Question 1

Which of the following distributions is used to determine the sampling distribution of the sample variance?

Accepted Answer

A) normal distribution 
B) binomial distribution 
C) chi-square distribution 
D) Poisson distribution 
A) normal distribution 
B) binomial distribution 
C) chi-square distribution 
D) Poisson distribution

Question 2

If a random sample of 250 observations is taken from a population whose proportion P is equal to 0.6,then the expected value of the sample proportion   
is 0.40

Accepted Answer

A) True 
 B)False

Question 3

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
The number of hours spent studying by students on Michigan State campus in the week before final exams follows a normal distribution with standard deviation 9.5 hours.A random sample of these students is taken to estimate the population mean number of hours studying.
-Without doing the calculations,state whether a larger or smaller sample would be required to guarantee that the probability that the sample mean differs from the population mean by more than 2.1 hours is less than 0.10,when compared to the sample needed to ensure that the probability that the sample mean differs from the population mean by more thatn 2.1 hours is less than 0.05.

Accepted Answer

The answer of THE NEXT QUESTIONS ARE BASED ON THE...

Question 4

In examining the invoices issued by a company,an auditor finds that the dollar amount of invoices have a mean of $1,732 and standard deviation of $298.Which pair of symmetric numbers around the mean make the statement P(a <   
< b)= 0.853 correct for a random sample of 55 invoices?

Accepted Answer

μ = 1732,σ = 298,n = 55,then σ

Question 5

Find the expected value and the standard error of the sampling distribution of   
?

Accepted Answer

E( @#IMG-DLM& 
)= 0.

Question 6

It has been estimated that 43% of all college students change their major at least once during the course of their college career.If we take a random sample of 55 college students,what is the probability that more than 40% will change their major?

Accepted Answer

n = 55,P = 0.43.Then

Question 7

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 8

The interval within which a sample mean has a high probability of occurring,given that the population mean and variance is known,is called a(n):

Accepted Answer

A) confidence interval. 
B) rejection interval. 
C) acceptance interval. 
D) decision interval. 
A) confidence interval. 
B) rejection interval. 
C) acceptance interval. 
D) decision interval.

Question 9

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
Suppose that 20% of all invoices are for amounts greater than $800.A random sample of 50 invoices is taken.
-What is the probability that at least 25% of these 50 invoices are for more than $800?

Accepted Answer

A) 0.1894 
B) 0.8106 
C) 0.3106 
D) 0.8894 
A) 0.1894 
B) 0.8106 
C) 0.3106 
D) 0.8894

Question 10

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
Times spent studying by students in the week before final exams follow a normal distribution with standard deviation 9 hours.A random sample of 5 students was taken in order to estimate the mean study time for the population of all students.
-What is the probability that the sample mean exceeds the population mean by more than 2.1 hours?

Accepted Answer

P( @#IMG-DLM& - μ > 2.10)= P(Z

Question 11

Samples of size 2 will be drawn at random from the population.Use the formulas   
and   
to calculate the mean and the standard deviation of the sampling distribution of sample means.

Accepted Answer

E( @#IMG-DLM& 
)= μ

Question 12

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
The length of time it takes to fill an order at a local sandwich shop is normally distributed with a mean of 4.1 minutes and a standard deviation of 1.3 minutes.
-What is the probability that the average waiting time for a random sample of ten customers is between 4.0 and 4.2 minutes?

Accepted Answer

P(4.0 < @#IMG-DLM& < 4.2)= P(Z

Question 13

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
Each member of a random sample of 20 business economists was asked to predict the rate of inflation for the coming year.Assume that the predictions for the whole population of business economists follow a normal distribution with standard deviation 2%.
-The probability is 0.025 that the sample standard deviation is smaller than what value?

Accepted Answer

P(s < k)= P[(n - 1)s² / σ² < (n

Question 14

Given the results for possible magnitudes of the finite population correction factor,for samples of n =15 observations from populations of N = 15,30,60,100,500,1,000,5,000,and 10,000 members,discuss the practical significance of using the finite population correction factor for samples of 20 observations from populations of different sizes.

Accepted Answer

The correction factor tends to

Question 15

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
Let the random variable X follow a normal distribution with a mean of μ and a standard deviation of σ.Let   
S1U1B11S1U1B0 be the mean of a sample of 16 observations randomly chosen from this population,and   
S1U1B12S1U1B0 be the mean of a sample of 25 observations randomly chosen from the same population.
-Evaluate the statement P   
1 2 < μ +   
)as to whether it is true or false.Please state if you are unable to determine whether the statement is true or false.Support your answer.

Accepted Answer

Both of these expressions are asking the

Question 16

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
The filling machine at a bottling plant is operating correctly when the variance of the fill amount is equal to 0.3 ounces.Assume that the fill amounts follow a normal distribution.
-The probability is 0.10 that for a sample of 30 bottles,the sample variance is less than what number?

Accepted Answer

P(s² > k)= 0.10 ⇒ P @#IMG-DLM&

Question 17

Why is the central limit theorem important in statistics?

Accepted Answer

A) Because for a large sample size n,it says the population is approximately normal. 
B) Because for any population,it says the sampling distribution of the sample mean is approximately normal,regardless of the shape of the population. 
C) Because for a large sample size n,it says the sampling distribution of the sample mean is approximately normal,regardless of the shape of the population. 
D) Because for any sample size n,it says the sampling distribution of the sample mean is approximately normal. 
A) Because for a large sample size n,it says the population is approximately normal. 
B) Because for any population,it says the sampling distribution of the sample mean is approximately normal,regardless of the shape of the population. 
C) Because for a large sample size n,it says the sampling distribution of the sample mean is approximately normal,regardless of the shape of the population. 
D) Because for any sample size n,it says the sampling distribution of the sample mean is approximately normal.

Question 18

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
Each member of a random sample of 20 business economists was asked to predict the rate of inflation for the coming year.Assume that the predictions for the whole population of business economists follow a normal distribution with standard deviation 2%.
-Find any pair of values such that the probability that the sample standard deviation lies between these values is 0.90.

Accepted Answer

P( @#IMG-DLM& 
< 10.117)= 0.05 and P( @#IMG-DLM& 
> 30.144)=

Question 19

What is an acceptance interval?

Accepted Answer

An acceptance interval is an interval wi

Question 20

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
The average checking account balance at a local bank is $1,742 with a standard deviation of $132.A random sample of 70 accounts is selected.
-What is the probability that the average balance for these accounts is less than $1,700?

Accepted Answer

μ = 1742 and σ = 132

Which of the following distributions is used to determine the sampling distribution of the sample variance?

If a random sample of 250 observations is taken from a population whose proportion P is equal to 0.6,then the expected value of the sample proportion is 0.40

In examining the invoices issued by a company,an auditor finds that the dollar amount of invoices have a mean of $1,732 and standard deviation of $298.Which pair of symmetric numbers around the mean make the statement P(a < < b)= 0.853 correct for a random sample of 55 invoices?

Find the expected value and the standard error of the sampling distribution of ?

It has been estimated that 43% of all college students change their major at least once during the course of their college career.If we take a random sample of 55 college students,what is the probability that more than 40% will change their major?

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

The interval within which a sample mean has a high probability of occurring,given that the population mean and variance is known,is called a(n):

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION: Suppose that 20% of all invoices are for amounts greater than $800.A random sample of 50 invoices is taken. -What is the probability that at least 25% of these 50 invoices are for more than $800?

Samples of size 2 will be drawn at random from the population.Use the formulas and to calculate the mean and the standard deviation of the sampling distribution of sample means.

Why is the central limit theorem important in statistics?

What is an acceptance interval?

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION: The average checking account balance at a local bank is $1,742 with a standard deviation of $132.A random sample of 70 accounts is selected. -What is the probability that the average balance for these accounts is less than $1,700?

Describing Data: Graphical

Describing Data: Numerical

Probability

Discrete Random Variables and Probability Distributions

Continuous Random Variables and Probability Distributions

Estimation: Single Population

Estimation: Additional Topics

Hypothesis Testing: Single Population

Hypothesis Testing: Additional Topics

Simple Regression

Multiple Regression

Additional Topics in Regression Analysis

Analysis of Categorical Data

Analysis of Variance

Time-Series Analysis and Forecasting

Additional Topics in Sampling

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Exam 6: Sampling and Sampling Distributions

Which of the following distributions is used to determine the sampling distribution of the sample variance?

If a random sample of 250 observations is taken from a population whose proportion P is equal to 0.6,then the expected value of the sample proportion is 0.40

In examining the invoices issued by a company,an auditor finds that the dollar amount of invoices have a mean of $1,732 and standard deviation of $298.Which pair of symmetric numbers around the mean make the statement P(a < < b)= 0.853 correct for a random sample of 55 invoices?

Find the expected value and the standard error of the sampling distribution of ?

It has been estimated that 43% of all college students change their major at least once during the course of their college career.If we take a random sample of 55 college students,what is the probability that more than 40% will change their major?

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

The interval within which a sample mean has a high probability of occurring,given that the population mean and variance is known,is called a(n):

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION: Suppose that 20% of all invoices are for amounts greater than $800.A random sample of 50 invoices is taken. -What is the probability that at least 25% of these 50 invoices are for more than $800?

Samples of size 2 will be drawn at random from the population.Use the formulas and to calculate the mean and the standard deviation of the sampling distribution of sample means.

Why is the central limit theorem important in statistics?

What is an acceptance interval?

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION: The average checking account balance at a local bank is $1,742 with a standard deviation of $132.A random sample of 70 accounts is selected. -What is the probability that the average balance for these accounts is less than $1,700?

Describing Data: Graphical

Describing Data: Numerical

Probability

Discrete Random Variables and Probability Distributions

Continuous Random Variables and Probability Distributions

Estimation: Single Population

Estimation: Additional Topics

Hypothesis Testing: Single Population

Hypothesis Testing: Additional Topics

Simple Regression

Multiple Regression

Additional Topics in Regression Analysis

Analysis of Categorical Data

Analysis of Variance

Time-Series Analysis and Forecasting

Additional Topics in Sampling

Filters