Question 1

The 3-sigma rule is violated when the mean, mode and median are the same value.

Accepted Answer

A) True 
 B)False

Question 2

The closer the score is to the mean, the less frequent it is in the distribution.

Accepted Answer

A) True 
 B)False

Question 3

Which of the following information is missing from non-standard scores that is present in standard scores?

Accepted Answer

A)  The range of scores from the lowest to highest. 
B)  The actual value of a measurement in nature, accounting for error. 
C)  The change in an individual's scores over time. 
D)  The location of individual scores in a set, relative to the mean

Question 4

Jessica scores the same as the mean on a test. Her z-score is zero.

Accepted Answer

A) True 
 B)False

Question 5

An individual who scores higher than the mean on a test will have a z-score that is negative.

Accepted Answer

A) True 
 B)False

Question 6

In a symmetric distribution, the probability of obtaining a z-score above 3 is exactly the same as the probability of obtaining a z-score below -3.

Accepted Answer

A) True 
 B)False

Question 7

Kristie's z-score is -2.01 on a test with a mean of 70 and standard deviation of 2. What is her raw score? Round your answer to the nearest whole number.

Accepted Answer

The answer of Kristie's z-score is -2.01 on a test...

Question 8

If you obtain an observed z-score that is larger than critical z, you should always reject the null hypothesis.

Accepted Answer

A) True 
 B)False

Question 9

Someone's z-score on a test can only be known if we know both the population mean of the test and the standard deviation.

Accepted Answer

A) True 
 B)False

Question 10

The z-test is a popular test because it is easy to calculate and does not make assumptions about the distribution of the data.

Accepted Answer

A) True 
 B)False

Question 11

$$\begin{array} { | l | l | } 
\hline \text { Length (inch) } & \text { Frequency } \
\hline 0.1 & 2 \
\hline 0.2 & 3 \
\hline 0.3 & 3 \
\hline 0.4 & 5 \
\hline 0.5 & 4 \
\hline 0.6 & 2 \
\hline 0.7 & 2 \
\hline
\end{array}$$ Adele is studying a new species of insect that emits an odor perceived to be pleasant to humans. The known population consists of 21 insects. Adele has measured the length of each one.
Adele discovers a new specimen of this insect species. It is 0.5 inches long. What is its z-score?

Accepted Answer

A)  0.50 
B)  0.61 
C)  0.71 
D)  0.80

Question 12

Last semester, Julia scored 140 on an intelligence test with a mean of 100 and standard deviation of 10. This year, she scored 100 on a different intelligence test with a mean of 60 and standard deviation of 10. Which of the following statements is true in relation to Julia's scores?

Accepted Answer

A)  Julia performed better this year. 
B)  Julia performed better last year. 
C)  Julia performed equally well in both years. 
D)  None of the above.

Question 13

A test of spatial skills has a mean of 70 and a standard deviation of 6. A different test for vocabulary knowledge has the same mean and standard deviation. Which of the following options is true?

Accepted Answer

A)  A z-score of -2 on the test of spatial skills is the same distance from the mean as a raw score of 120 on the test for vocabulary knowledge. 
B)  A z-score of -1.5 on the test of spatial skills is the same distance from the mean as a raw score of 85 on the test for vocabulary knowledge. 
C)  A raw score of 135 on the test of spatial skills is not the same distance from the mean as a z-score of 3.5 on the test for vocabulary knowledge. 
D)  A raw score of 90 on the test of spatial skills is the same distance from the mean as a z-score of 1.

Question 14

A deviation score is the numerator of the formula for calculating a z-score.

Accepted Answer

A) True 
 B)False

Question 15

$$\begin{array} { | l | l | } 
\hline \text { Length (inch) } & \text { Frequency } \
\hline 0.1 & 2 \
\hline 0.2 & 3 \
\hline 0.3 & 3 \
\hline 0.4 & 5 \
\hline 0.5 & 4 \
\hline 0.6 & 2 \
\hline 0.7 & 2 \
\hline
\end{array}$$ Adele is studying a new species of insect that emits an odor perceived to be pleasant to humans. The known population consists of 21 insects. Adele has measured the length of each one.
An insect that is 0.2 inches long would have a deviation score of:

Accepted Answer

A)  0 
B)  -0.1 
C)  0.1 
D)  -0.2 
E)  0.2

Question 16

Suzanne would like to calculate the z-score of her height relative to the height of ballerinas. She is 5'7. What other information does she need to obtain the z-score of her height?

Accepted Answer

A)  Mean height of all ballerinas in general, and the standard deviation 
B)  Mean height of ballerinas in her class, and the standard error 
C)  The most common height of ballerinas, and the standard deviation 
D)  The most common height of ballerinas, and the range

Question 17

$$\begin{array} { | l | l | } 
\hline \text { Length (inch) } & \text { Frequency } \
\hline 0.1 & 2 \
\hline 0.2 & 3 \
\hline 0.3 & 3 \
\hline 0.4 & 5 \
\hline 0.5 & 4 \
\hline 0.6 & 2 \
\hline 0.7 & 2 \
\hline
\end{array}$$ Adele is studying a new species of insect that emits an odor perceived to be pleasant to humans. The known population consists of 21 insects. Adele has measured the length of each one.
An insect in the original population is shorter than 96% of the class. How long is this particular insect?

Accepted Answer

A)  0.1 
B)  0.2 
C)  -0.2 
D)  -0

Question 18

Josh's z-score on a test is -0.5. Which of the following options must be true?

Accepted Answer

A)  Josh scored better than 65% of other test takers. 
B)  Josh scored better than 25% of other test takers. 
C)  Josh scored worse than 16% of other test takers. 
D)  Josh scored worse than 72% of other test takers.

Question 19

Lewis obtained a score of 45 on a test with a mean of 55 and a standard deviation of 10. What is the percentile of Lewis' score? Round your answer to the nearest whole number.

Accepted Answer

The answer of Lewis obtained a score of 45 on...

Question 20

A test of spatial skills has a mean of 80 and a standard deviation of 5. A newer, different test that also measures spatial skills has a mean of 100 and a standard deviation of 2. The distribution of the older test is ________________ than the distribution of the newer test.

Accepted Answer

A)  narrower 
B)  the same 
C)  wider 
D)  more skewed

Exam 6: Where Am I Normal Distributions and Standard Scores

The 3-sigma rule is violated when the mean, mode and median are the same value.

The closer the score is to the mean, the less frequent it is in the distribution.

Which of the following information is missing from non-standard scores that is present in standard scores?

Jessica scores the same as the mean on a test. Her z-score is zero.

An individual who scores higher than the mean on a test will have a z-score that is negative.

In a symmetric distribution, the probability of obtaining a z-score above 3 is exactly the same as the probability of obtaining a z-score below -3.

Kristie's z-score is -2.01 on a test with a mean of 70 and standard deviation of 2. What is her raw score? Round your answer to the nearest whole number.

If you obtain an observed z-score that is larger than critical z, you should always reject the null hypothesis.

Someone's z-score on a test can only be known if we know both the population mean of the test and the standard deviation.

The z-test is a popular test because it is easy to calculate and does not make assumptions about the distribution of the data.

Last semester, Julia scored 140 on an intelligence test with a mean of 100 and standard deviation of 10. This year, she scored 100 on a different intelligence test with a mean of 60 and standard deviation of 10. Which of the following statements is true in relation to Julia's scores?

A test of spatial skills has a mean of 70 and a standard deviation of 6. A different test for vocabulary knowledge has the same mean and standard deviation. Which of the following options is true?

A deviation score is the numerator of the formula for calculating a z-score.

Suzanne would like to calculate the z-score of her height relative to the height of ballerinas. She is 5'7. What other information does she need to obtain the z-score of her height?

Josh's z-score on a test is -0.5. Which of the following options must be true?

Lewis obtained a score of 45 on a test with a mean of 55 and a standard deviation of 10. What is the percentile of Lewis' score? Round your answer to the nearest whole number.

A test of spatial skills has a mean of 80 and a standard deviation of 5. A newer, different test that also measures spatial skills has a mean of 100 and a standard deviation of 2. The distribution of the older test is ________________ than the distribution of the newer test.