Question 1

A percentile is a measure of ____________________ standing.

Accepted Answer

The answer of A percentile is a measure of ____________________...

Question 2

Salaries of Employees
The following data represent the yearly salaries (in thousands of dollars)of a sample of 13 employees of a firm: 26.5,23.5,29.7,24.8,21.1,24.3,20.4,22.7,27.2,23.7,24.1,24.8,and 28.2.
-{Salaries of Employees Narrative} Compute the median salary.

Accepted Answer

median = 2

Question 3

The interquartile range is an interval of numbers starting at Q1 and ending at Q3.

Accepted Answer

A) True 
 B)False

Question 4

Suppose a sample of size 50 has a sample mean of 20.In this case,the sum of all observations in the sample is 1,000.

Accepted Answer

A) True 
 B)False

Question 5

In a positively skewed distribution,which of the following is the correct statement?

Accepted Answer

A)  The distance from Q1 to Q2 is larger than the distance from Q2 to Q3. 
B)  The distance from Q1 to Q2 is smaller than the distance from Q2 to Q3. 
C)  The distance from Q1 to Q2 is twice the distance from Q2 to Q3. 
D)  The distance from Q1 to Q2 is half the distance from Q2 to Q3. 
A)  The distance from Q1 to Q2 is larger than the distance from Q2 to Q3. 
B)  The distance from Q1 to Q2 is smaller than the distance from Q2 to Q3. 
C)  The distance from Q1 to Q2 is twice the distance from Q2 to Q3. 
D)  The distance from Q1 to Q2 is half the distance from Q2 to Q3.

Question 6

In a negatively skewed distribution,which of the following is the correct statement?

Accepted Answer

A)  The distance from Q1 to Q2 is smaller than the distance from Q2 to Q3. 
B)  The distance from Q1 to Q2 is larger than the distance from Q2 to Q3. 
C)  The distance from Q1 to Q2 is half the distance from Q2 to Q3. 
D)  The distance from Q1 to Q3 is twice the distance from the Q1 to Q2. 
A)  The distance from Q1 to Q2 is smaller than the distance from Q2 to Q3. 
B)  The distance from Q1 to Q2 is larger than the distance from Q2 to Q3. 
C)  The distance from Q1 to Q2 is half the distance from Q2 to Q3. 
D)  The distance from Q1 to Q3 is twice the distance from the Q1 to Q2.

Question 7

The interquartile range is a measure of variability in a set of data.

Accepted Answer

A) True 
 B)False

Question 8

The standard deviation is expressed in terms of the original units of measurement but the variance is not.

Accepted Answer

A) True 
 B)False

Question 9

Q2 is another name for the ____________________.

Accepted Answer

Question 10

Computers
The following data represent the number of computers owned by a sample of 10 families from Chicago: 4,2,1,1,5,3,0,1,0,and 2.
-{Computers Narrative} Is the distribution of the number of computers symmetric or skewed? Why?

Accepted Answer

The distribution is

Question 11

The interquartile range will always exceed that of the range.

Accepted Answer

A) True 
 B)False

Question 12

The interquartile range is the difference between the:

Accepted Answer

A)  largest and smallest numbers in the data set. 
B)  25th percentile and the 75th percentile. 
C)  median and the mean. 
D)  None of these choices. 
A)  largest and smallest numbers in the data set. 
B)  25th percentile and the 75th percentile. 
C)  median and the mean. 
D)  None of these choices.

Question 13

Weights of Police Officers
The following data represent the weights in pounds of a sample of 25 police officers: 164,148,137,157,173,156,177,172,169,165,145,168,163,162,174,152,156,168,154,151,174,146,134,140,and 171.
-{Weights of Police Officers Narrative} Determine the location and value of the upper quartile of the weights.

Accepted Answer

Location = L<sub>75<

Question 14

Expressed in percentiles,the interquartile range is the difference between the 25th and 75th percentiles.

Accepted Answer

A) True 
 B)False

Question 15

Yearly Donations
The following data represent the yearly donations (in thousands of dollars)of a sample of 13 benefactors: 26.5,23.5,29.7,24.8,21.1,24.3,20.4,22.7,27.2,23.7,24.1,24.8,and 28.2.
-{Yearly Donations Narrative} Compute the upper quartile.

Accepted Answer

Location = L₇₅ = 10

Question 16

Weights of Police Officers
The following data represent the weights in pounds of a sample of 25 police officers: 164,148,137,157,173,156,177,172,169,165,145,168,163,162,174,152,156,168,154,151,174,146,134,140,and 171.
-{Weights of Police Officers Narrative} What does the histogram tell you about the distribution of the weights of workers?

Accepted Answer

The histog

Question 17

Ages of Workers
The ages (in years)of three groups of workers are shown below:
 $$\begin{array} { c l l l l l } 
\text { Group A: } & 17 & 22 & 20 & 18 & 23 \
\text { Group B: } & 30 & 28 & 35 & 40 & 25 \
\text { GroupC:} & 44 & 39 & 54 & 21 & 52
\end{array}$$
-{Ages of Workers Narrative} Calculate and compare the standard deviations for the three samples.

Accepted Answer

s = 2.55 years,5.94 years,and 13.21 year

Question 18

Lily has been keeping track of what she spends to eat out.The last week's expenditures for meals eaten out were $5.69,$5.95,$6.19,$10.91,$7.49,$14.53,and $7.66.The mean amount Lily spends on meals is $8.35.

Accepted Answer

A) True 
 B)False

Question 19

In a histogram,the proportion of the total area which must be to the left of the median is:

Accepted Answer

A)  exactly 0.50. 
B)  less than 0.50 if the distribution is negatively skewed. 
C)  more than 0.50 if the distribution is positively skewed. 
D)  unknown. 
A)  exactly 0.50. 
B)  less than 0.50 if the distribution is negatively skewed. 
C)  more than 0.50 if the distribution is positively skewed. 
D)  unknown.

Question 20

Ages of Jockeys
The following data represent the ages in years of a sample of 25 jockeys from a local race track: 31,43,56,23,49,42,33,61,44,28,48,38,44,35,40,64,52,42,47,39,53,27,36,35,and 20.
-{Ages of Jockeys Narrative} Compute the interquartile range of the data and interpret its meaning.

Accepted Answer

Interquartile range = Q<sub>3<

Exam 4: A: Numerical Descriptive Techniques

A percentile is a measure of ____________________ standing.

Salaries of Employees The following data represent the yearly salaries (in thousands of dollars)of a sample of 13 employees of a firm: 26.5,23.5,29.7,24.8,21.1,24.3,20.4,22.7,27.2,23.7,24.1,24.8,and 28.2. -{Salaries of Employees Narrative} Compute the median salary.

The interquartile range is an interval of numbers starting at Q1 and ending at Q3.

Suppose a sample of size 50 has a sample mean of 20.In this case,the sum of all observations in the sample is 1,000.

In a positively skewed distribution,which of the following is the correct statement?

In a negatively skewed distribution,which of the following is the correct statement?

The interquartile range is a measure of variability in a set of data.

The standard deviation is expressed in terms of the original units of measurement but the variance is not.

Q2 is another name for the ____________________.

Computers The following data represent the number of computers owned by a sample of 10 families from Chicago: 4,2,1,1,5,3,0,1,0,and 2. -{Computers Narrative} Is the distribution of the number of computers symmetric or skewed? Why?

The interquartile range will always exceed that of the range.

The interquartile range is the difference between the:

Expressed in percentiles,the interquartile range is the difference between the 25th and 75th percentiles.

Yearly Donations The following data represent the yearly donations (in thousands of dollars)of a sample of 13 benefactors: 26.5,23.5,29.7,24.8,21.1,24.3,20.4,22.7,27.2,23.7,24.1,24.8,and 28.2. -{Yearly Donations Narrative} Compute the upper quartile.

Ages of Workers The ages (in years)of three groups of workers are shown below: Group A: 17 22 20 18 23 Group B: 30 28 35 40 25 GroupC: 44 39 54 21 52 -{Ages of Workers Narrative} Calculate and compare the standard deviations for the three samples.

Lily has been keeping track of what she spends to eat out.The last week's expenditures for meals eaten out were $5.69,$5.95,$6.19,$10.91,$7.49,$14.53,and $7.66.The mean amount Lily spends on meals is $8.35.

In a histogram,the proportion of the total area which must be to the left of the median is:

Ages of Jockeys The following data represent the ages in years of a sample of 25 jockeys from a local race track: 31,43,56,23,49,42,33,61,44,28,48,38,44,35,40,64,52,42,47,39,53,27,36,35,and 20. -{Ages of Jockeys Narrative} Compute the interquartile range of the data and interpret its meaning.

What Is Statistics

Graphical Descriptive Techniques I

Graphical Descriptive Techniques II

B: Numerical Descriptive Techniques

C: Numerical Descriptive Techniques

Data Collection and Sampling

Probability

A: Random Variables and Discrete Probability Distributions

B: Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations

Analysis of Variance

Chi-Squared Tests

A: Simple Linear Regression and Correlation

B: Simple Linear Regression and Correlation

Multiple Regression

Model Building

Nonparametric Statistics

Time-Series Analysis and Forecasting

Statistical Process Control

Decision Analysis

Conclusion

Filters

The interquartile range is an interval of numbers starting at Q₁ and ending at Q₃.

Q₂ is another name for the ____________________.