Bundle: Understanding Basic Statistics, Loose-leaf Version, 8th + WebAssign Printed Access Card, Single-Term
8th Edition
ISBN: 9781337888981
Author: Charles Henry Brase, Corrinne Pellillo Brase
Publisher: Cengage Learning
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Chapter 3.2, Problem 26P
Expand Your knowledge: Moving Averages You do not need a lot of money to invest in a mutual fund. However, if you decide to put some money into an investment, you are usually advised to leave it in for (at least) several years. Why? Because good years tend to cancel out had years, giving you a better overall return with less risk. To see what we
| Year | 1 | 2 | 3 | 4 | S | 6 | 7 | 8 | 9 | 10 | 11 |
| % Return | 1.78 | 17.79 | 744 | 5.95 | -4.74 | 25.85 | 9.03 | 18.92 | 17.49 | 6.80 | -2.38 |
Source Fund Reports
(a) Use a calculator with mean and standard deviation keys to verify that the mean annual return for all 11 years is approximately 9.45%, with standard deviation 9.57%.
(b) To compute a 3-year moving average for 1992. we take the data values for year 3 and the poor 2 years and average them. To compute a 3-year moving average for year 4, we take the data values for year 4 and the poor 2 years and average them. Verify that the following 3-year moving averages are correct.
| Year | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| 3-year moving average | 9.01 | 10.40 | 2.89 | 9.02 | 10.05 | 17.93 | 15.15 | 14.40 | 7.30 |
(c) Use a calculator with mean and standard deviation keys to verify that for the 3-year moving average, the mean is 10.68% with sample standard deviation 4.53%.
(d) Interpretation Compare the results of parts (a) and (c). Suppose we take the point of view that risk is measured by standard deviation. Is the risk (standard deviation) of the 3-year moving average considerably smaller? This is an example of a general phenomenon that will he studied in more detail in Chapter 6.
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Question 4
An article in Quality Progress (May 2011, pp. 42-48) describes the use of factorial experiments to improve a
silver powder production process. This product is used in conductive pastes to manufacture a wide variety of
products ranging from silicon wafers to elastic membrane switches. Powder density (g/cm²) and surface area
(cm/g) are the two critical characteristics of this product. The experiments involved three factors: reaction
temperature, ammonium percentage, stirring rate. Each of these factors had two levels, and the design was
replicated twice. The design is shown in Table 3.
A222222222222233
Stir Rate
(RPM)
Ammonium
(%)
Table 3: Silver Powder Experiment from Exercise 13.23
Temperature
(°C)
Density
Surface Area
100
8
14.68
0.40
100
8
15.18
0.43
30
100
8
15.12
0.42
30
100
17.48
0.41
150
7.54
0.69
150
8
6.66
0.67
30
150
8
12.46
0.52
30
150
8
12.62
0.36
100
40
10.95
0.58
100
40
17.68
0.43
30
100
40
12.65
0.57
30
100
40
15.96
0.54
150
40
8.03
0.68
150
40
8.84
0.75
30
150…
Chapter 3 Solutions
Bundle: Understanding Basic Statistics, Loose-leaf Version, 8th + WebAssign Printed Access Card, Single-Term
Ch. 3.1 - Statistical Literacy Consider the mode, median,...Ch. 3.1 - Statistical Literacy What symbol is used for the...Ch. 3.1 - Statistical Literacy Look at the formula for the...Ch. 3.1 - Statistical Literacy In order to find the median...Ch. 3.1 - Basic Computation: Mean, Median, Mode Find the...Ch. 3.1 - Basic Computation: Mean, Median, Mode Find the...Ch. 3.1 - Basic Computations Mean, Median, Mode Find the...Ch. 3.1 - Critical Thinking Consider a data set with at...Ch. 3.1 - Critical Thinking Consider a data set with at...Ch. 3.1 - Critical Thinking If a data set has an even number...
Ch. 3.1 - Critical Thinking When a distribution is...Ch. 3.1 - Critical Thinking Consider the following types of...Ch. 3.1 - Critical Thinking Consider the numbers 23455 (a)...Ch. 3.1 - Critical Thinking Consider two data sets. Set...Ch. 3.1 - Interpretation A Job-performance evaluation form...Ch. 3.1 - Critical Thinking: Data Transformation Using...Ch. 3.1 - Critical Thinking: Data Transformation Using...Ch. 3.1 - Critical Thinking Consider a data set of 15...Ch. 3.1 - Environmental Studies: Death Valley How hot does...Ch. 3.1 - Ecology: Wolf Packs How large is a wolf pack? The...Ch. 3.1 - Medical: Injuries The Grand Canyon and the...Ch. 3.1 - Football: Age of Professional Players How old are...Ch. 3.1 - Leisure: Maui Vacation How expensive is Maui? It...Ch. 3.1 - Basic Computation: Weighted Average Find the...Ch. 3.1 - Basic Computation: Weighted Average Find the...Ch. 3.1 - Grades: Weighted Average In your biology class,...Ch. 3.1 - Merit Pay Scale: Weighted Average At General...Ch. 3.1 - EPA: Wetlands Where does all the water go?...Ch. 3.1 - Expand Your knowledge: Harmonic Mean When data...Ch. 3.1 - Expand Your Knowledge: Geometric Mean When data...Ch. 3.2 - Statistical Literacy Which averagemean, median, or...Ch. 3.2 - Statistical Literacy What is the relationship...Ch. 3.2 - Statistical Literacy When computing the standard...Ch. 3.2 - Statistical Literary What symbol is used for the...Ch. 3.2 - Basic Computation: Range, Standard Deviation...Ch. 3.2 - Basic Computation: Range, Standard Deviation...Ch. 3.2 - Critical Thinking Fora given data set in which not...Ch. 3.2 - Critical Thinking Consider two data sets with...Ch. 3.2 - Critical Thinking Each of the following data sets...Ch. 3.2 - Critical Thinking: Data Transformation Using...Ch. 3.2 - Critical Thinking: Data Transformation Using...Ch. 3.2 - Critical Thinking: Outliers One indicator of an...Ch. 3.2 - Basic Computation: Variance, Standard Deviation...Ch. 3.2 - Basic Computation: Coefficient of Variation,...Ch. 3.2 - Basic Computation: Coefficient of Variation....Ch. 3.2 - Investing: Stocks and Bonds Do bonds reduce the...Ch. 3.2 - Space Shuttle: Epoxy Kevlar epoxy it a material...Ch. 3.2 - Archaeology: Ireland The Hill of Tara in Ireland...Ch. 3.2 - Wildlife: Mallard Ducks and Canada Geese For...Ch. 3.2 - Investing: Socially Responsible Mutual Funds Pax...Ch. 3.2 - Medical: Physician Visits In some reports, the...Ch. 3.2 - Grouped Data: Anthropology What was the age...Ch. 3.2 - Grouped Data: Shoplifting What is the age...Ch. 3.2 - Grouped Data: Hours of Sleep per Day Alexander...Ch. 3.2 - Grouped Data: Business Administration What are the...Ch. 3.2 - Expand Your knowledge: Moving Averages You do not...Ch. 3.2 - Prob. 27PCh. 3.2 - Expand Your knowledge: Stratified Sampling and...Ch. 3.2 - Expand Your knowledge: Stratified Sampling and...Ch. 3.2 - Prob. 30PCh. 3.3 - Statistical Literacy Angela took a general...Ch. 3.3 - Statistical Literacy One standard for admission to...Ch. 3.3 - Critical Thinking The town of Butler, Nebraska,...Ch. 3.3 - Critical Thinking Clayton and Timothy took...Ch. 3.3 - Basic Computation: Five-Number Summary,...Ch. 3.3 - Basic Computation: Five-Number Summary...Ch. 3.3 - Health Care: Nurses At Center Hospital there is...Ch. 3.3 - Health Care: Staff Another survey was done at...Ch. 3.3 - Sociology: College Graduates What percentage of...Ch. 3.3 - Sociology: High School Dropouts What percentage of...Ch. 3.3 - Auto Insurance: Interpret GraphsConsumer Reports...Ch. 3.3 - Expand Your knowledge: Outliers Some data include...Ch. 3 - Terminology Consider the following measures of...Ch. 3 - Terminology Consider the statement: For a 5%...Ch. 3 - Terminology When we compute a sample standard...Ch. 3 - Terminology Consider the following terms: outlier,...Ch. 3 - Terminology Consider the following symbols: s,,x,....Ch. 3 - Terminology How is the standard deviation related...Ch. 3 - Terminology In a box-and-whisker plot. which...Ch. 3 - Terminology Consider the following statement: If...Ch. 3 - Statistical Literacy (a) What measures of...Ch. 3 - Critical Thinking Look at the two histograms on...Ch. 3 - Critical Thinking Consider the following Minitab...Ch. 3 - Consumer: Radon Gas "Radon: The Problem No One...Ch. 3 - Political Science: Georgia Democrats How...Ch. 3 - Grade: Weighted Average Professor Cramer...Ch. 3 - General: Average Weight Wright An elevator it...Ch. 3 - Agriculture: Harvest Weight of Maize The following...Ch. 3 - Focus Problem: Water Solve the focus problem at...Ch. 3 - Agriculture: Bell Peppers The pathogen...Ch. 3 - Performance Rating: Weighted Average A performance...Ch. 3 - The Story of Old Faithful is a short book written...Ch. 3 - Most academic advisors tell students to major in a...Ch. 3 - An average is an attempt to summarize a collection...Ch. 3 - Why do we need to study the variation of a...Ch. 3 - Why is the coefficient of variation important?...Ch. 3 - What is Chebyshevs theorem? 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