Suppose that different amounts of fertilizer had been used in different fields that were involved in trials of different types of wheat seeds. (a) Explain how the use of different amounts of fertilizer confounds the experimental analysis in the absence of randomization. (b) Considering the regression models with explanatory variables, if the amount of fertilizer were known, how could an analyst adjust for this confounding effect? (a) Choose the correct answer below. O A. Seed variety is highly correlated with fertilizer use. O B. Yield is uncorrelated with fertilizer use. OC. Differences in yield could be due to fertilizer rather than seed variety. O D. Fertilizer use is not uniform for each type of seed. (b) Choose the correct answer below. O A. Add a quantitative explanatory variable for the amount of fertilizer used. O B. Add a categorical explanatory variable for whether fertilizer was used. OC. Add a quantitative explanatory variable for whether fertilizer was used. O D. Add a categorical explanatory variable for the amount of fertilizer used.

Suppose that different amounts of fertilizer had been used in different fields that were involved in trials of different types of wheat seeds. (a) Explain how the use of different amounts of fertilizer confounds the experimental analysis in the absence of randomization. (b) Considering the regression models with explanatory variables, if the amount of fertilizer were known, how could an analyst adjust for this confounding effect? (a) Choose the correct answer below. O A. Seed variety is highly correlated with fertilizer use. O B. Yield is uncorrelated with fertilizer use. OC. Differences in yield could be due to fertilizer rather than seed variety. O D. Fertilizer use is not uniform for each type of seed. (b) Choose the correct answer below. O A. Add a quantitative explanatory variable for the amount of fertilizer used. O B. Add a categorical explanatory variable for whether fertilizer was used. OC. Add a quantitative explanatory variable for whether fertilizer was used. O D. Add a categorical explanatory variable for the amount of fertilizer used.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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