Essentials Of Statistics For The Behavioral Sciences
9th Edition
ISBN: 9781337273312
Author: GRAVETTER, Frederick J., Wallnau, Larry B., Forzano, Lori-ann B.
Publisher: Cengage Learning,
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Textbook Question
Chapter 4, Problem 22P
The
- a. Compute the range (choose either definition), the variance, and the standard deviation for the following sample of n = 4 scores. Note that there are two scores located in the center of the distribution and two extreme values. Scores: 0, 6, 6, 12
- b. Now we will increase the variability by moving the two central scores out to the extremes. Once again compute the range, the variance, and the standard deviation. New scores: 0, 0, 12, 12
- c. According to the range, how do the two distributions compare in variability? How do they compare according to the variance and standard deviation?
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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 4 Solutions
Essentials Of Statistics For The Behavioral Sciences
Ch. 4.1 - Which of the following is a consequence of...Ch. 4.1 - What is the range for the following set of scores?...Ch. 4.1 - For the following scores, which of the following...Ch. 4.2 - Which of the following sets of scores has the...Ch. 4.2 - What is the variance for the following set of...Ch. 4.2 - A set of scores ranges from a high of X = 24 to a...Ch. 4.3 - What is SS, the sum of the squared deviations, for...Ch. 4.3 - What is the standard deviation for the following...Ch. 4.3 - Prob. 3LCCh. 4.4 - Which of the following explains why it is...
Ch. 4.4 - Under what circumstances is the computational...Ch. 4.4 - Prob. 3LCCh. 4.5 - A researcher takes a sample from a population and...Ch. 4.5 - A researcher takes all of the possible samples of...Ch. 4.5 - All the possible samples of n = 3 scores are...Ch. 4.6 - If a normal-shaped population with y. 40 and o 5...Ch. 4.6 - If 5 points are added to every score in a...Ch. 4.6 - A research study obtains a mean of 12.7 and a...Ch. 4.6 - For which of the following distributions would X =...Ch. 4 - Briefly explain the goal for defining and...Ch. 4 - What is the range for the following set of scores?...Ch. 4 - In words, explain what is measured by variance and...Ch. 4 - Is it possible to obtain a negative value for...Ch. 4 - Describe the scores in a sample that has a...Ch. 4 - There are two different formulas or methods that...Ch. 4 - Calculate the mean and SS (sum of squared...Ch. 4 - For the following population of N = 9 scores: 4,...Ch. 4 - Calculate SS, variance, and standard deviation for...Ch. 4 - Calculate SS. variance, and standard deviation for...Ch. 4 - Calculate SS. variance, and standard deviation for...Ch. 4 - For the following set of scores; 6, 2, 3, 0, 4 a....Ch. 4 - Explain why the formula for sample variance is...Ch. 4 - For the following sample or n = 6 scores: 0, 11,...Ch. 4 - Calculate SS, variance, and standard deviation for...Ch. 4 - Calculate SS, variance, and standard deviation for...Ch. 4 - A population has a mean of = 50 and a standard...Ch. 4 - Solve the following problems. a. After 6 points...Ch. 4 - Compute the mean and standard deviation for the...Ch. 4 - For the following sample of n = 8 scores: 0, 1,12,...Ch. 4 - For the following population of N = 6 scores: 2,...Ch. 4 - The range is completely determined by the two...Ch. 4 - For the data in the following sample: 1, 1, 9, 1...Ch. 4 - Arden and Plomin (2006) published a study...Ch. 4 - A population has a mean of = 50 and a standard...Ch. 4 - On an exam with a mean of M = 39, you obtain a...
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