Question 1

Given that Z is a standard normal random variable, the area to the left of a value z is expressed as

Accepted Answer

A)  P(Z $\ge$ z) 
B)  P(Z $\le$ z) 
C)  P(0 $\le$Z $\le$ z) 
D)  P(Z $\ge$ -z) 
A)  P(Z $\ge$ z) 
B)  P(Z $\le$ z) 
C)  P(0 $\le$Z $\le$ z) 
D)  P(Z $\ge$ -z)

Question 2

The variance of a $\chi$2 distribution is twice the value of its mean.

Accepted Answer

A) True 
 B)False

Question 3

The Student t distribution:

Accepted Answer

A)  is symmetrical. 
B)  approaches the normal distribution as the degrees of freedom increase. 
C)  has more area in the tails than the standard normal distribution does. 
D)  All of these choices are true. 
A)  is symmetrical. 
B)  approaches the normal distribution as the degrees of freedom increase. 
C)  has more area in the tails than the standard normal distribution does. 
D)  All of these choices are true.

Question 4

P(Z > 1.9) = ____________________ P(Z < 1.9).

Accepted Answer

The answer of P(Z > 1.9) = ____________________ P(Z <...

Question 5

Which of the following statements is false?

Accepted Answer

A)  The chi-squared distribution is positively skewed. 
B)  All the values of the chi-squared distribution are non-negative. 
C)  The shape of the chi-squared distribution depends on its degrees of freedom. 
D)  All of these choices are true. 
A)  The chi-squared distribution is positively skewed. 
B)  All the values of the chi-squared distribution are non-negative. 
C)  The shape of the chi-squared distribution depends on its degrees of freedom. 
D)  All of these choices are true.

Question 6

Probability for continuous random variables is found by finding the ____________________ under a curve.

Accepted Answer

The answer of Probability for continuous random variables is found...

Question 7

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 8

What number corresponds to F0.95,4,8?

Accepted Answer

A)  6.040 
B)  3.840 
C)  0.260 
D)  0.166 
A)  6.040 
B)  3.840 
C)  0.260 
D)  0.166

Question 9

We distinguish between discrete and continuous random variables by noting whether the number of possible values is countable or uncountable.

Accepted Answer

A) True 
 B)False

Question 10

Checking Accounts: A bank has determined that the monthly balances of the checking accounts of its customers are normally distributed with an average balance of $1,200 and a standard deviation of $250.
-What proportion of customers have monthly balances more than $1,125?

Accepted Answer

The answer of Checking Accounts: A bank has determined that...

Question 11

A normal distribution is symmetric; therefore the probability of being below the mean is 0.50 and the probability of being above the mean is 0.50.

Accepted Answer

A) True 
 B)False

Question 12

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 13

P(1 < Z < 2) = P(Z < 2) - ____________________.

Accepted Answer

The answer of P(1 < Z < 2) = P(Z...

Question 14

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 15

The variance of a Student t random variable with v degrees of freedom (v > 2) is always greater than 1.

Accepted Answer

A) True 
 B)False

Question 16

Checking Accounts: A bank has determined that the monthly balances of the checking accounts of its customers are normally distributed with an average balance of $1,200 and a standard deviation of $250.
-What proportion of customers have monthly balances between $950 and $1,075?

Accepted Answer

The answer of Checking Accounts: A bank has determined that...

Question 17

To be a legitimate probability density function, all possible values of f(x) must be non-negative.

Accepted Answer

A) True 
 B)False

Question 18

The mean and variance of a X2 distribution approach ____________________ as the degrees of freedom increase.

Accepted Answer

Question 19

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 20

A random variable X is standardized by subtracting the mean and dividing by the variance.

Accepted Answer

A) True 
 B)False

Given that Z is a standard normal random variable, the area to the left of a value z is expressed as

The variance of a $\chi$ ² distribution is twice the value of its mean.

The Student t distribution:

P(Z > 1.9) = ____________________ P(Z < 1.9).

Which of the following statements is false?

Probability for continuous random variables is found by finding the ____________________ under a curve.

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_0.95,4,8?

We distinguish between discrete and continuous random variables by noting whether the number of possible values is countable or uncountable.

Checking Accounts: A bank has determined that the monthly balances of the checking accounts of its customers are normally distributed with an average balance of $1,200 and a standard deviation of $250. -What proportion of customers have monthly balances more than $1,125?

A normal distribution is symmetric; therefore the probability of being below the mean is 0.50 and the probability of being above the mean is 0.50.

In its standardized form, the normal distribution:

P(1 < Z < 2) = P(Z < 2) - ____________________.

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

The variance of a Student t random variable with v degrees of freedom (v > 2) is always greater than 1.

Checking Accounts: A bank has determined that the monthly balances of the checking accounts of its customers are normally distributed with an average balance of $1,200 and a standard deviation of $250. -What proportion of customers have monthly balances between $950 and $1,075?

To be a legitimate probability density function, all possible values of f(x) must be non-negative.

The mean and variance of a X² distribution approach ____________________ as the degrees of freedom increase.

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

A random variable X is standardized by subtracting the mean and dividing by the variance.

What Is Statistics

Graphical and Tabular Descriptive Techniques

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations, Part 1

Inference About Comparing Two Populations, Part 2

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlation

Multiple Regression

Review of Statistical Inference

Filters

Exam 7: Continuous Probability Distributions

Given that Z is a standard normal random variable, the area to the left of a value z is expressed as

The variance of a χ\chiχ 2 distribution is twice the value of its mean.

The Student t distribution:

P(Z > 1.9) = ____________________ P(Z < 1.9).

Which of the following statements is false?

Probability for continuous random variables is found by finding the ____________________ under a curve.

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 F0.95,4,8?

We distinguish between discrete and continuous random variables by noting whether the number of possible values is countable or uncountable.

Checking Accounts: A bank has determined that the monthly balances of the checking accounts of its customers are normally distributed with an average balance of $1,200 and a standard deviation of $250. -What proportion of customers have monthly balances more than $1,125?

A normal distribution is symmetric; therefore the probability of being below the mean is 0.50 and the probability of being above the mean is 0.50.

In its standardized form, the normal distribution:

P(1 < Z < 2) = P(Z < 2) - ____________________.

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

The variance of a Student t random variable with v degrees of freedom (v > 2) is always greater than 1.

Checking Accounts: A bank has determined that the monthly balances of the checking accounts of its customers are normally distributed with an average balance of $1,200 and a standard deviation of $250. -What proportion of customers have monthly balances between $950 and $1,075?

To be a legitimate probability density function, all possible values of f(x) must be non-negative.

The mean and variance of a X2 distribution approach ____________________ as the degrees of freedom increase.

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

A random variable X is standardized by subtracting the mean and dividing by the variance.

What Is Statistics

Graphical and Tabular Descriptive Techniques

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations, Part 1

Inference About Comparing Two Populations, Part 2

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlation

Multiple Regression

Review of Statistical Inference

Filters

The variance of a $\chi$ ² distribution is twice the value of its mean.

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_0.95,4,8?

The mean and variance of a X² distribution approach ____________________ as the degrees of freedom increase.

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