Stats Exam 1 Correctly Answered 2024.

Stats Exam 1 Correctly Answered 2024. chapter 1 #15 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. (Source: NY Times, Dec. 10, 2006) - CORRECT ANSWER Who—2500 cars; What—Distance from car to bicycle; Population—All cars passing bicyclists. Chapter 1 #25 Babies Medical researchers at a large city hospital investigating the impact of prenatal care on newborn health collected data from 882 births during . 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). - CORRECT ANSWER Who—882 births; Cases—Each of the 882 births is a case; What—Mother's age, length of pregnancy, type of birth, levelof prenatal care, birth weight of baby, sex of baby, and baby's health problems; When—; Where—Large city hospital; Why—Researchers were investigating the impact of prenatal care on newborn health; How—Not specified exactly, but probably from hospital records; Variable—Mother's age; Type—Quantitative; Units—Not specified, probably years; Variable—Length of pregnancy; Type—Quantitative; Units— Weeks; Variable—Birth weight of baby; Type—Quantitative; Units—Not specified, probably pounds and ounces; Variable— Type of birth; Type—Categorical; Variable—Level of prenatal care; Type—Categorical; Variable—Sex; Type—Categorical; Variable—Baby's health problems; Type—Categorical. Chapter 2 #15 Magnet schools An article in the Winter 2003 issue of Chance magazine reported on the Houston Independent School District's magnet schools programs. Of the 1755 qualified applicants, 931 were accepted, 298 were wait-listed, and 526 were turned away for lack of space. Find the relative frequency distribution of the decisions made, and write a sentence describing it. - CORRECT ANSWER 1755 students applied for admission to the magnet schools program. 53% were accepted, 17% were wait-listed, and the other 30% were turned away. Chapter 2 #17 Causes of death 2007 The Centers for Disease Control and Prevention lists causes of death in the United States during 2007: graph pg.36 a) Is it reasonable to conclude that heart or respiratory diseases were the cause of approximately 30.7% of U.S. deaths in 2007? b) What percent of deaths were from causes not listed here? c) Create an appropriate display for these data. - CORRECT ANSWER a) Yes. We can add because these categories do not overlap. (Each person is assigned only one cause of death.) b) 100 - (25.4 + 23.2 + 5.6 + 5.3 + 5.1) = 35.4% c) Either a bar chart or pie chart with "other" added would be appropriate. A bar chart is shown. graph (pg. A-2) Chapter 2 #27 Seniors- Prior to graduation, a high school class was surveyed about its plans. The following table displays the results for white and minority students (the "Minority" group included African-American, Asian, Hispanic, and Native American students): graph pg. 38 a) What percent of the seniors are white? b) What percent of the seniors are planning to attend a 2-year college? c) What percent of the seniors are white and planning to attend a 2-year college? d) What percent of the white seniors are planning to attend a 2-year college?