Question 1

Under the normal curve, when the z score is equal to + 1, then

Accepted Answer

A)  the standard deviation of the distribution of raw scores must equal 15 
B)  the standard deviation of the distribution of raw scores must equal 10 
C)  the standard deviation of the distribution of raw scores must equal 0 
D)  none of these 
A)  the standard deviation of the distribution of raw scores must equal 15 
B)  the standard deviation of the distribution of raw scores must equal 10 
C)  the standard deviation of the distribution of raw scores must equal 0 
D)  none of these

Question 2

Fewer than 50% of the cases may ever fall between two z scores of the same sign.

Accepted Answer

A) True 
 B)False

Question 3

A negative z score always means that the raw score is less than the mean.

Accepted Answer

A) True 
 B)False

Question 4

Find the percentiles for the following: the mean score on a test of psychopathy among a group of incarcerated inmates is 50, with a standard deviation of 10. Assume a normal distribution, and find the Percentile for the following psychopathy scores:
-75

Accepted Answer

99.39 or 9

Question 5

Find the percentiles for the following: the mean score on a test of psychopathy among a group of incarcerated inmates is 50, with a standard deviation of 10. Assume a normal distribution, and find the Percentile for the following psychopathy scores:
-57

Accepted Answer

75.80 or 7

Question 6

The normal distribution curve is unimodal.

Accepted Answer

A) True 
 B)False

Question 7

The mean weight among a group of female high school seniors is 120 lbs., with a standard deviation of 16.49 lbs. Assuming a normal distribution, find the percentiles for the following weight scores
-140 lbs.

Accepted Answer

88.69 or 8

Question 8

Percentage of scores falling below a z of 2.56

Accepted Answer

The answer of Percentage of scores falling below a z...

Question 9

Percentage of scores falling below a z of 1.44

Accepted Answer

The answer of Percentage of scores falling below a z...

Question 10

Between the raw scores of 400 and 600, there must be

Accepted Answer

A)  50% of the scores 
B)  34% of the scores 
C)  68% of the scores 
D)  95% of the scores 
A)  50% of the scores 
B)  34% of the scores 
C)  68% of the scores 
D)  95% of the scores

Question 11

A raw score of 500 would translate into a z score of

Accepted Answer

A)  -3 
B)  -1 
C)  -.01 
D)  0 
A)  -3 
B)  -1 
C)  -.01 
D)  0

Question 12

Approximately 68% of all the scores would fall

Accepted Answer

A)  between raw scores of 400 and 600 
B)  between raw scores of 200 and 500 
C)  between raw scores of 500 and 600 
D)  above a raw score of 700 
A)  between raw scores of 400 and 600 
B)  between raw scores of 200 and 500 
C)  between raw scores of 500 and 600 
D)  above a raw score of 700

Question 13

When the standard deviation of the raw score distribution is negative, the resulting z score must be

Accepted Answer

A)  negative 
B)  equal to 0 
C)  positive 
D)  none of these, since the standard deviation can never be negative 
A)  negative 
B)  equal to 0 
C)  positive 
D)  none of these, since the standard deviation can never be negative

Question 14

When any frequency distribution curve is symmetrical, it must, by definition, also be normal.

Accepted Answer

A) True 
 B)False

Question 15

All percentiles of less than 50 must necessarily

Accepted Answer

A)  fall below the raw score mean 
B)  yield negative z scores 
C)  fall to the left of the z score mean 
D)  all of these 
A)  fall below the raw score mean 
B)  yield negative z scores 
C)  fall to the left of the z score mean 
D)  all of these

Question 16

Percentage of scores falling below a z of -.24

Accepted Answer

The answer of Percentage of scores falling below a z...

Question 17

The z score table always gives, as a direct read-out, the percentage of cases falling

Accepted Answer

A)  between a given z score and the mean 
B)  below a negative z score 
C)  above a positive z score 
D)  none of these 
A)  between a given z score and the mean 
B)  below a negative z score 
C)  above a positive z score 
D)  none of these

Question 18

If an IQ distribution is normal and has a mean of 100 and a standard deviation of 15, then 99% of all those taking the test scored between IQ's of

Accepted Answer

A)  0 and 150 
B)  55 and 145 
C)  85 and 115 
D)  92.5 and 107.5 
A)  0 and 150 
B)  55 and 145 
C)  85 and 115 
D)  92.5 and 107.5

Question 19

Under the normal curve, 68% of the cases must always fall

Accepted Answer

A)  above the mean 
B)  between + 1 standard deviation units from the mean 
C)  between + 2 standard deviation units from the mean 
D)  all of these, depending on the particular shape of the curve 
A)  above the mean 
B)  between + 1 standard deviation units from the mean 
C)  between + 2 standard deviation units from the mean 
D)  all of these, depending on the particular shape of the curve

Question 20

Under the normal curve

Accepted Answer

A)  the mean lies to the right of the median 
B)  the mode lies to the left of the mean 
C)  the median lies to the left of the mode 
D)  none of these 
A)  the mean lies to the right of the median 
B)  the mode lies to the left of the mean 
C)  the median lies to the left of the mode 
D)  none of these

Under the normal curve, when the z score is equal to + 1, then

Fewer than 50% of the cases may ever fall between two z scores of the same sign.

A negative z score always means that the raw score is less than the mean.

Find the percentiles for the following: the mean score on a test of psychopathy among a group of incarcerated inmates is 50, with a standard deviation of 10. Assume a normal distribution, and find the Percentile for the following psychopathy scores: -75

Find the percentiles for the following: the mean score on a test of psychopathy among a group of incarcerated inmates is 50, with a standard deviation of 10. Assume a normal distribution, and find the Percentile for the following psychopathy scores: -57

The normal distribution curve is unimodal.

The mean weight among a group of female high school seniors is 120 lbs., with a standard deviation of 16.49 lbs. Assuming a normal distribution, find the percentiles for the following weight scores -140 lbs.

Percentage of scores falling below a z of 2.56

Percentage of scores falling below a z of 1.44

Between the raw scores of 400 and 600, there must be

A raw score of 500 would translate into a z score of

Approximately 68% of all the scores would fall

When the standard deviation of the raw score distribution is negative, the resulting z score must be

When any frequency distribution curve is symmetrical, it must, by definition, also be normal.

All percentiles of less than 50 must necessarily

Percentage of scores falling below a z of -.24

The z score table always gives, as a direct read-out, the percentage of cases falling

If an IQ distribution is normal and has a mean of 100 and a standard deviation of 15, then 99% of all those taking the test scored between IQ's of

Under the normal curve, 68% of the cases must always fall

Under the normal curve

Introduction to Statistics

Percentages, Graphs and Measures of Central Tendency

Measures of Variability

Z Scores, T Scores and Other Normal Curve Transformations

Probability

Statistics and Parameters

Parameter Estimates

The Fundamentals of Research Methodology

The Hypothesis of Difference

The Hypothesis of Association: Correlation

Analysis of Variance

Nominal Categorical Data and the Chi Square

Regression Analysis

Repeated-Measures and Matched-Subjects Designs Interval Data

Non-Parametrics Revisited: the Ordinal Case

Tests and Measurements

Filters

Exam 4: The Normal Curve and Z Score

Under the normal curve, when the z score is equal to + 1, then

Fewer than 50% of the cases may ever fall between two z scores of the same sign.

A negative z score always means that the raw score is less than the mean.

Find the percentiles for the following: the mean score on a test of psychopathy among a group of incarcerated inmates is 50, with a standard deviation of 10. Assume a normal distribution, and find the Percentile for the following psychopathy scores: -75

Find the percentiles for the following: the mean score on a test of psychopathy among a group of incarcerated inmates is 50, with a standard deviation of 10. Assume a normal distribution, and find the Percentile for the following psychopathy scores: -57

The normal distribution curve is unimodal.

The mean weight among a group of female high school seniors is 120 lbs., with a standard deviation of 16.49 lbs. Assuming a normal distribution, find the percentiles for the following weight scores -140 lbs.

Percentage of scores falling below a z of 2.56

Percentage of scores falling below a z of 1.44

Between the raw scores of 400 and 600, there must be

A raw score of 500 would translate into a z score of

Approximately 68% of all the scores would fall

When the standard deviation of the raw score distribution is negative, the resulting z score must be

When any frequency distribution curve is symmetrical, it must, by definition, also be normal.

All percentiles of less than 50 must necessarily

Percentage of scores falling below a z of -.24

The z score table always gives, as a direct read-out, the percentage of cases falling

If an IQ distribution is normal and has a mean of 100 and a standard deviation of 15, then 99% of all those taking the test scored between IQ's of

Under the normal curve, 68% of the cases must always fall

Under the normal curve

Introduction to Statistics

Percentages, Graphs and Measures of Central Tendency

Measures of Variability

Z Scores, T Scores and Other Normal Curve Transformations

Probability

Statistics and Parameters

Parameter Estimates

The Fundamentals of Research Methodology

The Hypothesis of Difference

The Hypothesis of Association: Correlation

Analysis of Variance

Nominal Categorical Data and the Chi Square

Regression Analysis

Repeated-Measures and Matched-Subjects Designs Interval Data

Non-Parametrics Revisited: the Ordinal Case

Tests and Measurements

Filters