Question 1

In estimating the population mean with the population standard deviation unknown, if the sample size is 16, there are 8 degrees of freedom.

Accepted Answer

A) True 
 B)False

Question 2

NARRBEGIN: Hourly Fees
Hourly Fees
A random sample of 15 hourly fees for car washers (including tips) was drawn from a normal population. The sample mean and sample standard deviation were $\bar { x }$ = $14.9 and s = $6.75.NARREND
-{Hourly Fees Narrative} Can we infer at the 5% significance level that the population mean is greater than 12, assuming that you know the population standard deviation is equal to 6.75?

Accepted Answer

Rejection region: z > z_0.05 = 1.64

Question 3

In a hypothesis test for the population variance, the hypotheses are H0: $\sigma$2 = 100 vs. H1: $\sigma$2 $\neq$100. If the sample size is 15 and the test is being carried out at the 10% level of significance, the rejection region is:

Accepted Answer

A) $\chi$2 2 > 23.685. B) $\chi$2 2 > 21.064. C) $\chi$2 2 > 22.307. D) $\chi$2 2 < 24.996. A) $\chi$2 2 > 23.685. B) $\chi$2 2 > 21.064. C) $\chi$2 2 > 22.307. D) $\chi$2 2 < 24.996.

Question 4

In estimating the population mean $\mu$ when the population size N is small, the confidence interval estimator of $\mu$is $\bar { x } \pm t _ { \omega / 2 } \cdot \frac { s } { \sqrt { n } } \sqrt { \frac { N - n } { N - 1 } }$ .

Accepted Answer

A) True 
 B)False

Question 5

NARRBEGIN: Pilots' Union Contract
Pilots' Union Contract
A union composed of several thousand pilots is preparing to vote on a new contract. A random sample of 500 pilots yielded 320 who planned to vote yes. It is believed that the new contract will receive more than 60% yes votes.NARREND
-{Pilots' Union Contract Narrative} Compute the p-value for the test.

Accepted Answer

The answer of NARRBEGIN: Pilots' Union Contract
Pilots' Union Contract
A union...

Question 6

The t-distribution allows the calculation of confidence intervals for means for small samples when the population variance is not known, regardless of the shape of the distribution in the population.

Accepted Answer

A) True 
 B)False

Question 7

NARRBEGIN: Physicians
Physicians
A random sample of 200 physicians shows that there are 36 of them who make at least $400,000 a year.NARREND
-{Physicians Narrative} Can we conclude at the 1% significance level that the true proportion of physicians in the population who make at least $400,000 a year is less than 0.24?

Accepted Answer

H₀: p = 0.24, H₁: p < 0.24 Rejection regio

Question 8

If the sampled population is nonnormal, the t-test of the population mean $\mu$ is still valid, provided that the condition is not extreme.

Accepted Answer

A) True 
 B)False

Question 9

When a population is small relative to the sample size, we must incorporate the ____________________ factor in the calculation of the standard error of estimate of the mean.

Accepted Answer

finite pop

Question 10

The test statistic used to test hypotheses about the population variance has a chi-squared distribution with ____________________ degrees of freedom.

Accepted Answer

The answer of The test statistic used to test hypotheses...

Question 11

Which of the following statements is false?

Accepted Answer

A) Because there is one single way to segment a market, managers must consider several variable or characteristics that could be used to identify segments. 
B) Surveys of customers are used to gather data about various aspects of the market. 
C) Statistical techniques are applied to the survey data to define the market segments. 
D) Market segmentation separates consumers of a product into different groups in such a way that members of each group are similar to each other and there are differences between groups. 
A) Because there is one single way to segment a market, managers must consider several variable or characteristics that could be used to identify segments. 
B) Surveys of customers are used to gather data about various aspects of the market. 
C) Statistical techniques are applied to the survey data to define the market segments. 
D) Market segmentation separates consumers of a product into different groups in such a way that members of each group are similar to each other and there are differences between groups.

Question 12

As a manufacturer of guitars, a major corporation wants to estimate the proportion of guitar players who are right-handed. How many golfers must be surveyed if they want to be within 0.02, with a 95% confidence?
a.Assume that there is no prior information that could be used as an estimate of.
b.Assume that the manufacturer has an estimate offound from a previous study, which suggests that 75% of guitar players are right-handed.

Accepted Answer

a.n = 2401

Question 13

The statistic (n -1)s2 / $\sigma$2 has a chi-squared distribution with n - 1 degrees of freedom if:

Accepted Answer

A) the sample has a Student t-distribution with degrees of freedom equal to n - 1. 
B) the sample is normally distributed with variance equal to s2. 
C) the population is normally distributed with variance equal to $\sigma$2. 
D) All of these choices are true. 
A) the sample has a Student t-distribution with degrees of freedom equal to n - 1. 
B) the sample is normally distributed with variance equal to s2. 
C) the population is normally distributed with variance equal to $\sigma$2. 
D) All of these choices are true.

Question 14

The test statistic for p is approximately normal when ____________________ and ____________________ are both greater than 5.

Accepted Answer

np; n(1 -

Question 15

A condition of using the chi-squared test statistic for testing the variance is that the population random variable have a normal distribution.

Accepted Answer

A) True 
 B)False

Question 16

The sampling distribution of $\hat { p }$ is approximately normal if the sample size is more than 30.

Accepted Answer

A) True 
 B)False

Question 17

In forming a 95% confidence interval for a population mean from a sample size of 20, the number of degrees of freedom from the t-distribution equals 20.

Accepted Answer

A) True 
 B)False

Question 18

NARRBEGIN: Healthy foods
Healthy Foods
In segmenting the frozen meal market in Spain, a food manufacturer uses health and diet consciousness as the segmentation variable. Four segments are developed and coded as follows:
 1: Concermed about eating healthy faods
2: Concerned about weight
3: Concerned about health because of illnese
4: Unconcermed To distinguish between groups, surveys are conducted. On the basis of a questionnaire, people are categorized as belonging to one of these groups. A recent survey asked a random sample of 1,500 Spanish adults (20 and over) to complete the survey. Out of the 1,500 people surveyed, 360 indicated that they are concerned about eating healthy foods. The most recent information available reveals that there are 40,256,000 Spanish adults who are 20 and over.NARREND
-{Healthy Foods Narrative} Interpret the confidence interval of p.

Accepted Answer

We estimate that the proportio

Question 19

NARRBEGIN: New Mousetrap
New Mousetrap
After a financial analysis, the general manager of a large company decided that if more than 8% of potential buyers of a new mousetrap purchase that product, the company would show a profit. In a preliminary survey of 500 potential buyers, 56 people say that they will buy the mousetrap.NARREND
-{New Mousetrap Narrative} State the appropriate null and alternative hypotheses.

Accepted Answer

H₀: p = 0.0

Question 20

NARRBEGIN: Concert Tickets
Concert Tickets
A simple random sample of 100 concert tickets was drawn from a normal population. The mean and standard deviation of the sample were $120 and $25, respectively.NARREND
-{Concert Tickets Narrative} Estimate the population mean with 90% confidence.

Accepted Answer

@#IMG-DLM& . Thus, L

In estimating the population mean with the population standard deviation unknown, if the sample size is 16, there are 8 degrees of freedom.

In a hypothesis test for the population variance, the hypotheses are H₀: $\sigma$ ² = 100 vs. H₁: $\sigma$ ² $\neq$ 100. If the sample size is 15 and the test is being carried out at the 10% level of significance, the rejection region is:

In estimating the population mean $\mu$ when the population size N is small, the confidence interval estimator of $\mu$ is $\bar { x } \pm t _ { \omega / 2 } \cdot \frac { s } { \sqrt { n } } \sqrt { \frac { N - n } { N - 1 } }$ .

The t-distribution allows the calculation of confidence intervals for means for small samples when the population variance is not known, regardless of the shape of the distribution in the population.

If the sampled population is nonnormal, the t-test of the population mean $\mu$ is still valid, provided that the condition is not extreme.

When a population is small relative to the sample size, we must incorporate the ____________________ factor in the calculation of the standard error of estimate of the mean.

The test statistic used to test hypotheses about the population variance has a chi-squared distribution with ____________________ degrees of freedom.

Which of the following statements is false?

The statistic (n -1)s² / $\sigma$ ² has a chi-squared distribution with n - 1 degrees of freedom if:

The test statistic for p is approximately normal when and are both greater than 5.

A condition of using the chi-squared test statistic for testing the variance is that the population random variable have a normal distribution.

The sampling distribution of $\hat { p }$ is approximately normal if the sample size is more than 30.

In forming a 95% confidence interval for a population mean from a sample size of 20, the number of degrees of freedom from the t-distribution equals 20.

NARRBEGIN: Concert Tickets Concert Tickets A simple random sample of 100 concert tickets was drawn from a normal population. The mean and standard deviation of the sample were $120 and $25, respectively.NARREND -{Concert Tickets Narrative} Estimate the population mean with 90% confidence.

What Is Statistics

Graphical Descriptive Techniques I

Graphical Descriptive Techniques II

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About Comparing Two Populations

Analysis of Variance

Chi-Squared Tests Optional

Simple Linear Regression and Correlation

Multiple Regression

Filters

Exam 12: Inference About a Population

In estimating the population mean with the population standard deviation unknown, if the sample size is 16, there are 8 degrees of freedom.

In a hypothesis test for the population variance, the hypotheses are H0: σ\sigmaσ 2 = 100 vs. H1: σ\sigmaσ 2 ≠\neq= 100. If the sample size is 15 and the test is being carried out at the 10% level of significance, the rejection region is:

In estimating the population mean μ\muμ when the population size N is small, the confidence interval estimator of μ\muμ is xˉ±tω/2⋅snN−nN−1\bar { x } \pm t _ { \omega / 2 } \cdot \frac { s } { \sqrt { n } } \sqrt { \frac { N - n } { N - 1 } }xˉ±tω/2​⋅n​s​N−1N−n​​ .

The t-distribution allows the calculation of confidence intervals for means for small samples when the population variance is not known, regardless of the shape of the distribution in the population.

If the sampled population is nonnormal, the t-test of the population mean μ\muμ is still valid, provided that the condition is not extreme.

When a population is small relative to the sample size, we must incorporate the ____________________ factor in the calculation of the standard error of estimate of the mean.

The test statistic used to test hypotheses about the population variance has a chi-squared distribution with ____________________ degrees of freedom.

Which of the following statements is false?

The statistic (n -1)s2 / σ\sigmaσ 2 has a chi-squared distribution with n - 1 degrees of freedom if:

The test statistic for p is approximately normal when ____________________ and ____________________ are both greater than 5.

A condition of using the chi-squared test statistic for testing the variance is that the population random variable have a normal distribution.

The sampling distribution of p^\hat { p }p^​ is approximately normal if the sample size is more than 30.

In forming a 95% confidence interval for a population mean from a sample size of 20, the number of degrees of freedom from the t-distribution equals 20.

NARRBEGIN: Concert Tickets Concert Tickets A simple random sample of 100 concert tickets was drawn from a normal population. The mean and standard deviation of the sample were $120 and $25, respectively.NARREND -{Concert Tickets Narrative} Estimate the population mean with 90% confidence.

What Is Statistics

Graphical Descriptive Techniques I

Graphical Descriptive Techniques II

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About Comparing Two Populations

Analysis of Variance

Chi-Squared Tests Optional

Simple Linear Regression and Correlation

Multiple Regression

Filters

In a hypothesis test for the population variance, the hypotheses are H₀: $\sigma$ ² = 100 vs. H₁: $\sigma$ ² $\neq$ 100. If the sample size is 15 and the test is being carried out at the 10% level of significance, the rejection region is:

In estimating the population mean $\mu$ when the population size N is small, the confidence interval estimator of $\mu$ is $\bar { x } \pm t _ { \omega / 2 } \cdot \frac { s } { \sqrt { n } } \sqrt { \frac { N - n } { N - 1 } }$ .

If the sampled population is nonnormal, the t-test of the population mean $\mu$ is still valid, provided that the condition is not extreme.

The statistic (n -1)s² / $\sigma$ ² has a chi-squared distribution with n - 1 degrees of freedom if:

The test statistic for p is approximately normal when and are both greater than 5.

The sampling distribution of $\hat { p }$ is approximately normal if the sample size is more than 30.