Question 1

As n gets ____________________, the shape of the sampling distribution of $\bar { X }$ becomes increasingly bell shaped.

Accepted Answer

The answer of As n gets ____________________, the shape of...

Question 2

If all possible samples of size n are drawn from an infinite population with standard deviation 8, then the standard error of the sample mean equals 1.0 if the sample size is 64.

Accepted Answer

A) True 
 B)False

Question 3

NARRBEGIN: Average Annual Revenue
Average Annual Revenue
Suppose that the average annual revenue of a small business is $150,000 with a standard deviation of $40,000. Assume that the revenue distribution is normal.NARREND
-{Average Annual Revenue Narrative} What is the probability that one business selected at random makes less than $120,000?

Accepted Answer

The answer of NARRBEGIN: Average Annual Revenue
Average Annual Revenue
Suppose that...

Question 4

NARRBEGIN: Average Annual Revenue
Average Annual Revenue
Suppose that the average annual revenue of a small business is $150,000 with a standard deviation of $40,000. Assume that the revenue distribution is normal.NARREND
-{Average Annual Revenue Narrative} Could you have used a normal distribution to find an (approximate) probability for the average of 4 revenues if the population of revenues did not have a normal distribution?

Accepted Answer

No, because the samp

Question 5

If two random samples of sizes n1 and n2 are selected independently from two non-normally distributed populations, then the sampling distribution of the sample mean difference, $\bar { X } _ { 1 } - \bar { X } _ { 2 }$ , is

Accepted Answer

A) always non-normal 
B) always normal 
C) approximately normal only if n1 and n2 are both larger than or equal to 30 
D) approximately normal regardless of n1 and n2 
A) always non-normal 
B) always normal 
C) approximately normal only if n1 and n2 are both larger than or equal to 30 
D) approximately normal regardless of n1 and n2

Question 6

Consider an infinite population with a mean of 100 and a standard deviation of 20. A random sample of size 64 is taken from this population. The standard deviation of the sample mean equals 2.50.

Accepted Answer

A) True 
 B)False

Question 7

When a great many simple random samples of size n are drawn from a population that is normally distributed, the sampling distribution of the sample mean is normal regardless of the sample size n.

Accepted Answer

A) True 
 B)False

Question 8

A sample of size 200 is taken at random from an infinite population. Given that the population proportion is 0.60, the probability that the sample proportion is less than 0.58 is

Accepted Answer

A) 0.281 
B) 0.719 
C) 0.580 
D) 0.762 
A) 0.281 
B) 0.719 
C) 0.580 
D) 0.762

Question 9

Given an infinite population with a mean of 75 and a standard deviation of 12, the probability that the mean of a sample of 36 observations, taken at random from this population, is less than 78 is:

Accepted Answer

A) 0.9332 
B) 0.5987 
C) 1.5000 
D) None of these choices. 
A) 0.9332 
B) 0.5987 
C) 1.5000 
D) None of these choices.

Question 10

The standard error of the mean for a sample of 100 is 25. In order to cut the standard error of the mean in half (to 12.5) we must:

Accepted Answer

A) increase the sample size to 200. 
B) decrease the sample size to 50. 
C) keep the sample size at 100 and change something else. 
D) None of these choices. 
A) increase the sample size to 200. 
B) decrease the sample size to 50. 
C) keep the sample size at 100 and change something else. 
D) None of these choices.

Question 11

The estimator of the probability of success in a binomial distribution is: ____________________.

Accepted Answer

the sample

Question 12

NARRBEGIN: Average Annual Revenue
Average Annual Revenue
Suppose that the average annual revenue of a small business is $150,000 with a standard deviation of $40,000. Assume that the revenue distribution is normal.NARREND
-{Average Annual Revenue Narrative} Why are your answers to the previous two questions different?

Accepted Answer

The revenue of one business chosen from

Question 13

As the size of the sample is increased, the standard error of $\bar { X }$ decreases.

Accepted Answer

A) True 
 B)False

Question 14

The finite population correction is not needed if the population size is large relative to the sample size. As a rule of thumb, we will treat any population that is at least ____________________ times larger than the sample size as large.

Accepted Answer

The answer of The finite population correction is not needed...

Question 15

A sample of size n is selected at random from an infinite population. As n increases, which of the following statements is true?

Accepted Answer

A) The population standard deviation decreases. 
B) The standard error of the sample mean decreases. 
C) The population standard deviation increases. 
D) The standard error of the sample mean increases. 
A) The population standard deviation decreases. 
B) The standard error of the sample mean decreases. 
C) The population standard deviation increases. 
D) The standard error of the sample mean increases.

Question 16

A sampling distribution is a probability distribution for a statistic, not a parameter.

Accepted Answer

A) True 
 B)False

Question 17

As a general rule, the normal distribution is used to approximate the sampling distribution of the sample proportion only if the sample size n is greater than or equal to 30.

Accepted Answer

A) True 
 B)False

Question 18

NARRBEGIN: Retirees
Retirees
A sample of 50 retirees is drawn at random from a normal population whose mean age and standard deviation are 75 and 6 years, respectively.NARREND
-(Retirees Narrative} Describe the shape of the sampling distribution of the sample mean in this case.

Accepted Answer

@#IMG-DLM& is normal because t

Question 19

In general, the binomial probability P(X $\ge$ x) is approximated by the area under the normal curve to the left of x - .5.

Accepted Answer

A) True 
 B)False

Question 20

NARRBEGIN: Barack Obama
Barack Obama
Bill Clinton, the former President of the United States, believes that the proportion of voters who will vote for Barack Obama in the year 2012 presidential elections is 0.65. A sample of 500 voters is selected at random.NARREND
-{Barack Obama Narrative} Assume that Gore is correct and p = 0.65. What is the sampling distribution of the sample proportion $\tilde{ p }$ ? Explain.

Accepted Answer

Approximately normal

As n gets ____________________, the shape of the sampling distribution of $\bar { X }$ becomes increasingly bell shaped.

If all possible samples of size n are drawn from an infinite population with standard deviation 8, then the standard error of the sample mean equals 1.0 if the sample size is 64.

If two random samples of sizes n₁ and n₂ are selected independently from two non-normally distributed populations, then the sampling distribution of the sample mean difference, $\bar { X } _ { 1 } - \bar { X } _ { 2 }$ , is

Consider an infinite population with a mean of 100 and a standard deviation of 20. A random sample of size 64 is taken from this population. The standard deviation of the sample mean equals 2.50.

When a great many simple random samples of size n are drawn from a population that is normally distributed, the sampling distribution of the sample mean is normal regardless of the sample size n.

A sample of size 200 is taken at random from an infinite population. Given that the population proportion is 0.60, the probability that the sample proportion is less than 0.58 is

Given an infinite population with a mean of 75 and a standard deviation of 12, the probability that the mean of a sample of 36 observations, taken at random from this population, is less than 78 is:

The standard error of the mean for a sample of 100 is 25. In order to cut the standard error of the mean in half (to 12.5) we must:

The estimator of the probability of success in a binomial distribution is: ____________________.

As the size of the sample is increased, the standard error of $\bar { X }$ decreases.

The finite population correction is not needed if the population size is large relative to the sample size. As a rule of thumb, we will treat any population that is at least ____________________ times larger than the sample size as large.

A sample of size n is selected at random from an infinite population. As n increases, which of the following statements is true?

A sampling distribution is a probability distribution for a statistic, not a parameter.

As a general rule, the normal distribution is used to approximate the sampling distribution of the sample proportion only if the sample size n is greater than or equal to 30.

NARRBEGIN: Retirees Retirees A sample of 50 retirees is drawn at random from a normal population whose mean age and standard deviation are 75 and 6 years, respectively.NARREND -(Retirees Narrative} Describe the shape of the sampling distribution of the sample mean in this case.

In general, the binomial probability P(X $\ge$ x) is approximated by the area under the normal curve to the left of x - .5.

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

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations

Analysis of Variance

Chi-Squared Tests Optional

Simple Linear Regression and Correlation

Multiple Regression

Filters

Exam 9: Sampling Distributions

As n gets ____________________, the shape of the sampling distribution of Xˉ\bar { X }Xˉ becomes increasingly bell shaped.

If all possible samples of size n are drawn from an infinite population with standard deviation 8, then the standard error of the sample mean equals 1.0 if the sample size is 64.

If two random samples of sizes n1 and n2 are selected independently from two non-normally distributed populations, then the sampling distribution of the sample mean difference, Xˉ1−Xˉ2\bar { X } _ { 1 } - \bar { X } _ { 2 }Xˉ1​−Xˉ2​ , is

Consider an infinite population with a mean of 100 and a standard deviation of 20. A random sample of size 64 is taken from this population. The standard deviation of the sample mean equals 2.50.

When a great many simple random samples of size n are drawn from a population that is normally distributed, the sampling distribution of the sample mean is normal regardless of the sample size n.

A sample of size 200 is taken at random from an infinite population. Given that the population proportion is 0.60, the probability that the sample proportion is less than 0.58 is

Given an infinite population with a mean of 75 and a standard deviation of 12, the probability that the mean of a sample of 36 observations, taken at random from this population, is less than 78 is:

The standard error of the mean for a sample of 100 is 25. In order to cut the standard error of the mean in half (to 12.5) we must:

The estimator of the probability of success in a binomial distribution is: ____________________.

As the size of the sample is increased, the standard error of Xˉ\bar { X }Xˉ decreases.

The finite population correction is not needed if the population size is large relative to the sample size. As a rule of thumb, we will treat any population that is at least ____________________ times larger than the sample size as large.

A sample of size n is selected at random from an infinite population. As n increases, which of the following statements is true?

A sampling distribution is a probability distribution for a statistic, not a parameter.

As a general rule, the normal distribution is used to approximate the sampling distribution of the sample proportion only if the sample size n is greater than or equal to 30.

NARRBEGIN: Retirees Retirees A sample of 50 retirees is drawn at random from a normal population whose mean age and standard deviation are 75 and 6 years, respectively.NARREND -(Retirees Narrative} Describe the shape of the sampling distribution of the sample mean in this case.

In general, the binomial probability P(X ≥\ge≥ x) is approximated by the area under the normal curve to the left of x - .5.

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

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations

Analysis of Variance

Chi-Squared Tests Optional

Simple Linear Regression and Correlation

Multiple Regression

Filters

As n gets ____________________, the shape of the sampling distribution of $\bar { X }$ becomes increasingly bell shaped.

If two random samples of sizes n₁ and n₂ are selected independently from two non-normally distributed populations, then the sampling distribution of the sample mean difference, $\bar { X } _ { 1 } - \bar { X } _ { 2 }$ , is

As the size of the sample is increased, the standard error of $\bar { X }$ decreases.

In general, the binomial probability P(X $\ge$ x) is approximated by the area under the normal curve to the left of x - .5.