Exam (elaborations) MATH 302 STATISTICS

Part 1 of 5 - Section: Data & Sampling 4.0/ 5.0 Points Question 1 of 20 1.0/ 1.0 Points “Number of times per week” is what type of data in the scenario? A study was done to determine the age, the number of times per week, and the duration (amount of time) of residents using a local gym in San Antonio, Texas. The first car in the parking lot was selected randomly, and then the resident of every eighth car in the lot around the gym was interviewed. • A. Qualitative • B. Quantitative Discrete • C. Quantitative Continuous Answer Key: B Question 2 of 20 1.0/ 1.0 Points An Excel generates 200 random numbers, and 200 people whose names correspond with the numbers on the list are chosen. What type of sampling was used? • A. Convenience • B. Systematic • C. Simple Random • D. Stratified • E. Cluster Answer Key: C Question 3 of 20 0.0/ 1.0 Points What is the sampling method used in the following scenario? The barista at a local Starbucks wants to determine what proportion of the coffee users are teenagers. The barista has a tally sheet on which she marks whether the coffee order is for a teenager or adult. She records this data for every fifth patron who orders coffee. • A. systematic • B. cluster • C. convenience • D. stratified • E. simple random Answer Key: A Question 4 of 20 1.0/ 1.0 Points A market researcher polled every eighth person who walks into a grocery store. What type of sampling was used? • A. Cluster • B. Stratified • C. Simple Random • D. Systematic • E. Convenience Answer Key: D Question 5 of 20 1.0/ 1.0 Points The first 65 people who walk into a sports bar are polled on their television preferences. What type of sampling was used? • A. Convenience • B. Systematic • C. Stratified • D. Cluster Answer Key: A Part 2 of 5 - Section: Statistics, Probability and Key Terms 5.0/ 5.0 Points Question 6 of 20 1.0/ 1.0 Points A local polling chapter is interested in the mean age of people who voted in the last election. They want to use this information to help get more people of all ages out to vote. Identify the sample. • A. the population mean age of people who voted • B. a subgroup of these voters • C. all people who have voted • D. the sample mean age of people who voted in the last election Answer Key: B Question 7 of 20 1.0/ 1.0 Points A Priest is interested in the proportion of couples who stay married after he marries them. Identify the sample: • A. all the couples the priest marriages • B. a subgroup of couples the priest marriages • C. the proportion of the sample of the priest's couples who stay married • D. the proportion of all couples who stay married Answer Key: B Question 8 of 20 1.0/ 1.0 Points An APU instructor is interested in the mean number of days an APU statistic students are absent from class during a quarter. The instructor’s sample produces a mean number of days absent of 5 days. This value is an example of a: • A. parameter • B. statistic • C. data • D. variable Answer Key: B Question 9 of 20 1.0/ 1.0 Points An APU instructor is interested in the mean number of days an APU statistic students are absent from class during a quarter. X = number of days an APU statistic students are absent from class during a quarter. In this case, X is an example of : • A. data • B. a statistic • C. population • D. a variable Answer Key: D Question 10 of 20 1.0/ 1.0 Points A local Polling chapter is interested in the proportion of people who voted in the last election. Identify the statistic. • A. the proportion of the sample who voted in the last election • B. all people (maybe in a certain geographic area, such as everyone in the state) • C. a group of the people • D. the proportion of all people who voted in the last election Answer Key: A Part 3 of 5 - Section: Frequency, Frequency Tables and Measurement 1.67/ 2.0 Points Question 11 of 20 1.0/ 1.0 Points Use the following information to answer the question: The (incomplete) table below contains data on hurricanes that have made direct hits on the U.S. Between 1851 and 2004. A hurricane is given a strength category rating based on the minimum wind speed generated by the storm. Frequency of Hurricane Direct Hits Category Number of Direct Hits Relative Frequency Cumulative Frequency 1 115 0.3758 0.3758 2 107 0.7255 3 65 4 15 0.0490 5 4 1.0000 Total=306 What is the relative frequency of direct hits that were category 3 hurricanes? • A. Not enough information to calculate • B. 0.2124 • C. 0.0490 • D. 0.0131 Answer Key: B Feedback: Good job! Question 12 of 20 0.67/ 1.0 Points Forbes magazine published data on the best small firms in 2012. These were firms which had been publicly traded for at least a year, have a stock price of at least $5 per share, and have reported annual revenue between $5 million and $1 billion. The table below shows the ages of the chief executive officers for the first 73 ranked firms. Age Frequency Relative Frequency Cumulative Relative Frequency 40-44 4 45-49 3 50-54 15 55-59 20 60-64 21 65-69 8 70-74 2 Answer the following questions: What percentage of CEOs are 59 years or younger? Round your answer to the nearest tenth. 57.5 % What is the relative frequency of ages 65 to 69? Round your answer to 4 decimal places .1096 What is the cumulative frequency for CEOs over 55 years in age? Round to a whole number. Do not include any decimals. 70 Answer Key: 57.5, 0.1096| .1096, 51 Feedback: % 20+21 + 8 + 2 = 51 Part 4 of 5 - Section: Variation and Rounding Off 5.0/ 5.0 Points Question 13 of 20 1.0/ 1.0 Points Click to see additional instructions Round the following number to four decimal places. Make sure you include a zero in front of the decimal. 0.7 0.0637 Answer Key: 0.0637 Question 14 of 20 1.0/ 1.0 Points You are collecting the same data and receive very different results from your participants. What should you do? • A. Nothing, it is perfectly fine to have different samples. • B. Ignore your results. • C. Average your scores with the participate mean. • D. Reevaluate your accuracy. Answer Key: D Question 15 of 20 1.0/ 1.0 Points Education and graduation rate statistics for 50 US states were collected from local high schools . One analysis of this data found a strong connection between education and income indicating that higher levels of education in a community correspond to lower income. Which of the potential problems with samples discussed below could explain this connection? • A. Self-funded or self-interest study • B. Non-response or refusal of subject to participate • C. Misleading use of data • D. Confounding Feedback: Confounding: There are many factors that define a community other than education level and crime rate. Communities with high crime rates and high education levels may have other lurking variables that distinguish them from communities with lower crime rates and lower education levels. Because we cannot isolate these variables of interest, we cannot draw valid conclusions about the connection between education and crime. Possible lurking variables include police expenditures, unemployment levels, region, average age, and size. Answer Key: D Question 16 of 20 1.0/ 1.0 Points A population is: • A. a number that is a property of the population. • B. the collection of all individuals, objects or measurements that can be made • C. a characteristic of interest for each person or thing in the population. • D. a portion of the population under study. Answer Key: B Question 17 of 20 1.0/ 1.0 Points At the premiere of a new movie in the US, a poll of the movie goers opinions were asked if they liked the movie or not. As they were walking out of the movie, they had the opportunity to take the survey and submit their results at a ballot box. A large sample size was represented, and this poll was repeated again one week later with similar results at the movie premiere in the UK. When working with this data, which of the following statements best applies? • A. The surveys are biased because people chose to respond or not. • B. Because of the large sample size, the results are most accurate of all members of the community. • C. The same sampling methods were used for both polls, demonstrating reliability. • D. This is a Simple Random Sample Answer Key: A Part 5 of 5 - Section: Measurement Scale Questions 1.0/ 3.0 Points Question 18 of 20 0.0/ 1.0 Points What measurement scale is used in the following example? Time of day: morning, afternoon, evening, night • A. Nominal • B. Ordinal • C. Ratio • D. Interval Answer Key: B Question 19 of 20 0.0/ 1.0 Points What measurement scale is used in the following example? Number of children a person has. • A. Nominal • B. Interval • C. Ratio • D. Ordinal Answer Key: C Question 20 of 20 1.0/ 1.0 Points What measurement scale is used in the following example? A satisfaction survey of a local restaurant: 1=Very Satisfied 2= Satisfied 3= Somewhat Satisfied 4=Not Satisfied • A. Interval • B. Ratio • C. Nominal • D. Ordinal Answer Key: D