question

When doing research, knowing the population mean and other population parameters is essential
A. True
B. False

answer

B. False

question

It is often not feasible to study the entire population because it is impossible to observe all the items in the population
A. true
B. False

answer

A. true

question

To study the population of consumer perceptions of new technology, sampling of the population is preferred over surveying the population because_____.
A. sampling is more accurate
B. we can compute z-scores
C. it is quicker
D. sampling methods are simple

answer

C. it is quicker

question

When testing the safety of cars using crash tests, a sample of one or two cars is used because ______.
A. sampling is more accurate
B. cars are destroyed
C. it is quicker
D. the population is very large

answer

B. cars are destroyed

question

A marketing firm is studying consumer preferences for winter fashions in four different months. From a population of women 18-21 years of age, a random sample of 100 women was selected in January. Another random sample of 100 women was selected in March. Another random sample of 100 women was selected in June. Another random sample of 100 women was selected in September. What is the sample size?
A. 4
B. 100
C. 400
D. 1

answer

B. 100

question

When all the items in a population have an equal chance of being selected for a sample, the process is called _____.
A. simple random sampling
B. z-score
C. sampling error
D. non-probability sampling

answer

A. simple random sampling

question

What is the difference between a sample mean and the population mean called?
A. standard error of the mean
B. sampling error
C. interval estimate
D. point estimate

answer

B. sampling error

question

Suppose we select every fifth invoice in a file. What type of sampling is this?
A. random
B. cluster
C. stratified
D. systematic

answer

D. systematic

question

All possible samples of size n are selected for a population and the mean of each sample is determined. What is the mean of the sample?
A. the population mean
B. it is larger than the population mean
C. it is smaller than the population mean
D. it cannot be estimated in advance

answer

A. the population mean

question

When dividing a population into subgroups so that a random sample from each subgroup can be collected, what type of sampling is used?
A. simple random sampling
B. systematic sampling
C. stratified random sampling
D. cluster sampling

answer

C. stratified random sampling

question

the true sampling error is usually not known because ______.
A. µ is unknown
B. µ is a random variable
C. ?2 is unknown
D. the sample mean canoe be computed

answer

A. µ is unknown

question

The size of the sampling error is _____.
A. directly related to the sample size-- in other words, the larger the sample size, the larger the sampling error
B. directly related to the population mean-- in other words, the larger the mean, the larger the sampling error
C. inversely related to the sample size-- in other words, the larger the sample size, the smaller the sampling error
D. inversely related to the population mean-- in other words, the smaller the standard deviation, the larger the sampling error

answer

C. inversely related to the sample size00 in other words, the larger the sample size, the smaller the sampling error

question

The mean of all sample means is ______.
A. X bar
B. µ
C. ?
D. ?

answer

B. µ

question

For a given population, the mean of all sample means (X bar) of sample size n, and the mean of all (N) population observations (X) are ______.
A. equal to (X bar)
B. not equal
C. equal to ( x bar - mu)
D. equal to the population mean µ

answer

D. equal to the population mean µ

question

Sampling error is defined as _______.
A (X bar - mu)
B. ?
C. ?/n
D. N - n

answer

A. (X bar - mu)

question

For a distribution of sample means constructed by sampling 5 items from a population of 15, ______.
A. the sample size is 15
B. there will be 3.003 possible sample means
C. the mean of the sample means will be 3
D. the standard error will be 1

answer

B. there will be 3,003 possible sample means

question

As the size of the sample increases, what happens to the shape of the distribution of sample means?
A. it cannot be predicted in advance
B. it approaches a normal distribution
C. it is positively skewed
D. it is negatively skewed

answer

B. it approaches a normal distribution

question

According to the central limit theorem _____.
A the population mean and the mean of all sample means are equal
B. increasing sample size decreases the dispersion of the sampling distribution
C. the sampling distribution of the sample means is approximately normally rD. the sampling distribution of the sample means will be skewed

answer

C. the sampling distribution of the sample means is approximately normally distributed

question

Manufacturers were subdivided into groups by volume of sales. Those with more than $100 million in sales were classified as large; those from $50 to $100 million as medium size; and those between $25 and $50 million, and so on. Samples were then selected from each of these groups. What is this type of sampling called?
A. simple random sampling
B. stratified random sampling
C. cluster sampling
D. systematic sampling

answer

B. stratified random sampling

question

A statewide sample survey is to be made. First, the state is subdivided into counties. Seven counties are selected at random and further sampling is concentrated on these seven counties. What type of sampling is this?
A. simple random
B. systematic random sampling
C. cluster sampling
D. stratified sampling

answer

C. cluster sampling

question

Which of the following is the standard error of the mean?
A. ?
B. x/n
C. ?/ SqRt(n)
D. s

answer

C. ?/ SqRt(n)

question

Mileage tests were conducted on a randomly selected sample of 100 newly developed automobile tires. the mean tread wear was 50,000 miles, with a standard deviation of 3,500 miles. What is the best estimate of the average tread life in miles for the entire population of these tires?
A. 50,000
B. 3,500
C. 500
D. 35

answer

A. 50,000

question

Sampling error is the difference between a sample statistic and its corresponding _____.
A. sample mean
B. variance
C. population parameter
D. trend

answer

C. population parameter