Questions from Applied Statistics


Q: (a) Plot the data on law enforcement officers killed.

(a) Plot the data on law enforcement officers killed. (b) Describe the trend (if any) and discuss possible causes or anomalies in the data. (c) Would a fitted trend be helpful? Explain. (c) Make a for...

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Q: Salaries of 30 randomly chosen individuals in the same occupation (only

Salaries of 30 randomly chosen individuals in the same occupation (only the first 3 and last 3 observations are shown). The data are from a salary equity study comparing two industries. Research quest...

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Q: Does a class break stimulate the pulse? Here are heart rates

Does a class break stimulate the pulse? Here are heart rates for a sample of 30 students before and after a class break. Research question: At α = .05, do the medians differ?

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Q: Do a two-tailed t test for zero slope for each

Do a two-tailed t test for zero slope for each predictor coefficient at α = .05. State the degrees of freedom and look up the critical value in Appendix D (or from Excel). Appendix D:...

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Q: (a) Plot both men’s and women’s winning times on the

(a) Plot both men’s and women’s winning times on the same graph. (b) Fit a linear trend model to each series (men, women). (c) Use Excel’s option...

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Q: (a) Plot U.S. petroleum imports on a

(a) Plot U.S. petroleum imports on a graph. (b) Describe the trend (if any) and discuss possible causes. (c) Fit both a linear and an exponential trend. (c) Interpret each fitted trend equation, expla...

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Q: (a) Which p-values indicate predictor significance at α

(a) Which p-values indicate predictor significance at α = .05? (b) Do the p-values support the conclusions you reached from the t tests? (c) Do you prefer the t test or the p-value appro...

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Q: Based on the R2 and ANOVA table for your model, how

Based on the R2 and ANOVA table for your model, how would you describe the fit?

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Q: Use Excel’s Add Trendline feature to fit a linear regression to the

Use Excel’s Add Trendline feature to fit a linear regression to the scatter plot. Is a linear model credible? Midterm and Final Exam Scores for Business Statistics Students Fall Se...

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Q: Use the standard error to construct an approximate prediction interval for Y

Use the standard error to construct an approximate prediction interval for Y. Based on the width of this prediction interval, would you say the predictions are good enough to have practical value?...

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