Suppose a population consisted of 20 items. How many different samples of n = 3 are possible?
We wish to develop a confidence interval for the population mean. The population follows the normal distribution, the standard deviation of the population is 3, and we have a sample of 10 observations. We decide to use the 90% level of confidence. The appropriate value of to represent the level of confidence is
B. z =1.65
A confidence interval
A. Always includes the population parameter.
B. Decreases in width as the sample size is increased.
C. Cannot include a value of 0
D. None of these
Which of the following statements is not a characteristic of the t distribution?
A. Like z there is only one t distribution.
B. It is a continuous distribution.
C. It is symmetrical.
D. It has a mean of 0.
Answers of multiple choice questions on hypothesis testing and confidence interval