Question 1

The value added and subtracted from a point estimate in order to develop an interval estimate of the population parameter is known as the

Accepted Answer

A) confidence level 
B) margin of error 
C) parameter estimate 
D) interval estimate 
A) confidence level 
B) margin of error 
C) parameter estimate 
D) interval estimate

Question 2

You are given the following information obtained from a random sample of 5 observations taken from a large population. 32 34 32 30 32
Construct a 95% confidence interval for the mean of the population, assuming the population has a normal distribution.

Accepted Answer

The answer of You are given the following information obtained...

Question 3

In a random sample of 400 residents of Chattanooga, 320 residents indicated that they voted for the Democratic candidate in the last presidential election. Develop a 95% confidence interval estimate for the proportion of all Chattanooga residents who voted for the Democratic candidate.

Accepted Answer

The answer of In a random sample of 400 residents...

Question 4

The following random sample from a population whose values were normally distributed was collected.10 12 18 16
The 80% confidence interval for $\mu$is

Accepted Answer

A) 12.054 to 15.946 
B) 10.108 to 17.892 
C) 10.321 to 17.679 
D) 11.009 to 16.991 
A) 12.054 to 15.946 
B) 10.108 to 17.892 
C) 10.321 to 17.679 
D) 11.009 to 16.991

Question 5

The Highway Safety Department wants to study the driving habits of individuals. A sample of 81 cars traveling on the highway revealed an average speed of 67 miles per hour with a standard deviation of 9 miles per hour.
a.Compute the standard error of the mean.
b.Determine a 99% confidence interval estimate for the speed of all cars.

Accepted Answer

a. @#IMG-DLM& = 1
b.

Question 6

If an interval estimate is said to be constructed at the 90% confidence level, the confidence coefficient would be

Accepted Answer

A) 0.1 
B) 0.95 
C) 0.9 
D) 0.05 
A) 0.1 
B) 0.95 
C) 0.9 
D) 0.05

Question 7

A sample of 225 elements from a population with a standard deviation of 75 is selected. The sample mean is 180. The 95% confidence interval for $\mu$ is

Accepted Answer

A) 105.0 to 225.0 
B) 175.0 to 185.0 
C) 100.0 to 200.0 
D) 170.2 to 189.8 
A) 105.0 to 225.0 
B) 175.0 to 185.0 
C) 100.0 to 200.0 
D) 170.2 to 189.8

Question 8

In order to estimate the proportion of individuals who read at least one book per month, a random sample of individuals was selected and they were asked whether or not they read at least one book per month. Their responses are shown below.   Develop a 95% confidence interval for the proportion of people in the population who read at least one book per month.

Accepted Answer

0.786 to 0

Question 9

A local university administers a comprehensive examination to the candidates for B.S. degrees in Business Administration. Five examinations are selected at random and scored. The scores are shown below.   
a.Compute the mean and the standard deviation of the sample.
b.Compute the margin of error at 95% confidence.
c.Develop a 95% confidence interval estimate for the mean of the population. Assume the population is normally distributed.

Accepted Answer

a.Mean = 80, S = 11.

Question 10

For the interval estimation of$\mu$when $\sigma$ is known and the sample is large, the proper distribution to use is

Accepted Answer

A) the normal distribution 
B) the t distribution with n degrees of freedom 
C) the t distribution with n + 1 degrees of freedom 
D) the t distribution with n + 2 degrees of freedom 
A) the normal distribution 
B) the t distribution with n degrees of freedom 
C) the t distribution with n + 1 degrees of freedom 
D) the t distribution with n + 2 degrees of freedom

Question 11

In developing an interval estimate, if the population standard deviation is unknown

Accepted Answer

A) it is impossible to develop an interval estimate 
B) the standard deviation is arrived at using the range 
C) the sample standard deviation can be used 
D) it is assumed that the population standard deviation is 1 
A) it is impossible to develop an interval estimate 
B) the standard deviation is arrived at using the range 
C) the sample standard deviation can be used 
D) it is assumed that the population standard deviation is 1

Question 12

It is known that the variance of a population equals 1,936. A random sample of 121 has been taken from the population. There is a .95 probability that the sample mean will provide a margin of error of

Accepted Answer

A) 7.84 
B) 31.36 
C) 344.96 
D) 1,936 
A) 7.84 
B) 31.36 
C) 344.96 
D) 1,936

Question 13

Exhibit 8-2
A random sample of 121 automobiles traveling on an interstate showed an average speed of 65 mph. From past information, it is known that the standard deviation of the population is 22 mph.
-Refer to Exhibit 8-2. The standard error of the mean is

Accepted Answer

A) 22.00 
B) 96.60 
C) 4.24 
D) 2.00 
A) 22.00 
B) 96.60 
C) 4.24 
D) 2.00

Question 14

In order to use the normal distribution for interval estimation of $\mu$ when $\sigma$ is known and the sample is very small, the population

Accepted Answer

A) must be very large 
B) must have a normal distribution 
C) can have any distribution 
D) must have a mean of at least 1 
A) must be very large 
B) must have a normal distribution 
C) can have any distribution 
D) must have a mean of at least 1

Question 15

Two hundred students are enrolled in an Economics class. After the first examination, a random sample of 6 papers was selected. The grades were 65, 75, 89, 71, 70 and 80.
a.Determine the standard error of the mean.
b.What assumption must be made before we can determine an interval for the mean grade of all the students in the class? Explain why.
c.Assume the assumption of Part b is met. Provide a 95% confidence interval for the mean grade of all the students in the class.

Accepted Answer

a.3.474
b.Since @#LAT-DLM&is estimated f

Question 16

A local electronics firm wants to determine their average daily sales (in dollars.) A sample of the sales for 36 days revealed average sales of $139,000. Assume that the standard deviation of the population is known to be $12,000.
a.Provide a 95% confidence interval estimate for the average daily sales.
b.Provide a 97% confidence interval estimate for the average daily sales.

Accepted Answer

a.$135,080

Question 17

As the sample size increases, the margin of error

Accepted Answer

A) increases 
B) decreases 
C) stays the same 
D) increases or decreases depending on the size of the mean 
A) increases 
B) decreases 
C) stays the same 
D) increases or decreases depending on the size of the mean

Question 18

Exhibit 8-2
A random sample of 121 automobiles traveling on an interstate showed an average speed of 65 mph. From past information, it is known that the standard deviation of the population is 22 mph.
-Refer to Exhibit 8-2. If the confidence coefficient is reduced to 0.9, the standard error of the mean

Accepted Answer

A) will increase 
B) will decrease 
C) remains unchanged 
D) becomes negative 
A) will increase 
B) will decrease 
C) remains unchanged 
D) becomes negative

Question 19

Exhibit 8-6
A sample of 75 information system managers had an average hourly income of $40.75 with a standard deviation of $7.00.
-Refer to Exhibit 8-6. The value of the margin of error at 95% confidence is

Accepted Answer

A) 80.83 
B) 7 
C) 0.8083 
D) 1.611 
A) 80.83 
B) 7 
C) 0.8083 
D) 1.611

Question 20

A random sample of 49 statistics examinations was taken. The average score, in the sample, was 84 with a variance of 12.25. The 95% confidence interval for the average examination score of the population of the examinations is

Accepted Answer

A) 76.00 to 84.00 
B) 77.40 to 86.60 
C) 83.00 to 85.00 
D) 68.00 to 100.00 
A) 76.00 to 84.00 
B) 77.40 to 86.60 
C) 83.00 to 85.00 
D) 68.00 to 100.00

The value added and subtracted from a point estimate in order to develop an interval estimate of the population parameter is known as the

You are given the following information obtained from a random sample of 5 observations taken from a large population. 32 34 32 30 32 Construct a 95% confidence interval for the mean of the population, assuming the population has a normal distribution.

In a random sample of 400 residents of Chattanooga, 320 residents indicated that they voted for the Democratic candidate in the last presidential election. Develop a 95% confidence interval estimate for the proportion of all Chattanooga residents who voted for the Democratic candidate.

The following random sample from a population whose values were normally distributed was collected.10 12 18 16 The 80% confidence interval for $\mu$ is

If an interval estimate is said to be constructed at the 90% confidence level, the confidence coefficient would be

A sample of 225 elements from a population with a standard deviation of 75 is selected. The sample mean is 180. The 95% confidence interval for $\mu$ is

For the interval estimation of $\mu$ when $\sigma$ is known and the sample is large, the proper distribution to use is

In developing an interval estimate, if the population standard deviation is unknown

It is known that the variance of a population equals 1,936. A random sample of 121 has been taken from the population. There is a .95 probability that the sample mean will provide a margin of error of

Exhibit 8-2 A random sample of 121 automobiles traveling on an interstate showed an average speed of 65 mph. From past information, it is known that the standard deviation of the population is 22 mph. -Refer to Exhibit 8-2. The standard error of the mean is

In order to use the normal distribution for interval estimation of $\mu$ when $\sigma$ is known and the sample is very small, the population

As the sample size increases, the margin of error

Exhibit 8-6 A sample of 75 information system managers had an average hourly income of $40.75 with a standard deviation of $7.00. -Refer to Exhibit 8-6. The value of the margin of error at 95% confidence is

A random sample of 49 statistics examinations was taken. The average score, in the sample, was 84 with a variance of 12.25. The 95% confidence interval for the average examination score of the population of the examinations is

Data and Statistics

Descriptive Statistics: Tabular and Graphical Displays

Descriptive Statistics: Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Continuous Probability Distributions

Sampling and Sampling Distributions

Hypothesis Tests

Inference About Means and Proportions With Two Populations

Inferences About Population Variances

Comparing Multiple Proportions, Test of Independence and Goodness of Fit

Experimental Design and Analysis of Variance

Simple Linear Regression

Multiple Regression

Regression Analysis: Model Building

Time Series Analysis and Forecasting

Nonparametric Methods

Statistical Methods for Quality Control

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Exam 8: Interval Estimation

The value added and subtracted from a point estimate in order to develop an interval estimate of the population parameter is known as the

You are given the following information obtained from a random sample of 5 observations taken from a large population. 32 34 32 30 32 Construct a 95% confidence interval for the mean of the population, assuming the population has a normal distribution.

In a random sample of 400 residents of Chattanooga, 320 residents indicated that they voted for the Democratic candidate in the last presidential election. Develop a 95% confidence interval estimate for the proportion of all Chattanooga residents who voted for the Democratic candidate.

The following random sample from a population whose values were normally distributed was collected.10 12 18 16 The 80% confidence interval for μ\muμ is

If an interval estimate is said to be constructed at the 90% confidence level, the confidence coefficient would be

A sample of 225 elements from a population with a standard deviation of 75 is selected. The sample mean is 180. The 95% confidence interval for μ\muμ is

For the interval estimation of μ\muμ when σ\sigmaσ is known and the sample is large, the proper distribution to use is

In developing an interval estimate, if the population standard deviation is unknown

It is known that the variance of a population equals 1,936. A random sample of 121 has been taken from the population. There is a .95 probability that the sample mean will provide a margin of error of

Exhibit 8-2 A random sample of 121 automobiles traveling on an interstate showed an average speed of 65 mph. From past information, it is known that the standard deviation of the population is 22 mph. -Refer to Exhibit 8-2. The standard error of the mean is

In order to use the normal distribution for interval estimation of μ\muμ when σ\sigmaσ is known and the sample is very small, the population

As the sample size increases, the margin of error

Exhibit 8-6 A sample of 75 information system managers had an average hourly income of $40.75 with a standard deviation of $7.00. -Refer to Exhibit 8-6. The value of the margin of error at 95% confidence is

A random sample of 49 statistics examinations was taken. The average score, in the sample, was 84 with a variance of 12.25. The 95% confidence interval for the average examination score of the population of the examinations is

Data and Statistics

Descriptive Statistics: Tabular and Graphical Displays

Descriptive Statistics: Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Continuous Probability Distributions

Sampling and Sampling Distributions

Hypothesis Tests

Inference About Means and Proportions With Two Populations

Inferences About Population Variances

Comparing Multiple Proportions, Test of Independence and Goodness of Fit

Experimental Design and Analysis of Variance

Simple Linear Regression

Multiple Regression

Regression Analysis: Model Building

Time Series Analysis and Forecasting

Nonparametric Methods

Statistical Methods for Quality Control

Index Numbers

Decision Analysis on Website

Sample Survey on Website

Filters

The following random sample from a population whose values were normally distributed was collected.10 12 18 16 The 80% confidence interval for $\mu$ is

A sample of 225 elements from a population with a standard deviation of 75 is selected. The sample mean is 180. The 95% confidence interval for $\mu$ is

For the interval estimation of $\mu$ when $\sigma$ is known and the sample is large, the proper distribution to use is

In order to use the normal distribution for interval estimation of $\mu$ when $\sigma$ is known and the sample is very small, the population