[DATA] Hurricanes [See Problem 14 in Section 12.3] The following data represent the maximum wind speed (in knots) and atmospheric pressure (in millibars) for a random sample of hurricanes that originated in the Atlantic Ocean.

c. Use the “Randomization test for slope” applet in StatCrunch to build the null model to generate at least 2000 repetitions of this study to obtain a P-value. Interpret the P-value.

[DATA] Age versus HDL Cholesterol A doctor wanted to determine whether there is a relation between a male’s age and his HDL (so-called good) cholesterol. He randomly selected 17 of his patients and determined their HDL levels. He obtained the following data.

b. Determine the least-squares regression equation from the sample data.

The output shown was obtained from Minitab.

a. The least-squares regression equation is y^ = 1.3962x + 12.396. What is the predicted value of y at x = 10?

The output shown was obtained from Minitab.

c. The standard error, se, is 2.167. What is an estimate of the standard deviation of y at x=10?

[DATA] Height versus Head Circumference [See Problem 13 in Section 12.3] A pediatrician wants to determine the relation that may exist between a child’s height and head circumference. She randomly selects 11 children from her practice, measures their heights and head circumferences, and obtains the following data:

d. State your conclusion to the hypotheses from part (b).

[DATA] Concrete [See Problem 15 in Section 12.3] As concrete cures, it gains strength. The following data represent the 7-day and 28-day strength (in pounds per square inch) of a certain type of concrete:

b. Suppose a researcher wanted to determine if there is a linear relation between 7-day strength and 28-day strength. What would be the null and alternative hypotheses?

[DATA] Concrete [See Problem 15 in Section 12.3] As concrete cures, it gains strength. The following data represent the 7-day and 28-day strength (in pounds per square inch) of a certain type of concrete:

d. State your conclusion to the hypotheses from part (b).

[DATA] CEO Performance [See Problem 19 in Section 12.3] The following data represent the total compensation for 12 randomly selected chief executive officers (CEOs) and the company’s stock performance in 2017.

b. Suppose a researcher wanted to determine if there is a linear relation between compensation and stock return. What would be the null and alternative hypotheses?

[DATA] Bear Markets [See Problem 20 in Section 12.3] A bear market is a market condition in which the price of the security falls. A bear market in the stock market is defined as a condition in which market declines by 20% or more over the course of at least two months. The following data represent the number of months and percentage change in the S&P500 (a group of 500 stocks).

b. Suppose a researcher wanted to determine if there is a linear relation between months and percent change. What would be the null and alternative hypotheses?