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148 PART II: Descriptive MethodsSTRETCHING EXERCISE IITwo student researchers have been asked to do asurvey to determine the attitudes of students towardfraternities and sororities on campus. Thereare 3,200 students in the school. About 25% ofthe students belong to the Greek organizationsand 75% do not. The two student researchersdisagree about what sampling plan is best for thestudy. One researcher thinks they should drawa stratified random sample of 200 students: 100from among those students who belong to Greekorganizations and 100 from among the independentstudents. The second researcher thinksthey should draw one simple random sample of100 students from the campus as a whole.1 Comment critically on these two sampling plans interms of their representativeness and the likelihoodthat they would measure reliably the views ofstudents who belong to Greek organizations.2 Develop your own sampling plan if you decide thatneither of the ones proposed so far is optimal.40 chemistry majors on campus, and you wish to describe the views of studentsaccording to different majors. Although this accurately reflects the proportionof chemistry majors in the campus population, it would be risky touse the views of only 2 chemistry students to represent all 40 chemistry majors(2 is too few). In this case (and more generally when a stratum is small in number),you could sample more chemistry majors to describe their views better.We can’t say precisely how many to sample because, as we learned earlier, thesample size needed to represent a population depends on the degree of variabilityin the population.SURVEY METHODS• Four methods for obtaining survey data are mail surveys, personalinterviews, telephone interviews, and Internet surveys.Selecting the sample is only one of several important decisions to makewhen doing survey research. You also need to decide how you will obtaininformation from the respondents. There are four general methods: mail surveys,personal interviews, telephone interviews, and Internet surveys. As isoften true when doing research, there is no one best survey method for all circumstances.Each survey method has its own advantages and disadvantages.The challenge you face is to select the method that best fits your researchquestion.Mail Surveys• Although mail surveys are quick and convenient, there may be a problemwith the response rate when individuals fail to complete and return thesurvey.• Due to problems with the response rate, the final sample for a mail surveymay not represent the population.Mail surveys are used to distribute self-administered questionnaires thatrespondents fill out on their own. One advantage of mail surveys is that they