Question 1

As the sample size increases,the t-distribution becomes more similar to the ________ distribution.

Accepted Answer

A)  normal 
B)  exponential 
C)  multinominal 
D)  chi-square 
E)  binomial 
A)  normal 
B)  exponential 
C)  multinominal 
D)  chi-square 
E)  binomial

Question 2

The chi-square distribution for developing a confidence interval for a standard deviation has degrees of freedom.

Accepted Answer

A)  n + 2 
B)  n +1 
C)  n 
D)  n - 1 
E)  n - 2 
A)  n + 2 
B)  n +1 
C)  n 
D)  n - 1 
E)  n - 2

Question 3

If you are constructing a confidence interval for a single mean,the confidence interval will with an increase in the sample size.

Accepted Answer

A)  decrease 
B)  increase 
C)  stay the same 
D)  increase or decrease,depending on the sample data 
A)  decrease 
B)  increase 
C)  stay the same 
D)  increase or decrease,depending on the sample data

Question 4

Suppose there are 500 accounts in a population.You sample 50 of them and find a sample mean of $500.What would be your estimate for the population total?

Accepted Answer

A)  $5,000 
B)  $50,000 
C)  $250,000 
D)  $500,000 
E)  None of these choices 
A)  $5,000 
B)  $50,000 
C)  $250,000 
D)  $500,000 
E)  None of these choices

Question 5

The upper limit of the 90% confidence interval for the population proportion p,given that n = 100;and $\hat { P }$ 
= 0.20 is 0.2658.

Accepted Answer

A) True 
 B)False

Question 6

If two samples contain the same number of observations,then the data must be paired.

Accepted Answer

A) True 
 B)False

Question 7

A parameter such as $\sigma$
Is sometimes referred to as a ________ parameter,because many times we need its value even though it is not the parameter of primary interest.

Accepted Answer

A)  special 
B)  random 
C)  nuisance 
D)  independent 
E)  dependent 
A)  special 
B)  random 
C)  nuisance 
D)  independent 
E)  dependent

Question 8

The t-distribution and the standard normal distribution are practically indistinguishable as the degrees of freedom increase.

Accepted Answer

A) True 
 B)False

Question 9

There are,generally speaking,two types of statistical inference.They are:

Accepted Answer

A)  sample estimation and population estimation 
B)  confidence interval estimation and hypothesis testing 
C)  interval estimation for a mean and point estimation for a proportion 
D)  independent sample estimation and dependent sample estimation 
E)  None of these choices 
A)  sample estimation and population estimation 
B)  confidence interval estimation and hypothesis testing 
C)  interval estimation for a mean and point estimation for a proportion 
D)  independent sample estimation and dependent sample estimation 
E)  None of these choices

Question 10

We can form a confidence interval for the population total T by finding a confidence interval for the population mean $\mu$ 
in the usual way,and then multiplying the lower and upper limits the confidence interval by the population size N.

Accepted Answer

A) True 
 B)False

Question 11

If two random samples of size 40 each are selected independently from two populations whose variances are 35 and 45,then the standard error of the sampling distribution of the sample mean difference, $x _ { 1 } - x _ { 2 }$ 
,equals 1.4142.

Accepted Answer

A) True 
 B)False

Question 12

In developing a confidence interval for the population standard deviation $\sigma$ 
,we make use of the fact that the sampling distribution of the sample standard deviation s is not the normal distribution or the t-distribution,but rather a right-skewed distribution called the chi-square distribution,which (for this procedure)has n - 1 degrees of freedom.

Accepted Answer

A) True 
 B)False

Question 13

For a given confidence level,the procedure for controlling interval length usually begins with the specification of

Accepted Answer

A)  the point estimate 
B)  the population standard deviation,s 
C)  the sample standard deviation,s 
D)  the interval half-length,B 
A)  the point estimate 
B)  the population standard deviation,s 
C)  the sample standard deviation,s 
D)  the interval half-length,B

Question 14

If two random samples of sizes 30 and 35 are selected independently from two populations whose means are 85 and 90,then the mean of the sampling distribution of the sample mean difference, $x _ { 1 } - x _ { 2 }$ 
,equals 5.

Accepted Answer

A) True 
 B)False

Question 15

A 90% confidence interval estimate for a population mean $\mu$ 
is determined to be 72.8 to 79.6.If the confidence level is reduced to 80%,the confidence interval for $\mu$ 
becomes narrower.

Accepted Answer

A) True 
 B)False

Question 16

The interval estimate 18.5 $\pm$ 
2.5 was developed for a population mean when the sample standard deviation s was 7.5.Had s equaled 15,the interval estimate would be 37 $\pm$ 
5.0.

Accepted Answer

A) True 
 B)False

Question 17

The mean of the sampling distribution of the sample proportion $\hat { p }$ 
,when the sample size n = 100 and the population proportion p = 0.15,is 15.0.

Accepted Answer

A) True 
 B)False

Question 18

The lower limit of the 95% confidence interval for the population proportion p,given that n = 300;and $\hat { p }$ 
= 0.10 is 0.1339.

Accepted Answer

A) True 
 B)False

Question 19

If we cannot make the strong assumption that the variances of two samples are equal,then we must use the pooled standard deviation in calculating the standard error of a difference between the means.

Accepted Answer

A) True 
 B)False

Question 20

The approximate standard error of the point estimate of the population total is $N s / \sqrt { n }$ .

Accepted Answer

A) True 
 B)False

As the sample size increases,the t-distribution becomes more similar to the ________ distribution.

The chi-square distribution for developing a confidence interval for a standard deviation has degrees of freedom.

If you are constructing a confidence interval for a single mean,the confidence interval will with an increase in the sample size.

Suppose there are 500 accounts in a population.You sample 50 of them and find a sample mean of $500.What would be your estimate for the population total?

The upper limit of the 90% confidence interval for the population proportion p,given that n = 100;and $\hat { P }$ = 0.20 is 0.2658.

If two samples contain the same number of observations,then the data must be paired.

A parameter such as $\sigma$ Is sometimes referred to as a ________ parameter,because many times we need its value even though it is not the parameter of primary interest.

The t-distribution and the standard normal distribution are practically indistinguishable as the degrees of freedom increase.

There are,generally speaking,two types of statistical inference.They are:

We can form a confidence interval for the population total T by finding a confidence interval for the population mean $\mu$ in the usual way,and then multiplying the lower and upper limits the confidence interval by the population size N.

If two random samples of size 40 each are selected independently from two populations whose variances are 35 and 45,then the standard error of the sampling distribution of the sample mean difference, $x _ { 1 } - x _ { 2 }$ ,equals 1.4142.

For a given confidence level,the procedure for controlling interval length usually begins with the specification of

If two random samples of sizes 30 and 35 are selected independently from two populations whose means are 85 and 90,then the mean of the sampling distribution of the sample mean difference, $x _ { 1 } - x _ { 2 }$ ,equals 5.

A 90% confidence interval estimate for a population mean $\mu$ is determined to be 72.8 to 79.6.If the confidence level is reduced to 80%,the confidence interval for $\mu$ becomes narrower.

The interval estimate 18.5 $\pm$ 2.5 was developed for a population mean when the sample standard deviation s was 7.5.Had s equaled 15,the interval estimate would be 37 $\pm$ 5.0.

The mean of the sampling distribution of the sample proportion $\hat { p }$ ,when the sample size n = 100 and the population proportion p = 0.15,is 15.0.

The lower limit of the 95% confidence interval for the population proportion p,given that n = 300;and $\hat { p }$ = 0.10 is 0.1339.

If we cannot make the strong assumption that the variances of two samples are equal,then we must use the pooled standard deviation in calculating the standard error of a difference between the means.

The approximate standard error of the point estimate of the population total is $N s / \sqrt { n }$ .

Introduction to Data Analysis and Decision Making

Describing the Distribution of a Single Variable

Finding Relationships Among Variables

Probability and Probability Distributions

Normal, Binomial, Poisson, and Exponential Distributions

Decision Making Under Uncertainty

Sampling and Sampling Distributions

Hypothesis Testing

Regression Analysis: Estimating Relationships

Regression Analysis: Statistical Inference

Time Series Analysis and Forecasting

Introduction to Optimization Modeling

Optimization Models

Introduction to Simulation Modeling

Simulation Models

Data Mining

Importing Data Into Excel

Analysis of Variance and Experimental Design

Statistical Process Control

Filters

Exam 8: Confidence Interval Estimation

As the sample size increases,the t-distribution becomes more similar to the ________ distribution.

The chi-square distribution for developing a confidence interval for a standard deviation has degrees of freedom.

If you are constructing a confidence interval for a single mean,the confidence interval will with an increase in the sample size.

Suppose there are 500 accounts in a population.You sample 50 of them and find a sample mean of $500.What would be your estimate for the population total?

The upper limit of the 90% confidence interval for the population proportion p,given that n = 100;and P^\hat { P }P^ = 0.20 is 0.2658.

If two samples contain the same number of observations,then the data must be paired.

A parameter such as σ\sigmaσ Is sometimes referred to as a ________ parameter,because many times we need its value even though it is not the parameter of primary interest.

The t-distribution and the standard normal distribution are practically indistinguishable as the degrees of freedom increase.

There are,generally speaking,two types of statistical inference.They are:

We can form a confidence interval for the population total T by finding a confidence interval for the population mean μ\muμ in the usual way,and then multiplying the lower and upper limits the confidence interval by the population size N.

If two random samples of size 40 each are selected independently from two populations whose variances are 35 and 45,then the standard error of the sampling distribution of the sample mean difference, x1−x2x _ { 1 } - x _ { 2 }x1​−x2​ ,equals 1.4142.

For a given confidence level,the procedure for controlling interval length usually begins with the specification of

If two random samples of sizes 30 and 35 are selected independently from two populations whose means are 85 and 90,then the mean of the sampling distribution of the sample mean difference, x1−x2x _ { 1 } - x _ { 2 }x1​−x2​ ,equals 5.

A 90% confidence interval estimate for a population mean μ\muμ is determined to be 72.8 to 79.6.If the confidence level is reduced to 80%,the confidence interval for μ\muμ becomes narrower.

The interval estimate 18.5 ±\pm± 2.5 was developed for a population mean when the sample standard deviation s was 7.5.Had s equaled 15,the interval estimate would be 37 ±\pm± 5.0.

The mean of the sampling distribution of the sample proportion p^\hat { p }p^​ ,when the sample size n = 100 and the population proportion p = 0.15,is 15.0.

The lower limit of the 95% confidence interval for the population proportion p,given that n = 300;and p^\hat { p }p^​ = 0.10 is 0.1339.

If we cannot make the strong assumption that the variances of two samples are equal,then we must use the pooled standard deviation in calculating the standard error of a difference between the means.

The approximate standard error of the point estimate of the population total is Ns/nN s / \sqrt { n }Ns/n​ .

Introduction to Data Analysis and Decision Making

Describing the Distribution of a Single Variable

Finding Relationships Among Variables

Probability and Probability Distributions

Normal, Binomial, Poisson, and Exponential Distributions

Decision Making Under Uncertainty

Sampling and Sampling Distributions

Hypothesis Testing

Regression Analysis: Estimating Relationships

Regression Analysis: Statistical Inference

Time Series Analysis and Forecasting

Introduction to Optimization Modeling

Optimization Models

Introduction to Simulation Modeling

Simulation Models

Data Mining

Importing Data Into Excel

Analysis of Variance and Experimental Design

Statistical Process Control

Filters

The upper limit of the 90% confidence interval for the population proportion p,given that n = 100;and $\hat { P }$ = 0.20 is 0.2658.

A parameter such as $\sigma$ Is sometimes referred to as a ________ parameter,because many times we need its value even though it is not the parameter of primary interest.

We can form a confidence interval for the population total T by finding a confidence interval for the population mean $\mu$ in the usual way,and then multiplying the lower and upper limits the confidence interval by the population size N.

If two random samples of size 40 each are selected independently from two populations whose variances are 35 and 45,then the standard error of the sampling distribution of the sample mean difference, $x _ { 1 } - x _ { 2 }$ ,equals 1.4142.

If two random samples of sizes 30 and 35 are selected independently from two populations whose means are 85 and 90,then the mean of the sampling distribution of the sample mean difference, $x _ { 1 } - x _ { 2 }$ ,equals 5.

A 90% confidence interval estimate for a population mean $\mu$ is determined to be 72.8 to 79.6.If the confidence level is reduced to 80%,the confidence interval for $\mu$ becomes narrower.

The interval estimate 18.5 $\pm$ 2.5 was developed for a population mean when the sample standard deviation s was 7.5.Had s equaled 15,the interval estimate would be 37 $\pm$ 5.0.

The mean of the sampling distribution of the sample proportion $\hat { p }$ ,when the sample size n = 100 and the population proportion p = 0.15,is 15.0.

The lower limit of the 95% confidence interval for the population proportion p,given that n = 300;and $\hat { p }$ = 0.10 is 0.1339.

The approximate standard error of the point estimate of the population total is $N s / \sqrt { n }$ .