With Guaranteed Pass Solutions.
Which of the following is not a form of bias? - Answer Information from the sample is typical
of information in the population.
Nonresponse bias occurs when __________. - Answer those responding to a survey or poll
differ systematically from the nonrespondents
A simple random sample is a sample of n observations that has the same probability of being
selected from the population as any other sample of n observations. - Answer True
Social-desirability bias refers to systematic difference between a group's "socially acceptable"
responses to a survey or poll and this group's ultimate choice. - Answer True
We use a population parameter to make inferences about a sample statistic. - Answer False
John would like to conduct a survey in his neighborhood to get homeowners' opinion on the
Delmarva proposal to switch to natural gas. Which of the following is an example of a stratified
sample? - Answer John divides the population into two-story, split-level, and ranch houses.
Then, he selects a proportional number of houses from each group.
Which of the following meets the requirements of a cluster sample? - Answer A population
can be divided into 50 city blocks. The sample will include residents from two randomly chosen
city blocks.
A survey is designed to collect data on students' evaluations of their instructor's teaching
performance. Which of the following situations most likely results in social-desirability biases? -
Answer The survey is administered in class with the instructor in the room the entire time.
In cluster sampling, the population is first divided up into mutually exclusive and collectively
exhaustive groups, called clusters. A cluster sample includes randomly selected observations
from each cluster, which are proportional to the cluster's size in the population. - Answer False
When a statistic is used to estimate a parameter, the statistic is referred to as an estimator. A
, convenience sample? - Answer Peggy selects the first 25 homes that she passes as she walks
into the entrance of the development.
Cluster sampling is preferred when the objective is to increase precision. - Answer False
Which of the following meets the requirements of a stratified random sample of size 6? -
Answer A population contains 10 members under the age of 25 and 20 members over the age
of 25. The sample will include two people chosen at random under the age of 25 and four
people chosen at random over 25.
Bias can occur in sampling. Bias refers to __________. - Answer the tendency of a sample
statistic to systematically overestimate or underestimate a population parameter
A parameter is a random variable, whereas a sample statistic is a constant. - Answer False
According to a survey, high school students average 100 text messages daily. Assume that the
population standard deviation is 20 text messages. Suppose a random sample of 36 high school
students is taken.
a. What is the probability that the sample mean is more than 105?
b. What is the probability that the sample mean is less than 95?
c. What is the probability that the sample mean is between 95 and 105? - Answer a. 0.0668
In Excel: =1 - NORM.DIST(105, 100, 20/SQRT(36), TRUE)
b. 0.0668
In Excel: =NORM.DIST(95, 100, 20/SQRT(36), TRUE)
c. 0.8664
In Excel: =NORM.DIST(105, 100, 20/SQRT(36), TRUE) - NORM.DIST(95, 100, 20/SQRT(36), TRUE)
Beer bottles are filled so that they contain an average of 345 ml of beer in each bottle. Suppose
that the amount of beer in a bottle is normally distributed with a standard deviation of 7 ml.
a. What is the probability that a randomly selected bottle will have less than 339 ml of beer?