Question 1

The ______ of the ______ is equal to ______.

Accepted Answer

A)  mean; standard normal distribution; σ 
B)  standard deviation; normal distribution; μ 
C)  mean; standard normal distribution; 0 
D)  standard deviation; standard normal distribution; μ 
A)  mean; standard normal distribution; σ 
B)  standard deviation; normal distribution; μ 
C)  mean; standard normal distribution; 0 
D)  standard deviation; standard normal distribution; μ

Question 2

Normal distributions ______.

Accepted Answer

A)  are skewed (asymmetrical) 
B)  contain an infinite number of scores 
C)  are bimodal 
D)  always consist of both positive and negative scores 
A)  are skewed (asymmetrical) 
B)  contain an infinite number of scores 
C)  are bimodal 
D)  always consist of both positive and negative scores

Question 3

"Your score on this variable is about one-half of a standard deviation below the mean." Which of the following statements is MOST accurate?

Accepted Answer

A)  Your z-score is 1.51. 
B)  Your z-score is -1.47. 
C)  Your z-score is -.53. 
D)  You cannot estimate your z-score with the information provided. 
A)  Your z-score is 1.51. 
B)  Your z-score is -1.47. 
C)  Your z-score is -.53. 
D)  You cannot estimate your z-score with the information provided.

Question 4

What percentage of z-scores in the standard normal distribution are between z = -.20 and z = .40?

Accepted Answer

A)  7.53% 
B)  23.07% 
C)  42.07% 
D)  76.93% 
A)  7.53% 
B)  23.07% 
C)  42.07% 
D)  76.93%

Question 5

If a variable is normally distributed with a hypothesized mean (μ) of 32 and a standard deviation (σ) of 5, what is the z-score for a raw score (X) of 41?

Accepted Answer

A)  z = 1.80 
B)  z = -1.80 
C)  z = 46.41 
D)  z = 9 
A)  z = 1.80 
B)  z = -1.80 
C)  z = 46.41 
D)  z = 9

Question 6

What percentage of z-scores in the standard normal distribution are less than z = .20?

Accepted Answer

A)  42.07% 
B)  57.93% 
C)  84.00% 
D)  92.07% 
A)  42.07% 
B)  57.93% 
C)  84.00% 
D)  92.07%

Question 7

Normal distributions ______.

Accepted Answer

A)  are based on data collected from populations 
B)  are based on mathematical formulas 
C)  consist of a small number of scores 
D)  are a figment of our imagination 
A)  are based on data collected from populations 
B)  are based on mathematical formulas 
C)  consist of a small number of scores 
D)  are a figment of our imagination

Question 8

The ______ of the standard normal distribution is equal to ______.

Accepted Answer

A)  mean; σ 
B)  standard deviation; 0 
C)  standard deviation; μ 
D)  mean; 0 
A)  mean; σ 
B)  standard deviation; 0 
C)  standard deviation; μ 
D)  mean; 0

Question 9

About ____ of z-scores in the standard normal distribution are within ±2 standard deviations of the mean.

Accepted Answer

A)  one-fourth 
B)  half 
C)  two-thirds 
D)  95% 
A)  one-fourth 
B)  half 
C)  two-thirds 
D)  95%

Question 10

About ______ of z-scores in the standard normal distribution are between the z-scores ±1.96.

Accepted Answer

A)  one-third 
B)  half 
C)  two-thirds 
D)  95% 
A)  one-third 
B)  half 
C)  two-thirds 
D)  95%

Question 11

Imagine the average score on this exam ends up being 71 with a standard deviation of 10. If scores are normally distributed, ______ is the lowest score that would place you in the top 20% of the class.

Accepted Answer

A)  71 
B)  76 
C)  80 
D)  84 
A)  71 
B)  76 
C)  80 
D)  84

Question 12

"Your z-score is in the top 5% of the class." Which of the following statements is MOST accurate?

Accepted Answer

A)  Your z-score is 5. 
B)  Your z-score is 2. 
C)  Your z-score is 0. 
D)  Your z-score is 1. 
A)  Your z-score is 5. 
B)  Your z-score is 2. 
C)  Your z-score is 0. 
D)  Your z-score is 1.

Question 13

For a variable that is normally distributed with a mean of 100 and a standard deviation of 25, approximately ______ of the scores are between ______ and ______.

Accepted Answer

A)  68%; 75 and 125 
B)  68%; 50 and 150 
C)  95%; 100 and 150 
D)  95%; 100 and 200 
A)  68%; 75 and 125 
B)  68%; 50 and 150 
C)  95%; 100 and 150 
D)  95%; 100 and 200

Question 14

What percentage of z-scores in the standard normal distribution are less than z = -.35?

Accepted Answer

A)  13.68% 
B)  36.32% 
C)  63.68% 
D)  86.32% 
A)  13.68% 
B)  36.32% 
C)  63.68% 
D)  86.32%

Question 15

Standard normal distribution scores are also known as ______.

Accepted Answer

A)  frequencies 
B)  normal scores 
C)  z-scores 
D)  standard scores 
A)  frequencies 
B)  normal scores 
C)  z-scores 
D)  standard scores

Question 16

"According to the National Center for Health Statistics, in 2005 the average birthweight of a newborn baby was approximately normally distributed with a mean of 119 ounces (7 lb, 7 oz) and a standard deviation of 19 ounces." A 'low birthweight' baby is one who weighs less than 88 ounces (5 lb, 8 oz) at birth. What percentage of babies are low birthweight?

Accepted Answer

A)  5.16% 
B)  44.84% 
C)  55.16% 
D)  94.84% 
A)  5.16% 
B)  44.84% 
C)  55.16% 
D)  94.84%

Question 17

"A study examining people's water consumption estimated men spend an average of 10.4 minutes taking a shower, with a standard deviation of 4.8 minutes (Shimokura et al., 1998)." What percentage of men spend more than 15 minutes taking a shower?

Accepted Answer

A)  .96% 
B)  16.85% 
C)  33.15% 
D)  83.15% 
A)  .96% 
B)  16.85% 
C)  33.15% 
D)  83.15%

Question 18

An instructor transforms her students' scores on a midterm into standardized (z) scores. Which of the following is by definition true about the distribution of standardized scores?

Accepted Answer

A)  The distribution is normally distributed. 
B)  The mean of the standardized scores is equal to μ. 
C)  The shape of the distribution of standardized scores is identical to the distribution of midterm scores. 
D)  The distribution contains an infinite number of scores. 
A)  The distribution is normally distributed. 
B)  The mean of the standardized scores is equal to μ. 
C)  The shape of the distribution of standardized scores is identical to the distribution of midterm scores. 
D)  The distribution contains an infinite number of scores.

Question 19

What percentage of z-scores in the standard normal distribution are greater than z = .65?

Accepted Answer

A)  .65% 
B)  24.22% 
C)  25.78% 
D)  74.22% 
A)  .65% 
B)  24.22% 
C)  25.78% 
D)  74.22%

Question 20

The shaded area in this distribution most closely represents ______.

Accepted Answer

A)  55% of all z-scores 
B)  the % of z-scores between -.70 and -2.03 
C)  the % of z-scores between .80 and 1.98 
D)  the % of z-scores less than -2.01 
A)  55% of all z-scores 
B)  the % of z-scores between -.70 and -2.03 
C)  the % of z-scores between .80 and 1.98 
D)  the % of z-scores less than -2.01

The of the is equal to __.

Normal distributions ______.

"Your score on this variable is about one-half of a standard deviation below the mean." Which of the following statements is MOST accurate?

What percentage of z-scores in the standard normal distribution are between z = -.20 and z = .40?

If a variable is normally distributed with a hypothesized mean (μ) of 32 and a standard deviation (σ) of 5, what is the z-score for a raw score (X) of 41?

What percentage of z-scores in the standard normal distribution are less than z = .20?

Normal distributions ______.

The of the standard normal distribution is equal to .

About ____ of z-scores in the standard normal distribution are within ±2 standard deviations of the mean.

About ______ of z-scores in the standard normal distribution are between the z-scores ±1.96.

Imagine the average score on this exam ends up being 71 with a standard deviation of 10. If scores are normally distributed, ______ is the lowest score that would place you in the top 20% of the class.

"Your z-score is in the top 5% of the class." Which of the following statements is MOST accurate?

For a variable that is normally distributed with a mean of 100 and a standard deviation of 25, approximately of the scores are between and __.

What percentage of z-scores in the standard normal distribution are less than z = -.35?

Standard normal distribution scores are also known as ______.

"A study examining people's water consumption estimated men spend an average of 10.4 minutes taking a shower, with a standard deviation of 4.8 minutes (Shimokura et al., 1998)." What percentage of men spend more than 15 minutes taking a shower?

An instructor transforms her students' scores on a midterm into standardized (z) scores. Which of the following is by definition true about the distribution of standardized scores?

What percentage of z-scores in the standard normal distribution are greater than z = .65?

The shaded area in this distribution most closely represents ______.

Introduction to Statistics

Examining Data: Tables and Figures

Measures of Central Tendency

Measures of Variability

Probability and Hypothesis Testing

Testing One Sample Mean

Estimating the Mean of a Population

Testing the Difference Between Two Means

Errors in Hypothesis Testing, Statistical Power, and Effect Size

One-Way Analysis of Variance Anova

Two-Way Analysis of Variance Anova

Correlation

Linear Regression and Multiple Correlation

Chi-Square

Filters

Exam 5: Normal Distributions

The ______ of the ______ is equal to ______.

Normal distributions ______.

"Your score on this variable is about one-half of a standard deviation below the mean." Which of the following statements is MOST accurate?

What percentage of z-scores in the standard normal distribution are between z = -.20 and z = .40?

If a variable is normally distributed with a hypothesized mean (μ) of 32 and a standard deviation (σ) of 5, what is the z-score for a raw score (X) of 41?

What percentage of z-scores in the standard normal distribution are less than z = .20?

Normal distributions ______.

The ______ of the standard normal distribution is equal to ______.

About ____ of z-scores in the standard normal distribution are within ±2 standard deviations of the mean.

About ______ of z-scores in the standard normal distribution are between the z-scores ±1.96.

Imagine the average score on this exam ends up being 71 with a standard deviation of 10. If scores are normally distributed, ______ is the lowest score that would place you in the top 20% of the class.

"Your z-score is in the top 5% of the class." Which of the following statements is MOST accurate?

For a variable that is normally distributed with a mean of 100 and a standard deviation of 25, approximately ______ of the scores are between ______ and ______.

What percentage of z-scores in the standard normal distribution are less than z = -.35?

Standard normal distribution scores are also known as ______.

"A study examining people's water consumption estimated men spend an average of 10.4 minutes taking a shower, with a standard deviation of 4.8 minutes (Shimokura et al., 1998)." What percentage of men spend more than 15 minutes taking a shower?

An instructor transforms her students' scores on a midterm into standardized (z) scores. Which of the following is by definition true about the distribution of standardized scores?

What percentage of z-scores in the standard normal distribution are greater than z = .65?

The shaded area in this distribution most closely represents ______.

Introduction to Statistics

Examining Data: Tables and Figures

Measures of Central Tendency

Measures of Variability

Probability and Hypothesis Testing

Testing One Sample Mean

Estimating the Mean of a Population

Testing the Difference Between Two Means

Errors in Hypothesis Testing, Statistical Power, and Effect Size

One-Way Analysis of Variance Anova

Two-Way Analysis of Variance Anova

Correlation

Linear Regression and Multiple Correlation

Chi-Square

Filters

The of the is equal to __.

The of the standard normal distribution is equal to .

For a variable that is normally distributed with a mean of 100 and a standard deviation of 25, approximately of the scores are between and __.