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Oil content of fried sweet potato chips. The characteristics of sweet potato chips fried at different temperatures were investigated in the Journal of Food Engineering (September 2013). A sample of 6 sweet potato slices were fried at 130° using a vacuum fryer. One characteristic of interest to the researchers was internal oil content (measured in millions of grams). The results were:
- a. Identify the target parameter, in symbols and words.
- b. Compute a 95% confidence interval for σ2.
- c. What does it mean to say that the target parameter lies within the interval with “95% confidence”?
- d. What assumption about the data must be satisfied in order for the confidence interval to be valid?
- e. To obtain a practical interpretation of the interval, part b, explain why a confidence interval for the standard deviation, σ, is desired.
- f. Use the results, part b, to compute a 95% confidence interval for σ. Give a practical interpretation of the interval.
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Chapter 6 Solutions
Statistics for Business and Economics Plus MyLab Statistics with Pearson eText -- Title-Specific Access Card Package (13th Edition)
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