Statistics for Engineers and Scientists
4th Edition
ISBN: 9780073530789
Author: Navidi
Publisher: MCG
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Textbook Question
Chapter 1.3, Problem 4E
Following are measurements of soil concentrations (in mg/kg) of chromium (Cr) and nickel (Ni) at 20 sites in the area of Cleveland, Ohio. These data are taken from the article “Variation in North American Regulatory Guidance for Heavy Metal Surface Soil Contamination at Commercial and Industrial Sites” (A. Jennings and J. Ma, J Environment Eng, 2007:587–609).
Cr: 34 1 511 2 574 496 322 424
269 140 244 252 76 108 24 38
18 34 30 191
Ni: 23 22 55 39 283 34 159 37
61 34 163 140 32 23 54 837
64 354 376 471
- a. Construct a histogram for each set of concentrations.
- b. Construct comparative boxplots for the two sets of concentrations.
- c. Using the boxplots, what differences can be seen between the two sets of concentrations?
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Following are measurements of soil concentrations (in mg /kg) of chromium (Cr) and nickel (Ni) at20 sites in the area of Cleveland, Ohio. These data are taken from the article "Variation in NorthAmerican Regulatory Guidance for Heavy Metal Surface Soil Contamination at Commercial andIndustrial Sites" (A. Jennings and J. Ma, J. Environment Eng, 2007:587-609).
Cr: 260 19 36 247 263 319 317 277 319 264 23 29 61 119 33 281 21 35 64 30Ni: 435 377 359 53 38 38 54 188 397 33 92 490 28 35 799 347 321 32 74 508
(a) Construct a histogram for each set of concentrations.
(b) Find the 1st, 2nd and 3rd quartiles for the Cr concentrations
(c) Find the 1st, 2nd and 3rd quartiles for the Ni concentrations.
Following are measurements of soil concentrations (in mg /kg) of chromium (Cr) and nickel (Ni) at20 sites in the area of Cleveland, Ohio. These data are taken from the article "Variation in NorthAmerican Regulatory Guidance for Heavy Metal Surface Soil Contamination at Commercial andIndustrial Sites" (A. Jennings and J. Ma, J. Environment Eng, 2007:587-609).Cr: 260 19 36 247 263 319 317 277 319 264 23 29 61 119 33 281 21 35 64 30Ni: 435 377 359 53 38 38 54 188 397 33 92 490 28 35 799 347 321 32 74 508
(d) Use these to construct comparative boxplots for the two sets of concentrations.
(e) Using the boxplots, what differences can be seen between the two sets of concentrations?
The article “Hydrogeochemical Characteristics of Groundwater in a Mid-Western CoastalAquifer System” (S. Jeen, J. Kim, et al., Geosciences Journal, 2001:339–348) presentsmeasurements of various properties of shallow groundwater in a certain aquifer system inKorea. Following are measurements of electrical conductivity (in microsiemens percentimeter) for 23 water samples.2099 528 2030 1350 1018 384 14991265 375 424 789 810 522 513488 200 215 486 257 557 260461 500Find the mean.Find the standard deviation.Find the median.Construct a dotplot.Find the 10% trimmed mean.Find the first quartile.Find the third quartile.Find the interquartile range.Construct a boxplot.Which of the points, if any, are outliers?If a histogram were constructed, would it be skewed to the left, skewed to the right, orapproximately symmetric?
Chapter 1 Solutions
Statistics for Engineers and Scientists
Ch. 1.1 - Each of the following processes involves sampling...Ch. 1.1 - If you wanted to estimate the mean height of all...Ch. 1.1 - True or false: a. A simple random sample is...Ch. 1.1 - A sample of 100 college students is selected from...Ch. 1.1 - A certain process for manufacturing integrated...Ch. 1.1 - Refer to Exercise 5. True or false: a. If the...Ch. 1.1 - To determine whether a sample should be treated as...Ch. 1.1 - A medical researcher wants to determine whether...Ch. 1.1 - A medical researcher wants to determine whether...Ch. 1.2 - True or false: For any list of numbers, half of...
Ch. 1.2 - Is the sample mean always the most frequently...Ch. 1.2 - Is the sample mean always equal to one of the...Ch. 1.2 - Is the sample median always equal to one of the...Ch. 1.2 - Find a sample size for which the median will...Ch. 1.2 - For a list of positive numbers, is it possible for...Ch. 1.2 - Is it possible for the standard deviation of a...Ch. 1.2 - In a certain company, every worker received a...Ch. 1.2 - In another company, every worker received a 5%...Ch. 1.2 - A sample of 100 adult women was taken, and each...Ch. 1.2 - In a sample of 20 men, the mean height was 178 cm....Ch. 1.2 - Each of 16 students measured the circumference of...Ch. 1.2 - Refer to Exercise 12. a. If the measurements for...Ch. 1.2 - There are 10 employees in a particular division of...Ch. 1.2 - Quartiles divide a sample into four nearly equal...Ch. 1.2 - In each of the following data sets, tell whether...Ch. 1.3 - The weather in Los Angeles is dry most of the...Ch. 1.3 - Forty-five specimens of a certain type of powder...Ch. 1.3 - Refer to Table 1.2 (in Section 1.2). Construct a...Ch. 1.3 - Following are measurements of soil concentrations...Ch. 1.3 - A certain reaction was run several times using...Ch. 1.3 - Sketch a histogram for which a. The mean is...Ch. 1.3 - The figure below is a histogram showing the...Ch. 1.3 - The histogram below presents the compressive...Ch. 1.3 - Refer to Table 1.4 (in Section 1.3). a. Using the...Ch. 1.3 - Refer to Table 1.5 (in Section 1.3). a. Using the...Ch. 1.3 - The following table presents the number of...Ch. 1.3 - Which of the following statistics cannot be...Ch. 1.3 - A sample of 100 resistors has an average...Ch. 1.3 - Following are boxplots comparing the amount of...Ch. 1.3 - Following are summary statistics for two data...Ch. 1.3 - Match each histogram to the box plot that...Ch. 1.3 - Prob. 17ECh. 1.3 - Match each scatterplot to the statement that best...Ch. 1.3 - Prob. 19ECh. 1 - A vendor converts the weights on the packages she...Ch. 1 - Refer to Exercise 1. The vendor begins using...Ch. 1 - The specification for the pull strength of a wire...Ch. 1 - A coin is tossed twice and comes up heads both...Ch. 1 - The smallest number on a list is changed from 12.9...Ch. 1 - There are 15 numbers on a list, and the smallest...Ch. 1 - There are 15 numbers on a list, and the mean is...Ch. 1 - The article The Selection of Yeast Strains for the...Ch. 1 - Concerning the data represented in the following...Ch. 1 - True or false: In any boxplot, a. The length of...Ch. 1 - For each of the following histograms, determine...Ch. 1 - In the article Occurrence and Distribution of...Ch. 1 - The article Vehicle-Arrival Characteristics at...Ch. 1 - The cumulative frequency and the cumulative...Ch. 1 - The article Hydrogeochemical Characteristics of...Ch. 1 - Water scarcity has traditionally been a major...Ch. 1 - Prob. 18SECh. 1 - The article The Ball-on-Three-Ball Test for...
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