Question 1

The number of customers making a purchase out of 30 randomly selected customers has a Poisson distribution.

Accepted Answer

A) True 
 B)False

Question 2

The ____________________ and the ____________________ both measure the relationship between two random variables X and Y.

Accepted Answer

covariance

Question 3

In a Poisson distribution, the mean and standard deviation are equal.

Accepted Answer

A) True 
 B)False

Question 4

If you add two single probability distributions together you get a bivariate distribution.

Accepted Answer

A) True 
 B)False

Question 5

In the Poisson distribution, the ____________________ is equal to the variance.

Accepted Answer

The answer of In the Poisson distribution, the ____________________ is...

Question 6

The ____________________ of a Poisson distribution is the rate at which successes occur for a given period of time or interval of space.

Accepted Answer

The answer of The ____________________ of a Poisson distribution is...

Question 7

The possible values of a Poisson random variable start at ____________________.

Accepted Answer

The answer of The possible values of a Poisson random...

Question 8

Which of the following is not a required condition for the distribution of a discrete random variable X that can assume values xi?

Accepted Answer

A)  0 $\le$ p(xi) $\le$ 1 for all xi 
B)    
C)  p(xi) > 1 for all xi 
D)  All of these choices are true. 
A)  0 $\le$ p(xi) $\le$ 1 for all xi 
B)    
C)  p(xi) > 1 for all xi 
D)  All of these choices are true.

Question 9

The Sutton police department must write, on average, 6 tickets a day to keep department revenues at budgeted levels.Suppose the number of tickets written per day follows a Poisson distribution with a mean of 6.5 tickets per day.Interpret the value of the mean.

Accepted Answer

A)  The mean has no interpretation. 
B)  The expected number of tickets written would be 6.5 per day. 
C)  Half of the days have less than 6.5 tickets written and half of the days have more than 6.5 tickets written. 
D)  The number of tickets that is written most often is 6.5 tickets per day. 
A)  The mean has no interpretation. 
B)  The expected number of tickets written would be 6.5 per day. 
C)  Half of the days have less than 6.5 tickets written and half of the days have more than 6.5 tickets written. 
D)  The number of tickets that is written most often is 6.5 tickets per day.

Question 10

If X and Y are random variables, the sum of all the conditional probabilities of X given a specific value of Y will always be:

Accepted Answer

A)  0.0 
B)  1.0 
C)  the average of the possible values of X. 
D)  the average of the possible values of Y. 
A)  0.0 
B)  1.0 
C)  the average of the possible values of X. 
D)  the average of the possible values of Y.

Question 11

For a random variable X, V(X + 3) = V(X + 6), where V refers to the variance.

Accepted Answer

A) True 
 B)False

Question 12

If X and Y are random variables with E(X) = 6 and E(Y) = 9, then E(2X + 3Y) is:

Accepted Answer

A)  39 
B)  15 
C)  27 
D)  12 
A)  39 
B)  15 
C)  27 
D)  12

Question 13

The Poisson random variable is a discrete random variable with infinitely many possible values.

Accepted Answer

A) True 
 B)False

Question 14

Golfing Store
The joint probability distribution of variables X and Y is shown in the table below, where X is the number of drivers and Y is the number of putters sold daily in a small golfing store.
  
-{Golfing Store Narrative} Are X and Y independent? Explain.

Accepted Answer

Yes, becau

Question 15

In a Poisson distribution, the:

Accepted Answer

A)  mean equals the standard deviation. 
B)  median equals the standard deviation. 
C)  mean equals the variance. 
D)  None of these choices. 
A)  mean equals the standard deviation. 
B)  median equals the standard deviation. 
C)  mean equals the variance. 
D)  None of these choices.

Question 16

The variance of a portfolio of two investments will be equal to the sum of the variances of the two investments plus twice the covariance between the investments.

Accepted Answer

A) True 
 B)False

Question 17

911 Phone Calls
911 phone calls arrive at the rate of 30 per hour at the local call center.
-{911 Phone Calls Narrative} Find the probability of receiving two calls in a five-minute interval of time.

Accepted Answer

@#LAT-DLM& = 5(30/60

Question 18

Sports Fans
Suppose that past history shows that 5% of college students are sports fans.A sample of 10 students is to be selected.
-{Sports Fans Narrative} Find the probability that exactly 1 student is a sports fan.

Accepted Answer

The answer of Sports Fans
Suppose that past history shows that...

Question 19

If the probability of success p remains constant in a binomial distribution, an increase in n will not change the mean.

Accepted Answer

A) True 
 B)False

Question 20

The variance of the sum always equals the sum of the variances.

Accepted Answer

A) True 
 B)False

The number of customers making a purchase out of 30 randomly selected customers has a Poisson distribution.

The and the both measure the relationship between two random variables X and Y.

In a Poisson distribution, the mean and standard deviation are equal.

If you add two single probability distributions together you get a bivariate distribution.

In the Poisson distribution, the ____________________ is equal to the variance.

The ____________________ of a Poisson distribution is the rate at which successes occur for a given period of time or interval of space.

The possible values of a Poisson random variable start at ____________________.

Which of the following is not a required condition for the distribution of a discrete random variable X that can assume values x_i?

The Sutton police department must write, on average, 6 tickets a day to keep department revenues at budgeted levels.Suppose the number of tickets written per day follows a Poisson distribution with a mean of 6.5 tickets per day.Interpret the value of the mean.

If X and Y are random variables, the sum of all the conditional probabilities of X given a specific value of Y will always be:

For a random variable X, V(X + 3) = V(X + 6), where V refers to the variance.

If X and Y are random variables with E(X) = 6 and E(Y) = 9, then E(2X + 3Y) is:

The Poisson random variable is a discrete random variable with infinitely many possible values.

Golfing Store The joint probability distribution of variables X and Y is shown in the table below, where X is the number of drivers and Y is the number of putters sold daily in a small golfing store. -{Golfing Store Narrative} Are X and Y independent? Explain.

In a Poisson distribution, the:

The variance of a portfolio of two investments will be equal to the sum of the variances of the two investments plus twice the covariance between the investments.

911 Phone Calls 911 phone calls arrive at the rate of 30 per hour at the local call center. -{911 Phone Calls Narrative} Find the probability of receiving two calls in a five-minute interval of time.

Sports Fans Suppose that past history shows that 5% of college students are sports fans.A sample of 10 students is to be selected. -{Sports Fans Narrative} Find the probability that exactly 1 student is a sports fan.

If the probability of success p remains constant in a binomial distribution, an increase in n will not change the mean.

The variance of the sum always equals the sum of the variances.

What Is Statistics

Graphical Descriptive Techniques I

Graphical Descriptive Techniques II

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Continuous Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlation

Multiple Regression

Filters

Exam 7: Random Variables and Discrete Probability Distributions

The number of customers making a purchase out of 30 randomly selected customers has a Poisson distribution.

The ____________________ and the ____________________ both measure the relationship between two random variables X and Y.

In a Poisson distribution, the mean and standard deviation are equal.

If you add two single probability distributions together you get a bivariate distribution.

In the Poisson distribution, the ____________________ is equal to the variance.

The ____________________ of a Poisson distribution is the rate at which successes occur for a given period of time or interval of space.

The possible values of a Poisson random variable start at ____________________.

Which of the following is not a required condition for the distribution of a discrete random variable X that can assume values xi?

The Sutton police department must write, on average, 6 tickets a day to keep department revenues at budgeted levels.Suppose the number of tickets written per day follows a Poisson distribution with a mean of 6.5 tickets per day.Interpret the value of the mean.

If X and Y are random variables, the sum of all the conditional probabilities of X given a specific value of Y will always be:

For a random variable X, V(X + 3) = V(X + 6), where V refers to the variance.

If X and Y are random variables with E(X) = 6 and E(Y) = 9, then E(2X + 3Y) is:

The Poisson random variable is a discrete random variable with infinitely many possible values.

Golfing Store The joint probability distribution of variables X and Y is shown in the table below, where X is the number of drivers and Y is the number of putters sold daily in a small golfing store. -{Golfing Store Narrative} Are X and Y independent? Explain.

In a Poisson distribution, the:

The variance of a portfolio of two investments will be equal to the sum of the variances of the two investments plus twice the covariance between the investments.

911 Phone Calls 911 phone calls arrive at the rate of 30 per hour at the local call center. -{911 Phone Calls Narrative} Find the probability of receiving two calls in a five-minute interval of time.

Sports Fans Suppose that past history shows that 5% of college students are sports fans.A sample of 10 students is to be selected. -{Sports Fans Narrative} Find the probability that exactly 1 student is a sports fan.

If the probability of success p remains constant in a binomial distribution, an increase in n will not change the mean.

The variance of the sum always equals the sum of the variances.

What Is Statistics

Graphical Descriptive Techniques I

Graphical Descriptive Techniques II

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Continuous Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlation

Multiple Regression

Filters

The and the both measure the relationship between two random variables X and Y.

Which of the following is not a required condition for the distribution of a discrete random variable X that can assume values x_i?