Job hunting A June 2011 Gallup Poll asked Americans,

Problem 1E Grocery shopping Many grocery store chains offer customers a card they can scan when they check out and offer discounts to people who do so. To get the card, customers must give information, including a mailing address and e-mail address. The actual purpose is not to reward loyal customers but to gather data. What data do these cards allow stores to gather, and why would they want that data?

Problem 2E Online shopping Online retailers such as Amazon.com keep data on products that customers buy, and even products they look at. What does Amazon hope to gain from such information?

Problem 3E Super Bowl Sports announcers love to quote statistics. During the Super Bowl, they particularly love to announce when a record has been broken. They might have a list of all Super Bowl games, along with the scores of each team, total scores for the two teams, margin of victory, passing yards for the quarterbacks, and many more bits of information. Identify the who in this list.

Problem 4E Nobel laureates The website www.nobelprize.org allows you to look up all the Nobel prizes awarded in any year. The data are not listed in a table. Rather you drag a slider to the year and see a list of the awardees for that year. Describe the who in this scenario.

Problem 6E ZIP codes The Postal Service uses five-digit ZIP codes to identify locations to assist in delivering mail. a) In what sense are ZIP codes categorical? b) Is there any ordinal sense to ZIP codes? In other words, does a larger ZIP code tell you anything about a location compared to a smaller ZIP code?

Problem 8E Job hunting A June 2011 Gallup Poll asked Americans, “Thinking about the job situation in America today, would you say that it is now a good time or a bad time to find a quality jobs?” The choices were “Good time” or “Bad time”. What kind of variable is the response?

Medicine A pharmaceutical company conducts an experiment in which a subject takes 100 mg of a substance orally. The researchers measure how many minutes it takes for half of the substance to exit the bloodstream. What kind of variable is the company studying?

Problem 7E Voters A February 2010 Gallup Poll question asked, “In politics, as of today, do you consider yourself a Republican, a Democrat, or an Independent?” The possible responses were “Democrat”, “Republican”, “Independent”, “Other”, and “No Response”. What kind of variable is the response?

Problem 5E Grade levels A person’s grade in school is generally identified by a number. a) Give an example of a why in which grade level is treated as categorical. b) Give an example of a why in which grade level is treated as quantitative.

Stress A medical researcher measures the increase in heart rate of patients under a stress test. What kind of variable is the researcher studying?

Problem 13E For each description of data, identify Who and What were investigated and the population of interest Gaydar A study conducted by a team of American and Canadian researchers found that during ovulation, a woman can tell whether a man is gay or straight by looking at his face. To explore the subject, the authors conducted three investigations, the first of which involved 40 undergraduate women who were asked to guess the sexual orientation of 80 men based on photos of their face. Half of the men were gay, and the other half were straight. All held similar expressions in the photos or were deemed to be equally attractive. None of the women were using any contraceptive drugs at the time of the test. The result: the closer a woman was to her peak ovulation the more accurate her guess. (Source: news.yahoo.com/does-ovulation-boost-womansgaydar-210405621.html)

Problem 15E For each description of data, identify Who and What were investigated and the population of interest Bicycle safety Ian Walker, a psychologist at the University of Bath, wondered whether drivers treat bicycle riders differently when they wear helmets. He rigged his bicycle with an ultrasonic sensor that could measure how close each car was that passed him. He then rode on alternating days with and without a helmet. Out of 2500 cars passing him, he found that when he wore his helmet, motorists passed 3.35 inches closer to him, on average, than when his head was bare. [NY Times, Dec. 10, 2006]

Problem 16E For each description of data, identify Who and What were investigated and the population of interest Investments Some companies offer 401(k) retirement plans to employees, permitting them to shift part of their before-tax salaries into investments such as mutual funds. Employers typically match 50% of the employees’ contribution up to about 6% of salary. One company, concerned with what it believed was a low employee participation rate in its 401(k) plan, sampled 30 other companies with similar plans and asked for their 401(k) participation rates.

For each description of data, identify Who and What were investigated and the Population of interest. Hula-hoops The hula-hoop, a popular children’s toy in the 1950s, has gained popularity as an exercise in recent years. But does it work? To answer this question, the American Council on Exercise conducted a study to evaluate the cardio and calorie-burning benefits of “hooping.” Researchers recorded heart rate and oxygen consumption of participants, as well as their individual ratings of perceived exertion, at regular intervals during a 30-minute workout. (www.acefitness.org/certifiednewsarticle/1094/)

For each description of data, identify Who and What were investigated and the Population of interest. Honesty Coffee stations in offices often just ask users to leave money in a tray to pay for their coffee, but many people cheat. Researchers at Newcastle University alternately taped two posters over the coffee station. During one week, it was a picture of flowers; during the other, it was a pair of staring eyes. They found that the average contribution was significantly higher when the eyes poster was up than when the flowers were there. Apparently, the mere feeling of being watched—even by eyes that were not real—was enough to encourage people to behave more honestly. (Source: NY Times, Dec. 10, 2006)

For each description of data, identify Who and What were investigated and the Population of interest. Blindness A study begun in 2011 examines the use of stem cells in treating two forms of osteopenia. Each of the 24 patients entered one of two separate trials in which embryonic stem cells were to be used to treat the condition.

Problem 19E For each description of data, identify Who and What were investigated and the Population of interest. Not-so-diet soda A look at 474 participants in the San Antonio Longitudinal Study of Aging found that participants who drank two or more diet sodas a day “experienced waist size increases six times greater than those of people who didn’t drink diet soda.” (news.yahoo.com/ diet-sodas-dont-help-dieting-175007737.html)

Problem 21E For each description of data, identify the W’s, name the variables, specify for each variable whether its use indicates that it should be treated as categorical or quantitative, and, for any quantitative variable, identify the units in which it was measured (or note that they were not provided). Weighing bears Because of the difficulty of weighing a bear in the woods, researchers caught and measured 54 bears, recording their weight, neck size, length, and sex. They hoped to find a way to estimate weight from the other, more easily determined quantities.

For each description of data, identify the W’s, name the variables, specify for each variable whether its use indicates that it should be treated as categorical or quantitative, and, for any quantitative variable, identify the units in which it was measured (or note that they were not provided). Age and party The Gallup Poll conducted a representative telephone survey of 1180 American voters during the first quarter of 2007. Among the reported results were the voter’s region (Northeast, South, etc.), age, party affiliation, and whether or not the person had voted in the 2006 midterm congressional election.

Problem 20E For each description of data, identify Who and What were investigated and the population of interest Molten iron The Cleveland Casting Plant is a large, highly automated producer of gray and nodular iron automotive castings for Ford Motor Company. The company is interested in keeping the pouring temperature of the molten iron (in degrees Fahrenheit) close to the specified value of 2550 degrees. Cleveland Casting measured the pouring temperature for 10 randomly selected crankshafts.

Problem 22E For each description of data, identify the W’s, name the variables, specify for each variable whether its use indicates that it should be treated as categorical or quantitative, and, for any quantitative variable, identify the units in which it was measured (or note that they were not provided). Schools The State Education Department requires local school districts to keep these records on all students: age, race or ethnicity, days absent, current grade level, standardized test scores in reading and mathematics, and any disabilities or special educational needs.

Problem 23E For each description of data, identify the W’s, name the variables, specify for each variable whether its use indicates that it should be treated as categorical or quantitative, and, for any quantitative variable, identify the units in which it was measured (or note that they were not provided). Arby’s menu A listing posted by the Arby’s restaurant chain gives, for each of the sandwiches it sells, the type of meat in the sandwich, the number of calories, and the serving size in ounces. The data might be used to assess the nutritional value of the different sandwiches.

Problem 27E For each description of data, identify the W’s, name the variables, specify for each variable whether its use indicates that it should be treated as categorical or quantitative, and, for any quantitative variable, identify the units in which it was measured (or note that they were not provided). Herbal medicine Scientists at a major pharmaceutical firm conducted an experiment to study the effectiveness of an herbal compound to treat the common cold. They exposed each patient to a cold virus, then gave them either the herbal compound or a sugar solution known to have no effect on colds. Several days later they assessed each patient’s condition, using a cold severity scale ranging from 0 to 5. They found no evidence of the benefits of the compound.

Problem 26E For each description of data, identify the W’s, name the variables, specify for each variable whether its use indicates that it should be treated as categorical or quantitative, and, for any quantitative variable, identify the units in which it was measured (or note that they were not provided). Flowers In a study appearing in the journal Science, a research team reports that plants in southern England are flowering earlier in the spring. Records of the first flowering dates for 385 species over a period of 47 years show that flowering has advanced an average of 15 days per decade, an indication of climate warming, according to the authors.

Problem 25E For each description of data, identify the W’s, name the variables, specify for each variable whether its use indicates that it should be treated as categorical or quantitative, and, for any quantitative variable, identify the units in which it was measured (or note that they were not provided). Babies Medical researchers at a large city hospital investigating the impact of prenatal care on newborn health collected data from 882 births during 1998–2000. They kept track of the mother’s age, the number of weeks the pregnancy lasted, the type of birth (cesarean, induced, natural), the level of prenatal care the mother had (none, minimal, adequate), the birth weight and sex of the baby, and whether the baby exhibited health problems (none, minor, major).

Problem 29E For each description of data, identify the W’s, name the variables, specify for each variable whether its use indicates that it should be treated as categorical or quantitative, and, for any quantitative variable, identify the units in which it was measured (or note that they were not provided). Streams In performing research for an ecology class, students at a college in upstate New York collect data on local streams each year. They record a number of biological, chemical, and physical variables, including the stream name, the substrate of the stream (limestone, shale, or mixed), the acidity of the water (pH), the temperature (°C), and the BCI (a numerical measure of biological diversity).

Problem 28E For each description of data, identify the W’s, name the variables, specify for each variable whether its use indicates that it should be treated as categorical or quantitative, and, for any quantitative variable, identify the units in which it was measured (or note that they were not provided). Vineyards Business analysts hoping to provide information helpful to American grape growers compiled these data about vineyards: size (acres), number of years in existence, state, varieties of grapes grown, average case price, gross sales, and percent profit.

Problem 32E Walking in circles People who get lost in the desert, mountains, or woods often seem to wander in circles rather than walk in straight lines. To see whether people naturally walk in circles in the absence of visual clues, researcher Andrea Axtell tested 32 people on a football field. One at a time, they stood at the center of one goal line, were blindfolded, and then tried to walk to the other goal line. She recorded each individual’s sex, height, handedness, the number of yards each was able to walk before going out of bounds, and whether each wandered off course to the left or the right. No one made it all the way to the far end of the field without crossing one of the sidelines. [STATS No. 39, Winter 2004]

Problem 30E For each description of data, identify the W’s, name the variables, specify for each variable whether its use indicates that it should be treated as categorical or quantitative, and, for any quantitative variable, identify the units in which it was measured (or note that they were not provided). Fuel economy The Environmental Protection Agency (EPA) tracks fuel economy of automobiles based on information from the manufacturers (Ford, Toyota, etc.). Among the data the agency collects are the manufacturer, vehicle type (car, SUV, etc.), weight, horsepower, and gas mileage (mpg) for city and highway driving.