Review: Normal Dist

Question 1

The Empirical Rule of probability can be applied to the uniform probability distribution
T/F

Answer 1

FA

Question 2

Areas within a continuous probability distribution represent probabilities.
T/F

Answer 2

TR

Question 3

The total area within a continuous probability distribution is equal to 100.
T/F

Answer 3

FAL

Question 4

The total area within any continuous probability distribution is equal to 1.00
T/F

Answer 4

TR

Question 5

For any continuous probability distribution, the probability, P(x), of any value of the random variable, X, can be computed.
T/F

Answer 5

FA

Question 6

For any discrete probability distribution, the probability, P(x), of any value of the random variable, X, can be computed.
T/F

Answer 6

TR

Question 7

The uniform probability distribution’s standard deviation is proportional to the distribution’s range.
T/F

Answer 7

TR

Question 8

For any uniform probability distribution, the mean and standard deviation can be computed by knowing the maximum and minimum values of the random variable.
T/F

Answer 8

T

Question 9

In a uniform probability distribution, P(x) is constant between the distribution’s minimum and maximum values.
T/F

Answer 9

TR

Question 10

For a uniform probability distribution, the probability of any event is equal to 1/(b-a).
T/F

Answer 10

FA

Question 11

The uniform probability distribution is symmetric about the mode.
T/F

Answer 11

FA

Question 12

The uniform probability distribution’s shape is a rectangle.

Answer 12

TR

Question 13

The uniform probability distribution is symmetric about the mean and median.
T/F

Answer 13

T

Question 14

A continuity correction factor compensates for estimating a discrete distribution with a continuous distribution

Answer 14

TR

Question 15

When referring to the normal probability distribution, there is not just one; there is a “family” of distributions.

Answer 15

TR

Question 16

The area under the normal curve within plus and minus one standard deviation of the mean is about 68.26%.

Answer 16

TR

Question 17

The total area under the normal curve is 100%.

Answer 17

TR

Question 18

The shape of any uniform probability distribution is 
A)  Negatively skewed 
B)  Positively skewed 
C)  Rectangular 
D)  Bell shaped

Answer 18

C

Question 19

The upper and lower limits of a uniform probability distribution are
A) positive and negative infinity
B) plus and minus three standard deviations.
C) 0 and 1
D) the maximum and minimum values of the random variable.

Answer 19

D

Question 20

When using the binomial distribution to approximate a normal distribution, what is the value of the continuity correction factor? 
A)  1.00 
B)  0.50 
C)  100 
D)  1.96

Answer 20

B

Question 21

What is an important similarity between the uniform and normal probability distributions?
A) The mean, median and mode are all equal.
B) The mean and median are equal
C) They are negatively skewed
D) About 68% of all observations are within one standard deviation of the mean.

Answer 21

B

Question 22

Which of the following is NOT true regarding the normal distribution?
A) Mean, median and mode are all equal
B) It has a single peak
C) It is symmetrical
D) The points of the curve meet the X-axis at z = –3 and z = 3

Answer 22

D

Question 23

For the normal distribution, the mean plus and minus 1.96 standard deviations will include about what percent of the observations? 
A)  50% 
B)  99.7% 
C)  95% 
D)  68%

Answer 23

C

Question 24

Which of the following is NOT a characteristic of the normal probability distribution? 
A)  Positively-skewed 
B)  Bell-shaped 
C)  Symmetrical 
D)  Asymptotic

Answer 24

A

Question 25

Which of the following is true in a normal distribution? A) Mean equals the mode and the median B) Mode equals the median C) Mean divides the distribution into two equal parts D) All of the above are correct

Answer 25

D

Question 26

Two normal distributions are compared. One has a mean of 10 and a standard deviation of 10. The second normal distribution has a mean of 10 and a standard deviation of 2. Which of the following it true? A) the locations of the distributions are different B) the distributions are from two different families C) the dispersions of the distributions are different D) the dispersions of the distributions are the same

Answer 26

C

Question 27

``` An area of a normal probability distribution represents A) a permutation B) a combination C) a likelihood D) a shaded area ```

Answer 27

C

Question 28

What is a graph of a normal probability distribution called? _________

Answer 28

normal curve

Question 29

What type of probability distribution is the normal distribution? ______________

Answer 29

Continuous

Question 30

One of the properties of the normal curve is that it gets closer to the horizontal axis, but never touches it. What is this property of the normal curve called? _________________

Answer 30

asymptotic