Problem regarding the different amounts of fertilizer

Reference no: EM131009233

Suppose that different amounts of fertilizer had been used in different fields that were involved in the wheat trials.

(a) Explain how the use of different amounts of fertilizer confounds the experimental analysis in the absence of randomization.

(b) Considering regression models if the amounts of fertilizer were known, how could an analyst adjust for this confounding effect?

Reference no: EM131009233

Questions Cloud

Why does apple sit at the top of both lists : Why does Apple sit at the top of both lists? How has the company used good branding and positioning strategy to achieve this result

Problem regarding the preferences of consumers : Assuming that the data meet the required condi- tions, what can we conclude from the F-test about the preferences of consumers?

What was the firms operating cash flow during 2014 : The December 31, 2013, balance sheet of Schism, Inc., showed long-term debt of $1,465,000, $153,000 in the common stock account and $2,780,000 in the additional paid-in surplus account. What was the firm's operating cash flow during 2014?

Producing a numerical score called gullible : As part of the study underlying Example 1, each customer took a test that measures willingness to believe claims, producing a numerical score called Gullible. If the customers had not been randomly assigned, an analyst planned to fit the regressio..

Problem regarding the different amounts of fertilizer : Suppose that different amounts of fertilizer had been used in different fields that were involved in the wheat trials. (a) Explain how the use of different amounts of fertilizer confounds the experimental analysis in the absence of randomization.

Accuracy of the estimated mean of the first group : The 95% confidence interval for m derived from a sample of n observations from a normal population gets smaller as the sample size increases because the standard error of the mean s> 1n decreases. Adding more groups to an ANOVA also increases n. (..

Find the length of the curve : Find the length of the curve x=((y3)/3)+(1/(4y)) from y=1 to y=4. Find the length of the curve at x=((y3)/6)+(1/(2y)) on 3 less than or equal to y less than or equal to 5.

Explanatory variables in the regression : How many dummy variables would be needed as explanatory variables in the regression? Suppose that se = 4.217 bushels per acre, as in the text analysis of five varieties. With so much more data, are the Tukey and Bonferroni confidence intervals for ..

What types of strategies they using to reach target market : What types of strategies are they using to reach this target market, and what strategies can you recommend in the future? In the interest of maintaining diversity within the discussion forum, please select a company that has not yet been discussed b..

User Account

All Pages