Questions from Applied Statistics


Q: Choose either 2 × 2 contingency table shown below (males or

Choose either 2 × 2 contingency table shown below (males or females). Research question: At α = .005, is smoking independent of race? (Smoking rates are from Statistical Abs...

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Q: High levels of cockpit noise in an aircraft can damage the hearing

High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld sound...

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Q: Forecasters’ interest rate predictions over an eight-year period were studied

Forecasters’ interest rate predictions over an eight-year period were studied to see whether the predictions corresponded to what actually happened. The 2 × 2 contingenc...

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Q: In a study of childhood asthma, 4,317 observations were

In a study of childhood asthma, 4,317 observations were collected on education and smoking during pregnancy, shown in the 4 × 3 contingency table below. Research question: At Î&plus...

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Q: Two contingency tables below show return on investment (ROI) and

Two contingency tables below show return on investment (ROI) and percent of sales growth over the previous 5 years for 85 U.S. firms. ROI is defined as percentage of return on a combination of stockho...

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Q: Based on the cost of sampling and the presumed accuracy required,

Based on the cost of sampling and the presumed accuracy required, would sampling or 100 percent inspection be used to collect data on (a) the horsepower of each engine being installed in new cars; (b)...

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Q: Bob said, “We use the normal distribution to set the

Bob said, “We use the normal distribution to set the control limits for the  chart because samples from processes follow a normal distribution.” Is Bob right? Explain.

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Q: (a) Make a scatter plot of the data. What

(a) Make a scatter plot of the data. What does it suggest about the correlation between X and Y? (b) Use Excel, MegaStat, or MINITAB to calculate the correlation coefficient. (c) Use Excel or Appendi...

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Q: In the following regression, X = weekly pay, Y =

In the following regression, X = weekly pay, Y = income tax withheld, and n = 35 McDonald’s employees. (a) Write the fitted regression equation. (b) State the degrees of freedom for...

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Q: Does your sample size fulfill Evans’ Rule (n/k >

Does your sample size fulfill Evans’ Rule (n/k > 10) or at least Doane’s Rule (n/k > 5)?

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