Problem 2
The processing of raw coal involves washing, in which coal ash (nonorganic, incombustible material) is removed. The article Quantifying Sampling Precision for Coal Ash Using Gys Discrete Model of the Fundamental Error (Journal of Coal Quality, 1989:3339) provides data relating the percentage of ash to the volume of a coal particle. The average percentage of ash for six volumes of coal particles was measured. The data are as follows: Volume (cm3 ) 0.01 0.06 0.58 2.24 15.55 276.02 Percent ash 3.32 4.05 5.69 7.06 8.17 9.36 a. Compute the least-squares line for predicting percent ash (y) from volume (x). Plot the residuals versus the fitted values. Does the linear model seem appropriate? Explain. b. Compute the least-squares line for predicting percent ash from ln volume. Plot the residuals versus the fitted values. Does the linear model seem appropriate? Explain. c. Compute the least-squares line for predicting percent ash from volume. Plot the residuals versus the fitted values. Does the linear model seem appropriate? Explain. d. Using the most appropriate model, predict the percent ash for particles with a volume of 50 m3 . e. Using the most appropriate model, construct a 95% confidence interval for the mean percent ash for particles with a volume of 50 m3 .

Step-by-Step Solution:
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Statistical Inference: provides methods for drawing conclusions about a population from the sample data. There are two ways to do this: Confidence intervals: used to estimate the value of a population parameter using sample statistics Test of Significance: used for assessing evidence for a claim about the population To set up Have to have an SRS...

This full solution covers the following key subjects: . This expansive textbook survival guide covers 153 chapters, and 2440 solutions. The answer to “The processing of raw coal involves washing, in which coal ash (nonorganic, incombustible material) is removed. The article Quantifying Sampling Precision for Coal Ash Using Gys Discrete Model of the Fundamental Error (Journal of Coal Quality, 1989:3339) provides data relating the percentage of ash to the volume of a coal particle. The average percentage of ash for six volumes of coal particles was measured. The data are as follows: Volume (cm3 ) 0.01 0.06 0.58 2.24 15.55 276.02 Percent ash 3.32 4.05 5.69 7.06 8.17 9.36 a. Compute the least-squares line for predicting percent ash (y) from volume (x). Plot the residuals versus the fitted values. Does the linear model seem appropriate? Explain. b. Compute the least-squares line for predicting percent ash from ln volume. Plot the residuals versus the fitted values. Does the linear model seem appropriate? Explain. c. Compute the least-squares line for predicting percent ash from volume. Plot the residuals versus the fitted values. Does the linear model seem appropriate? Explain. d. Using the most appropriate model, predict the percent ash for particles with a volume of 50 m3 . e. Using the most appropriate model, construct a 95% confidence interval for the mean percent ash for particles with a volume of 50 m3 .” is broken down into a number of easy to follow steps, and 208 words. Since the solution to 2 from 7.4 chapter was answered, more than 254 students have viewed the full step-by-step answer. Statistics for Engineers and Scientists was written by and is associated to the ISBN: 9780073401331. The full step-by-step solution to problem: 2 from chapter: 7.4 was answered by , our top Statistics solution expert on 06/28/17, 11:15AM. This textbook survival guide was created for the textbook: Statistics for Engineers and Scientists , edition: 4.