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For the situations described. (a) What are the cases? (b) What is the variable and is it quantitative or categorical? People in a city are asked if they support a new recycling law.

For the situations described. (a) What are the cases? (b) What is the variable and is it quantitative or categorical? Record the percentage change in the price of a stock for 100 stocks publicly traded on Wall Street.

For the situations described. (a) What are the cases? (b) What is the variable and is it quantitative or categorical? Collect data from a sample of teenagers with a question that asks "Do you eat at least five servings a day of fruits and vegetables?"

For the situations described. (a) What are the cases? (b) What is the variable and is it quantitative or categorical? Measure the shelf life of bunches of bananas (the number of days until the bananas go bad) for a large sample.

A relationship between two variables is described. In each case, we can think of one variable as helping to explain the other. Identify the explanatory variable and the response variable. Amount of fertilizer used and the yield of a crop

Student Survey Variables Data 1.1 introduced the dataset StudentSurvey, and Example 1.2 identified seven of the variables in that dataset as categorical or quantitative. The remaining variables are: MathSAT \(\quad\) Score on the Math section of the SAT exam SAT \(\quad\) Sum of the scores on the Verbal and Math sections of the SAT exam HigherSAT Which is higher, Math SAT score or Verbal SAT score? (a) Indicate whether each variable is quantitative or categorical. (b) List at least two questions we might ask about any one of these individual variables. (c) List at least two questions we might ask about relationships between any two (or more) of these variables.

Spiders regularly engage in spider foreplay that does not culminate in mating. Male spiders mature faster than female spiders and often practice the mating routine on not-yet-mature females. Since male spiders run the risk of getting eaten by female spiders, biologists wondered why spiders engage in this behavior. In one study, some spiders were allowed to participate in these near-matings, while other maturing spiders were isolated. When the spiders were fully mature, the scientists observed real matings. They discovered that if either partner had participated at least once in mock sex, the pair reached the point of real mating significantly faster than inexperienced spiders did. (Mating faster is, apparently, a real advantage in the spider world.) Describe the variables, indicate whether each variable is quantitative or categorical, and indicate the explanatory and response variables.

When women take birth control pills, some of the hormones found in the pills eventually make their way into lakes and waterways. In one study, a water sample was taken from various lakes. The data indicate that as the concentration of estrogen in the lake water goes up, the fertility level of fish in the lake goes down. The estrogen level is measured in parts per trillion (ppt) and the fertility level is recorded as the percent of eggs fertilized. What are the cases in this study? What are the variables? Classify each variable as either categorical or quantitative.

Example 1.5 studied a variant of the gene \(A C T N 3\) which inhibits fast- twitch muscles and seems to be less prevalent in sprinters. A separate study \(^{9}\) indicated ethnic differences: Approximately \(20 \%\) of a sample of Caucasians, approximately \(25 \%\) of a sample of Asians, and approximately \(1 \%\) of a sample of Africans had the gene variant. What are the variables in this study? Classify each as categorical or quantitative.

On January \(14,2012,\) Andrew Brown of Great Britain set the world record time ( 40 days) for rowing solo across the northern Atlantic Ocean. On March 14 , 2010, Katie Spotz of the United States became the youngest person to ever row solo across the Atlantic when she completed it in 70 days at the age of 22 years old. Table 1.3 shows times for males and females who rowed solo across the Atlantic Ocean in the last few years. \(^{10}\) (a) How many cases are there in this dataset? How many variables are there and what are they? Is each categorical or quantitative? (b) Display the information in Table 1.3 as a dataset with cases as rows and variables as columns. $$ \begin{array}{ll} \hline \text { Male times: } & 40,87,78,106,67 \\ \text { Female times: } & 70,153,81 \\ \hline \end{array} $$