Final answer:
The t-statistic is appropriate to use over the z-statistic when we don't know the population standard deviation, the sample size is small (less than 30), and the data follows a normal distribution.
Step-by-step explanation:
The t-statistic is appropriate to use over the z-statistic when:
- We don't know the population standard deviation.
- The sample size is small (less than 30).
- The data follows a normal distribution.
The t-statistic is calculated by subtracting the population mean estimate from the sample mean and dividing it by the standard error of the sample mean. It is used to test hypotheses and determine if the sample mean is significantly different from the population mean.