Question 1

In its standardized form,the normal distribution:

Accepted Answer

A)  has a mean of 0 and a standard deviation of 1. 
B)  has a mean of 1 and a variance of 0. 
C)  has an area equal to 0.5. 
D)  cannot be used to approximate discrete probability distributions. 
A)  has a mean of 0 and a standard deviation of 1. 
B)  has a mean of 1 and a variance of 0. 
C)  has an area equal to 0.5. 
D)  cannot be used to approximate discrete probability distributions.

Question 2

If the random variable X is exponentially distributed with parameter $\lambda$ = 0.05,then the variance of X,$\sigma$2 = V(X)= 20.

Accepted Answer

A) True 
 B)False

Question 3

Given that Z is a standard normal random variable,a negative value of Z indicates that the standard deviation of Z is negative.

Accepted Answer

A) True 
 B)False

Question 4

The probability density function of a uniform random variable on the interval [0,5] must be ____________________ for 0 $\le$ x $\le$ 5.

Accepted Answer

The answer of The probability density function of a uniform...

Question 5

What number corresponds to F.025,3,5?

Accepted Answer

A)  14.88 
B)  7.76 
C)  12.06 
D)  5.41 
A)  14.88 
B)  7.76 
C)  12.06 
D)  5.41

Question 6

The number of parameters for an F distribution is:

Accepted Answer

A)  1 
B)  2 
C)  0 
D)  None of these choices. 
A)  1 
B)  2 
C)  0 
D)  None of these choices.

Question 7

Truck Salesman
A used truck salesman in a small town states that,on the average,it takes him 5 days to sell a truck.Assume that the probability distribution of the length of time between sales is exponentially distributed.
-{Truck Salesman Narrative} What is the probability that he will have to wait at least 8 days before making another sale?

Accepted Answer

0.2019 (No

Question 8

Which of the following does not represent a continuous uniform random variable?

Accepted Answer

A)  f(x)= 1/2 for x between -1 and 1,inclusive. 
B)  f(x)= 10 for x between 0 and 1/10,inclusive. 
C)  f(x)= 1/3 for x = 4,5,6. 
D)  None of these choices represents a continuous uniform random variable. 
A)  f(x)= 1/2 for x between -1 and 1,inclusive. 
B)  f(x)= 10 for x between 0 and 1/10,inclusive. 
C)  f(x)= 1/3 for x = 4,5,6. 
D)  None of these choices represents a continuous uniform random variable.

Question 9

Given that Z is a standard normal random variable,a negative value (z)on its distribution would indicate:

Accepted Answer

A)  z is to the left of the mean. 
B)  the standard deviation of this Z distribution is negative. 
C)  the area between zero and the value z is negative. 
D)  None of these choices. 
A)  z is to the left of the mean. 
B)  the standard deviation of this Z distribution is negative. 
C)  the area between zero and the value z is negative. 
D)  None of these choices.

Question 10

Which of the following is always true for all probability density functions of continuous random variables?

Accepted Answer

A)  The probability at any single point is zero. 
B)  They contain an uncountable number of possible values. 
C)  The total area under the density function f(x)equals 1. 
D)  All of these choices are true. 
A)  The probability at any single point is zero. 
B)  They contain an uncountable number of possible values. 
C)  The total area under the density function f(x)equals 1. 
D)  All of these choices are true.

Question 11

Phone Orders
The L.L.Bean catalog department that receives the majority of its orders by telephone conducted a study to determine how long customers were willing to wait on hold before ordering a product.The length of time was found to be a random variable best approximated by an exponential distribution with a mean equal to 3 minutes.
-{Phone Orders Narrative} What is the probability that a randomly selected caller is placed on hold for 3 to 6 minutes?

Accepted Answer

P(3 < X < 6)= e^-

Question 12

The Student t distribution looks similar in shape to a standard normal distribution,except it is not as widely spread.

Accepted Answer

A) True 
 B)False

Question 13

Electronics Test
The time it takes a student to finish a electronics test has a uniform distribution between 50 and 70 minutes.
-{Electronics Test Narrative} What is the median amount of time it takes a student to finish the test?

Accepted Answer

The answer of Electronics Test
The time it takes a student...

Question 14

P(Z < 3.00)is approximately ____________________.

Accepted Answer

The answer of P(Z < 3.00)is approximately ____________________....

Question 15

The expected value of the Student t distribution is zero.

Accepted Answer

A) True 
 B)False

Question 16

The value of a chi-squared distribution with 8 degrees of freedom such that the area to its left is 0.95 is 2.73.

Accepted Answer

A) True 
 B)False

Question 17

If the random variable X is exponentially distributed with parameter $\lambda$= 5,then the variance of X,$\sigma$2 = V(X)= 0.04.

Accepted Answer

A) True 
 B)False

Question 18

What proportion of the data from a normal distribution is within two standard deviations from the mean?

Accepted Answer

A)  0.3413 
B)  0.4772 
C)  0.6826 
D)  0.9544 
A)  0.3413 
B)  0.4772 
C)  0.6826 
D)  0.9544

Question 19

To find the probability for a uniform random variable you take the ____________________ times the ____________________ of its corresponding rectangle.

Accepted Answer

base;heigh

Question 20

A probability density function shows the probability for each value of X.

Accepted Answer

A) True 
 B)False

Exam 8: Continuous Probability Distributions

In its standardized form,the normal distribution:

If the random variable X is exponentially distributed with parameter λ\lambdaλ = 0.05,then the variance of X, σ\sigmaσ 2 = V(X)= 20.

Given that Z is a standard normal random variable,a negative value of Z indicates that the standard deviation of Z is negative.

The probability density function of a uniform random variable on the interval [0,5] must be ____________________ for 0 ≤\le≤ x ≤\le≤ 5.

What number corresponds to F.025,3,5?

The number of parameters for an F distribution is:

Which of the following does not represent a continuous uniform random variable?

Given that Z is a standard normal random variable,a negative value (z)on its distribution would indicate:

Which of the following is always true for all probability density functions of continuous random variables?

The Student t distribution looks similar in shape to a standard normal distribution,except it is not as widely spread.

Electronics Test The time it takes a student to finish a electronics test has a uniform distribution between 50 and 70 minutes. -{Electronics Test Narrative} What is the median amount of time it takes a student to finish the test?

P(Z < 3.00)is approximately ____________________.

The expected value of the Student t distribution is zero.

The value of a chi-squared distribution with 8 degrees of freedom such that the area to its left is 0.95 is 2.73.

If the random variable X is exponentially distributed with parameter λ\lambdaλ = 5,then the variance of X, σ\sigmaσ 2 = V(X)= 0.04.

What proportion of the data from a normal distribution is within two standard deviations from the mean?

To find the probability for a uniform random variable you take the ____________________ times the ____________________ of its corresponding rectangle.

A probability density function shows the probability for each value of X.

What Is Statistics

Graphical Descriptive Techniques I

Graphical Descriptive Techniques II

A: Numerical Descriptive Techniques

B: Numerical Descriptive Techniques

C: Numerical Descriptive Techniques

Data Collection and Sampling

Probability

A: Random Variables and Discrete Probability Distributions

B: Random Variables and Discrete 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

A: Simple Linear Regression and Correlation

B: Simple Linear Regression and Correlation

Multiple Regression

Model Building

Nonparametric Statistics

Time-Series Analysis and Forecasting

Statistical Process Control

Decision Analysis

Conclusion

Filters

If the random variable X is exponentially distributed with parameter $\lambda$ = 0.05,then the variance of X, $\sigma$ ² = V(X)= 20.

The probability density function of a uniform random variable on the interval [0,5] must be ____________________ for 0 $\le$ x $\le$ 5.

What number corresponds to F_.025,3,5?

If the random variable X is exponentially distributed with parameter $\lambda$ = 5,then the variance of X, $\sigma$ ² = V(X)= 0.04.

To find the probability for a uniform random variable you take the times the of its corresponding rectangle.