1. Which of the following is a fundamental difference between a t statistic and a z-score?
a.The t statistic uses the sample mean in place of the population
mean.
b.The t statistic uses the sample variance in place of the population
variance.
c.The t statistic computes the standard error by dividing the
standard deviation by n - 1 instead of dividing by n.
d.None of these are differences between t and z.
2. Which bit of information is not obtainable from the results of a t-test written up in a statistical
report?
a.the alpha level used in the hypothesis test
b.whether the null hypothesis is rejected or fails to be rejected
c.the degrees of freedom used in the hypothesis test
d.Each of these bits of information is obtainable from the results of a
t-test written up in a statistical report.
3. Why are t statistics more variable than z-scores?
a.The extra variability is caused by variations in the sample mean.
b.The extra variability is caused by variations in the sample
variance.
c.The extra variability is caused by variations in the population
mean.
d.The extra variability is caused by variations in experimental
control.
4. Under what circumstances can a very small treatment effect be statistically significant?
a.if the sample size is large and the sample variance is small
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