in service times. Two bank tellers were observed and the service times were recorded. Teller 1 served 100 customers and the s statistic for the service times was 3.0578 . Teller 2 served 75 customers and the s statistic was 3.3091 . Are the variabilities different at the .90 confidence level?