Question 1

In general,the larger the value of the standard deviation,

Accepted Answer

A) the less spread out the distribution. 
B) the more tightly packed the distribution around the mean. 
C) the wider the distribution. 
D) the more asymmetrical the distribution. 
A) the less spread out the distribution. 
B) the more tightly packed the distribution around the mean. 
C) the wider the distribution. 
D) the more asymmetrical the distribution.

Question 2

A group of 10 students participated in a study of nutritional awareness.What is the sample standard deviation   of their scores? Their scores follow: 20,19,22,20,15,18,15,21,19,20

Accepted Answer

A) 2.21 
B) 2.33 
C) 4.89 
D) 5.43 
A) 2.21 
B) 2.33 
C) 4.89 
D) 5.43

Question 3

If you see the notation   you should

Accepted Answer

A) sum all the Xs,then square the sum. 
B) sum the Xs,then divide by 2. 
C) square all the Xs,then sum the squares. 
D) divide all the Xs by 2. 
A) sum all the Xs,then square the sum. 
B) sum the Xs,then divide by 2. 
C) square all the Xs,then sum the squares. 
D) divide all the Xs by 2.

Question 4

Which of the following mathematically indicates the amount a score deviates from the mean?

Accepted Answer

A)    
B)    
C)    
D)    
A)    
B)    
C)    
D)

Question 5

The Red Cross wanted to know whether an ad campaign designed to persuade people to donate blood actually increased blood donations.For a sample of N = 4 blood donation centers,the mean increase in blood donations was 10 pints,with a standard deviation of 2 pints.If the Red Cross could collect data from the entire population of blood donation centers,what would one expect the population standard deviation to be?

Accepted Answer

A) 2 
B) 2.31 
C) 2.67 
D) 20 
A) 2 
B) 2.31 
C) 2.67 
D) 20

Question 6

is used to describe _____;   describes _____;   describes _____.

Accepted Answer

A) the estimate of the population variance;the population variance;the sample variance 
B) the sample variance;the population variance;the population variance 
C) the sample variance;the sample variance;the population variance 
D) the sample variance;the estimate of the population variance;the population variance 
A) the estimate of the population variance;the population variance;the sample variance 
B) the sample variance;the population variance;the population variance 
C) the sample variance;the sample variance;the population variance 
D) the sample variance;the estimate of the population variance;the population variance

Question 7

In roughly normal distributions,the standard deviation is approximately

Accepted Answer

A) equivalent to the variance. 
B) one-sixth of the range. 
C) equivalent to the deviation of the median from the mean. 
D) one-fifth of the absolute value of the mean. 
A) equivalent to the variance. 
B) one-sixth of the range. 
C) equivalent to the deviation of the median from the mean. 
D) one-fifth of the absolute value of the mean.

Question 8

The term variability is most opposite to

Accepted Answer

A) central tendency 
B) consistency 
C) association 
D) homoscedasticity 
A) central tendency 
B) consistency 
C) association 
D) homoscedasticity

Question 9

If the sample standard deviation   for a set of data with N = 6 is found to be 3.17,then what would be the estimated population standard deviation   ?

Accepted Answer

A) 3.47 
B) 1.78 
C) 12.06 
D) 10.05 
A) 3.47 
B) 1.78 
C) 12.06 
D) 10.05

Question 10

When computing the variance,why do we square the deviations from the mean?

Accepted Answer

A) To return the units of measure to their original form 
B) To compensate for the fact that the number of degrees of freedom is different from N 
C) To transform the raw scores into squared scores 
D) To compensate for the fact that deviations about the mean always sum to zero 
A) To return the units of measure to their original form 
B) To compensate for the fact that the number of degrees of freedom is different from N 
C) To transform the raw scores into squared scores 
D) To compensate for the fact that deviations about the mean always sum to zero

Question 11

If we are going to predict future performance on the basis of a sample mean and sample standard deviation,it is desirable to have a

Accepted Answer

A) small mean. 
B) small standard deviation. 
C) large mean. 
D) large standard deviation. 
A) small mean. 
B) small standard deviation. 
C) large mean. 
D) large standard deviation.

Question 12

Which of the following is not communicated by a measure of variability?

Accepted Answer

A) The location of the distribution 
B) How consistently close to the mean the scores are 
C) How spread out the distribution is 
D) The differences among the scores 
A) The location of the distribution 
B) How consistently close to the mean the scores are 
C) How spread out the distribution is 
D) The differences among the scores

Question 13

Measures of central tendency indicate the _____ of a distribution;measures of variability indicate the _____ between the scores in a distribution.

Accepted Answer

A) similarities;differences 
B) mean;variance 
C) location;distance 
D) distance;location 
A) similarities;differences 
B) mean;variance 
C) location;distance 
D) distance;location

Question 14

and   are considered biased estimates for the population standard deviation and variance because,over many calculations,they tend to be

Accepted Answer

A) overestimates. 
B) underestimates. 
C) inaccurate in an unpredictable way. 
D) accurate estimates. 
A) overestimates. 
B) underestimates. 
C) inaccurate in an unpredictable way. 
D) accurate estimates.

Question 15

A group of 10 students participated in a study of nutritional awareness.What is the estimated population standard deviation   ? 20,19,22,20,15,18,15,21,19,20

Accepted Answer

A) 5.43 
B) 2.21 
C) 4.89 
D) 2.33 
A) 5.43 
B) 2.21 
C) 4.89 
D) 2.33

Question 16

When all the scores in a set of data are the same,what is   ?

Accepted Answer

A) 0 
B) Greater than 0 
C) Less than 0 
D) Unknown;cannot compute without the scores 
A) 0 
B) Greater than 0 
C) Less than 0 
D) Unknown;cannot compute without the scores

Question 17

Sample variance is defined as the

Accepted Answer

A) average of the deviations around the sample mean. 
B) average of the squared deviations of scores around the sample mean. 
C) sum of the deviations around the sample mean,squared. 
D) sum of the squared deviations around the sample mean. 
A) average of the deviations around the sample mean. 
B) average of the squared deviations of scores around the sample mean. 
C) sum of the deviations around the sample mean,squared. 
D) sum of the squared deviations around the sample mean.

Question 18

A program evaluator for a large school district wants to study intelligence in the elementary schools.She randomly selects one classroom at each grade level in each elementary school and administers an intelligence test to the children in those classrooms.If the program evaluator wants to find out which school has the highest intelligence level,which of the following should she calculate for each school?

Accepted Answer

A) The variance 
B) The standard deviation 
C) The percentile 
D) The mean 
A) The variance 
B) The standard deviation 
C) The percentile 
D) The mean

Question 19

In the language of statistics,how well a relationship helps predict different Y scores is the extent it

Accepted Answer

A) reduce the variance. 
B) increase the variance. 
C) accounts for the variance in X scores. 
D) accounts for the variance in Y scores. 
A) reduce the variance. 
B) increase the variance. 
C) accounts for the variance in X scores. 
D) accounts for the variance in Y scores.

In general,the larger the value of the standard deviation,

A group of 10 students participated in a study of nutritional awareness.What is the sample standard deviation of their scores? Their scores follow: 20,19,22,20,15,18,15,21,19,20

If you see the notation you should

Which of the following mathematically indicates the amount a score deviates from the mean?

is used to describe ___; describes _; describes ___.

In roughly normal distributions,the standard deviation is approximately

The term variability is most opposite to

If the sample standard deviation for a set of data with N = 6 is found to be 3.17,then what would be the estimated population standard deviation ?

When computing the variance,why do we square the deviations from the mean?

If we are going to predict future performance on the basis of a sample mean and sample standard deviation,it is desirable to have a

Which of the following is not communicated by a measure of variability?

Measures of central tendency indicate the _ of a distribution;measures of variability indicate the _ between the scores in a distribution.

and are considered biased estimates for the population standard deviation and variance because,over many calculations,they tend to be

A group of 10 students participated in a study of nutritional awareness.What is the estimated population standard deviation ? 20,19,22,20,15,18,15,21,19,20

When all the scores in a set of data are the same,what is ?

Sample variance is defined as the

In the language of statistics,how well a relationship helps predict different Y scores is the extent it

Introduction to Statistics

Statistics and the Research Process

Frequency Distributions and Percentiles

Measures of Central Tendency;the Mean, median, and Mode

Z-Scores and the Normal Curve

The Correlation Coefficient

Linear Regression

Using Probability to Make Decisions About Data

Introduction to Hypothesis Testing

Performing the One-Sample T-Test and Testing Correlation Coefficients

The Two-Sample T-Test

The One-Way Analysis of Variance

The Two-Way Analysis of Variance

Chi Square and Other Nonparametric Procedures

Filters

Exam 5: Measures of Variability: Range, variance, and Standard Deviation

In general,the larger the value of the standard deviation,

A group of 10 students participated in a study of nutritional awareness.What is the sample standard deviation of their scores? Their scores follow: 20,19,22,20,15,18,15,21,19,20

If you see the notation you should

Which of the following mathematically indicates the amount a score deviates from the mean?

is used to describe _____; describes _____; describes _____.

In roughly normal distributions,the standard deviation is approximately

The term variability is most opposite to

If the sample standard deviation for a set of data with N = 6 is found to be 3.17,then what would be the estimated population standard deviation ?

When computing the variance,why do we square the deviations from the mean?

If we are going to predict future performance on the basis of a sample mean and sample standard deviation,it is desirable to have a

Which of the following is not communicated by a measure of variability?

Measures of central tendency indicate the _____ of a distribution;measures of variability indicate the _____ between the scores in a distribution.

and are considered biased estimates for the population standard deviation and variance because,over many calculations,they tend to be

A group of 10 students participated in a study of nutritional awareness.What is the estimated population standard deviation ? 20,19,22,20,15,18,15,21,19,20

When all the scores in a set of data are the same,what is ?

Sample variance is defined as the

In the language of statistics,how well a relationship helps predict different Y scores is the extent it

Introduction to Statistics

Statistics and the Research Process

Frequency Distributions and Percentiles

Measures of Central Tendency;the Mean, median, and Mode

Z-Scores and the Normal Curve

The Correlation Coefficient

Linear Regression

Using Probability to Make Decisions About Data

Introduction to Hypothesis Testing

Performing the One-Sample T-Test and Testing Correlation Coefficients

The Two-Sample T-Test

The One-Way Analysis of Variance

The Two-Way Analysis of Variance

Chi Square and Other Nonparametric Procedures

Filters

is used to describe ___; describes _; describes ___.

Measures of central tendency indicate the _ of a distribution;measures of variability indicate the _ between the scores in a distribution.