, ST 311 NCSU – Exam 1 Multiple Choice Practice & Study Guide.
1. A normal distribution is... symmetric
2. In a simple random sample, the problem of non-
re- sponse bias occurs when... Some individuals that are
randomly selected refuse
to participate
3. A certain firm has 500 employees. An auditor
wishes to estimate the average number of days
of sick leave taken per employee over the past A cluster sample using the
quarter. The firm has eight divisions, with varying divisions as clusters.
numbers of employees per division. The auditor
decides to randomly sample 3 divisions and finds
the number of sick days each employee within
these divisions take.
This sample is best described as:
4. Suppose a random sample of size n = 35 is taken from Both samples.
population A and a random sample of size n = 20 is
tak- en from population B. In which case would it
be valid to use the standard normal distribution to
make prob- ability calculations concerning these
sample means?
5. A local corporation was interested in the A. All Wake County
purchasing habits of Wake County residents. One resi- dents.
of the things they were interested in was the
proportion of residents
that did a major home improvement project in the last B. The proportion of all
year. The corporation used a list of all households Wake County residents
in the county to take a simple random sample.
The re- searcher then visited each of the sampled who did a major home im-
homes and found that 21 of 100 homes had provement. project in the
completed a major home improvement project. last year.
A. What is the population of interest in this
C. The list of all households
situation?
in the county