temperature measured with either the Fahrenheit or Celsius scale an interval

Temperature measured with either the fahrenheit or

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temperature, measured with either the Fahrenheit or Celsius scale (an interval-level variable), does not have a true zero. As was mentioned earlier, a major reason for categorizing data by level and type is that the methods you can use to analyze the data are partially dependent on the level and type of data you have available. E X A M P L E 1 - 1 Categorizing Data F or many years U.S. News and World Report has published annual rankings based on various data collected from more than 1,300 U.S. colleges and universities. Figure 1.13 shows a portion of the data in the file named Colleges . Each column corresponds to a different factor for which data were collected. Before doing any statistical analyses with these data, U.S. News and World Report employees need to determine the type and level for each of the factors. Limiting the effort to only those factors that are shown in Figure 1.13, this is done using the following steps: Step 1 Identify each factor in the data set. The factors (later to be called variables) in the data set shown in Figure 1.13 are College State Public (1) Math Verbal ACT # appli. # appli. # new % new % new # FT # PT in- Name Private (2) SAT SAT rec’d. accepted. stud. stud. stud. under- under- state enrolled from from grad grad tuition top 10% top 25% Each of the 14 columns represents a different factor. As shown in Figure 1.13, data are missing for some colleges and universities. Step 2 Determine whether the data are time-series or cross-sectional. Because each row represents a different college or university and the data are for the same year, the data are cross-sectional. Time-series data are measured over time—say, over a period of years. Step 3 Determine which factors are quantitative data and which are qualitative data. Qualitative data are codes or numerical values that represent cate- gories. Quantitative data are those that are purely numerical. In this case, the data for the following factors are qualitative: College Name State Code for Public or Private College or University
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CHAPTER 1 THE WHERE, WHY, AND HOW OF DATA COLLECTION 25 1-4: ExercisesSkill Development1-49.What is the difference between qualitative andquantitative data?1-50.For each of the following variables, indicate thelevel of data measurement:a.marital status {single, married, divorced, other}b.home ownership {own, rent, other}c.college grade point averaged.product rating {1 excellent, 2 good, 3 fair, 4 poor, 5 very poor}1-51.For each of the following, indicate whether the dataare cross-sectional or time-series:a.monthly salesb.unemployment rates by statec.quarterly unemployment ratesd.employment satisfaction data for a company1-52.What is the difference between ordinal andnominal data?1-53.Consumer Reports, in its rating of cars, indicatesrepair history with circles. The circles are eitherwhite, black, or half-and-half. To which level ofdata does this correspond? Discuss.Business Applications1-54.The manufacturer of a top-selling brand of laserprinters has a support center where customers cancall to get questions answered about their printer.
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