Question

A shareholders' group is lodging a protest against your company. The shareholders group claimed that the mean tenure for a chief exective office (CEO) was at least 9 years. A survey of 72 companies reported in The Wall Street Journal found a sample mean tenure of 8.6 years for CEOs with a standard deviation of s=s= 5.1 years (The Wall Street Journal, January 2, 2007). You don't know the population standard deviation but can assume it is normally distributed.

You want to formulate and test a hypothesis that can be used to challenge the validity of the claim made by the group, at a significance level of α=0.005α=0.005. Your hypotheses are:

      Ho:μ=9Ho:μ=9
      Ha:μ<9Ha:μ<9

What is the test statistic for this sample?
test statistic =  (Report answer accurate to 3 decimal places.)

What is the p-value for this sample?
p-value =  (Report answer accurate to 4 decimal places.)  

The p-value is...

• less than (or equal to) αα
• greater than αα

This test statistic leads to a decision to...

• reject the null
• accept the null
• fail to reject the null

As such, the final conclusion is that...

• There is sufficient evidence to warrant rejection of the claim that the population mean is less than 9.
• There is not sufficient evidence to warrant rejection of the claim that the population mean is less than 9.
• The sample data support the claim that the population mean is less than 9.
• There is not sufficient sample evidence to support the claim that the population mean is less than 9.

Answer 1