Question 1

Find $\mathrm { P } ( \bar { X } > 2,510 )$
If ? = 2,500 and $\sigma _ { \bar { x } } = 7$

Accepted Answer

A) .0764 
B) .9998 
C) .9236 
D) .0001 
A) .0764 
B) .9998 
C) .9236 
D) .0001

Question 2

Sampling error occurs because of incomplete information.

Accepted Answer

A) True 
 B)False

Question 3

The number of defectives in 10 different samples of 50 observations each is the following: 5,1,1,2,3,3,1,4,2,3.What is the estimate of the population proportion of defectives?

Accepted Answer

A) .25 
B) .50 
C) .05 
D) .42 
A) .25 
B) .50 
C) .05 
D) .42

Question 4

The ___________ is a minimum-variance unbiased point estimate of the mean of a normally distributed population.

Accepted Answer

A) Sample mean 
B) Sample variance 
C) Sample standard deviation 
D) Observed mean 
A) Sample mean 
B) Sample variance 
C) Sample standard deviation 
D) Observed mean

Question 5

A minimum variance,unbiased point estimate has a variance that is as small as or smaller than the variances of any other unbiased point estimate.

Accepted Answer

A) True 
 B)False

Question 6

The standard deviation of the sampling distribution of the sample mean is σ.

Accepted Answer

A) True 
 B)False

Question 7

The sampling distribution of the sample mean is a normal distribution for ________ sample sizes,regardless of the shape of the corresponding population distribution.

Accepted Answer

A) Random 
B) Large 
C) Larger than 50 
D) Small 
A) Random 
B) Large 
C) Larger than 50 
D) Small

Question 8

The College Student Journal (December 1992)investigated differences in traditional and nontraditional students,where nontraditional students are defined as 25 years old or older and working.Based on the study results,we can assume the population mean and standard deviation for the GPA of nontraditional students are µ = 3.5 and ? = 0.5.Suppose a random sample of 100 nontraditional students is selected and each student's GPA is calculated.What is $\mu _ { \bar { x } }$?

Accepted Answer

A) 0.5 
B) 3.5 
C) 7.0 
D) 0.05 
A) 0.5 
B) 3.5 
C) 7.0 
D) 0.05

Question 9

A random sample of size 1,000 is taken from a population where p = .20.Find $\mathrm { P } ( \hat { p } < .22 )$

Accepted Answer

A) .2643 
B) .9429 
C) .9207 
D) .0571 
A) .2643 
B) .9429 
C) .9207 
D) .0571

Question 10

A random sample of size 1,000 is taken from a population where p = .20.Find $\mathrm { P } ( \hat { p } < .18 )$

Accepted Answer

A) .9429 
B) .0571 
C) .2643 
D) .0793 
A) .9429 
B) .0571 
C) .2643 
D) .0793

Question 11

The population of lengths of aluminum-coated steel sheets is normally distributed with a mean of 30.05 inches and a standard deviation of 0.2 inches.A sample of four metal sheets is randomly selected from a batch.What is the probability that the average length of a sheet is between 30.25 and 30.35 inches long?

Accepted Answer

A) .9773 
B) .0227 
C) .0386 
D) .0215 
A) .9773 
B) .0227 
C) .0386 
D) .0215

Question 12

A random sample of size 1,000 is taken from a population where p = .20.Find $\mathrm { P } ( \hat { p } > 175 )$

Accepted Answer

A) .9761 
B) .0239 
C) .0392 
D) .9999 
A) .9761 
B) .0239 
C) .0392 
D) .9999

Question 13

_____________ occurs when some population elements are excluded from the process of selecting the sample.

Accepted Answer

A) Nonresponse 
B) An error of observation 
C) Undercoverage 
D) Sampling error 
A) Nonresponse 
B) An error of observation 
C) Undercoverage 
D) Sampling error

Question 14

The spread of the sampling distribution of $\bar { X }$
Is ____________ the spread of the corresponding population distribution sampling distribution.

Accepted Answer

A) Larger than 
B) Smaller than 
C) The same as 
D) Exactly ½ 
A) Larger than 
B) Smaller than 
C) The same as 
D) Exactly ½

Question 15

Stratification can at times be combined with multistage cluster sampling to develop an appropriate sample.

Accepted Answer

A) True 
 B)False

Question 16

The standard deviation of all possible sample proportions increases as the sample size increases.

Accepted Answer

A) True 
 B)False

Question 17

As the sample size ___________,the standard deviation of the population of all sample proportions increases.

Accepted Answer

A) Increases 
B) Stays the same 
C) Is variable 
D) Decreases 
A) Increases 
B) Stays the same 
C) Is variable 
D) Decreases

Question 18

The College Student Journal (December 1992)investigated differences in traditional and nontraditional students,where nontraditional students are defined as 25 years old or older and working.Based on the study results,we can assume the population mean and standard deviation for the GPA of nontraditional students is µ = 3.5 and ? = 0.5.Suppose a random sample of 100 nontraditional students is selected and each student's GPA is calculated.Find the interval that contains 95.44 percent of the sample means for nontraditional students.

Accepted Answer

A)  $\left[ \begin{array} { l l } 
3.45 & 3.55
\end{array} \right]$ 
B)  $\left[ \begin{array} { l l } 
2.50 & 4.50
\end{array} \right]$ 
C)  $\left[ \begin{array} { l l } 
3.35 & 3.65
\end{array} \right]$ 
D)  $\left[ \begin{array} { l l } 
3.40 & 3.60
\end{array} \right]$ 
A)  $\left[ \begin{array} { l l } 
3.45 & 3.55
\end{array} \right]$ 
B)  $\left[ \begin{array} { l l } 
2.50 & 4.50
\end{array} \right]$ 
C)  $\left[ \begin{array} { l l } 
3.35 & 3.65
\end{array} \right]$ 
D)  $\left[ \begin{array} { l l } 
3.40 & 3.60
\end{array} \right]$

Question 19

The sampling distribution of the sample mean is developed by repeatedly taking samples of size n and computing the sample means and reporting the resulting sample means in the form of a probability distribution.

Accepted Answer

A) True 
 B)False

Question 20

Selecting a random sample is the only way to ensure that the information reflects the true population.

Accepted Answer

A) True 
 B)False

Find $\mathrm { P } ( \bar { X } > 2,510 )$ If ? = 2,500 and $\sigma _ { \bar { x } } = 7$

Sampling error occurs because of incomplete information.

The number of defectives in 10 different samples of 50 observations each is the following: 5,1,1,2,3,3,1,4,2,3.What is the estimate of the population proportion of defectives?

The ___________ is a minimum-variance unbiased point estimate of the mean of a normally distributed population.

A minimum variance,unbiased point estimate has a variance that is as small as or smaller than the variances of any other unbiased point estimate.

The standard deviation of the sampling distribution of the sample mean is σ.

The sampling distribution of the sample mean is a normal distribution for ________ sample sizes,regardless of the shape of the corresponding population distribution.

A random sample of size 1,000 is taken from a population where p = .20.Find $\mathrm { P } ( \hat { p } < .22 )$

A random sample of size 1,000 is taken from a population where p = .20.Find $\mathrm { P } ( \hat { p } < .18 )$

A random sample of size 1,000 is taken from a population where p = .20.Find $\mathrm { P } ( \hat { p } > 175 )$

_____________ occurs when some population elements are excluded from the process of selecting the sample.

The spread of the sampling distribution of $\bar { X }$ Is ____________ the spread of the corresponding population distribution sampling distribution.

Stratification can at times be combined with multistage cluster sampling to develop an appropriate sample.

The standard deviation of all possible sample proportions increases as the sample size increases.

As the sample size ___________,the standard deviation of the population of all sample proportions increases.

The sampling distribution of the sample mean is developed by repeatedly taking samples of size n and computing the sample means and reporting the resulting sample means in the form of a probability distribution.

Selecting a random sample is the only way to ensure that the information reflects the true population.

An Introduction to Business Statistics

Descriptive Statistics: Tabular and Graphical Methods

Descriptive Statistics: Numerical Methods

Probability

Discrete Random Variables

Continuous Random Variables

Confidence Intervals

Hypothesis Testing

Comparing Two Means and Two Proportions

Filters

Exam 7: Sampling and Sampling Distributions

Find P(Xˉ>2,510)\mathrm { P } ( \bar { X } > 2,510 )P(Xˉ>2,510) If ? = 2,500 and σxˉ=7\sigma _ { \bar { x } } = 7σxˉ​=7

Sampling error occurs because of incomplete information.

The number of defectives in 10 different samples of 50 observations each is the following: 5,1,1,2,3,3,1,4,2,3.What is the estimate of the population proportion of defectives?

The ___________ is a minimum-variance unbiased point estimate of the mean of a normally distributed population.

A minimum variance,unbiased point estimate has a variance that is as small as or smaller than the variances of any other unbiased point estimate.

The standard deviation of the sampling distribution of the sample mean is σ.

The sampling distribution of the sample mean is a normal distribution for ________ sample sizes,regardless of the shape of the corresponding population distribution.

A random sample of size 1,000 is taken from a population where p = .20.Find P(p^<.22)\mathrm { P } ( \hat { p } < .22 )P(p^​<.22)

A random sample of size 1,000 is taken from a population where p = .20.Find P(p^<.18)\mathrm { P } ( \hat { p } < .18 )P(p^​<.18)

A random sample of size 1,000 is taken from a population where p = .20.Find P(p^>175)\mathrm { P } ( \hat { p } > 175 )P(p^​>175)

_____________ occurs when some population elements are excluded from the process of selecting the sample.

The spread of the sampling distribution of Xˉ\bar { X }Xˉ Is ____________ the spread of the corresponding population distribution sampling distribution.

Stratification can at times be combined with multistage cluster sampling to develop an appropriate sample.

The standard deviation of all possible sample proportions increases as the sample size increases.

As the sample size ___________,the standard deviation of the population of all sample proportions increases.

The sampling distribution of the sample mean is developed by repeatedly taking samples of size n and computing the sample means and reporting the resulting sample means in the form of a probability distribution.

Selecting a random sample is the only way to ensure that the information reflects the true population.

An Introduction to Business Statistics

Descriptive Statistics: Tabular and Graphical Methods

Descriptive Statistics: Numerical Methods

Probability

Discrete Random Variables

Continuous Random Variables

Confidence Intervals

Hypothesis Testing

Comparing Two Means and Two Proportions

Filters

Find $\mathrm { P } ( \bar { X } > 2,510 )$ If ? = 2,500 and $\sigma _ { \bar { x } } = 7$

A random sample of size 1,000 is taken from a population where p = .20.Find $\mathrm { P } ( \hat { p } < .22 )$

A random sample of size 1,000 is taken from a population where p = .20.Find $\mathrm { P } ( \hat { p } < .18 )$

A random sample of size 1,000 is taken from a population where p = .20.Find $\mathrm { P } ( \hat { p } > 175 )$

The spread of the sampling distribution of $\bar { X }$ Is ____________ the spread of the corresponding population distribution sampling distribution.