A computer manufacturer estimates that its line of minicomputers has, on average, 8.4 days of downtime...
A computer manufacturer estimates that its line of minicomputers
has, on average, 8.4 days of downtime per year. To test this claim,
a researcher contacts seven companies that own one of these
computers and is allowed to access company computer records. It is
determined that, for the sample, the average number of downtime
days is 5.5, with a sample standard deviation of 1.4 days. Assuming
that number of downtime days is normally distributed, test to
determine whether these minicomputers actually average 8.4 days of
downtime in the entire population. Let α = .01.
What is the value of test statistics?
We are reject the null hypothesis or we fail to reject the hypothesis?
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