- For the standard normal distribution, compute Z0.69.
Use Excel and round the answer to two decimal places.
- Consider the following test performed with the level of
significance 0.01: A random sample of size 28 is obtained from a
normally distributed population. The population standard deviation
is equal to 3.6. The sample mean happened to be 24. For this
hypothesis test, what will be the critical value (the relevant
z-alpha)? Round the answer to three decimal
- A probability distribution of all possible sample proportions
of a given sample size is called the sampling distribution of the
- Select the false statement.
a. When t-numbers are used for computing the width of a
confidence interval, the corresponding Student's t-distribution
follows (n-1) degrees of freedom, where n is the sample size.
b. One should use z-numbers when estimating the population
c. When one knows the standard deviation of the population, one
must use t-numbers to determine the width of a confidence
d. If all other relevant variables are kept the same, than the
bigger the sample size, the narrower the confidence interval