Ch#6 Choosing Research Subjects PDF

CH#6: CHOOSING RESEARCH SUBJECTS MSCM 541 - SUPPLY CHAIN CAPSTONE PROJECT POPULATIONS AND SAMPLES Population. May be defined in many ways. All children enrolled in day-care centers. Children in day care on a particular city. Sample. Small subgroup of subjects chosen from the population. Researchers...

CH#6: CHOOSING RESEARCH SUBJECTS MSCM 541 - SUPPLY CHAIN CAPSTONE PROJECT POPULATIONS AND SAMPLES Population. May be defined in many ways. All children enrolled in day-care centers. Children in day care on a particular city. Sample. Small subgroup of subjects chosen from the population. Researchers may need to define a subpopulation for study. RELATIONSHIP BETWEEN POPULATION AND SAMPLE Population All the items or individuals about which you want to draw conclusion(s). A Population of Size 40 Sample A portion of the population of items or individuals. A Sample of Size 4 COLLECTING DATA VIA SAMPLING IS USED WHEN DOING SO IS 1. Less time consuming than selecting every item in the population. 2. Less costly than selecting every item in the population. 3. Easier and more practical than analyzing the entire population. SOURCES OF DATA ARISE FROM THE FOLLOWING ACTIVITIES 1. Capturing data generated by ongoing business activities. 2. Distributing data compiled by an organization or individual. 3. Compiling the responses from a survey. 4. Conducting a designed experiment and recording the outcomes. 5. Conducting an observational study and recording the results. EXAMPLES OF DATA COLLECTED FROM ONGOING BUSINESS ACTIVITIES A bank studies years of financial transactions to help them identify patterns of fraud. Economists utilize data on searches done via Google to help forecast future economic conditions. Marketing companies use tracking data to evaluate the effectiveness of a web site. EXAMPLES OF DATA DISTRIBUTED BY AN ORGANIZATION OR INDIVIDUAL Financial data on a company provided by investment services. Industry or market data from market research firms and trade associations. Stock prices, weather conditions, and sports statistics in daily newspapers. EXAMPLES OF SURVEY DATA A survey asking people which laundry detergent has the best stain-removing abilities. Political polls of registered voters during political campaigns. People being surveyed to determine their satisfaction with a recent product or service experience. EXAMPLES OF DATA FROM A DESIGNED EXPERIMENT Consumer testing of different versions of a product to help determine which product should be pursued further. Material testing to determine which supplier’s material should be used in a product. Market testing on alternative product promotions to determine which promotion to use more broadly. EXAMPLES OF DATA COLLECTED FROM OBSERVATIONAL STUDIES Market researchers utilizing focus groups to elicit unstructured responses to openended questions. Measuring the time it takes for customers to be served in a fast food establishment. Measuring the volume of traffic through an intersection to determine if some form of advertising at the intersection is justified. OBSERVATIONAL STUDIES & DESIGNED EXPERIMENTS HAVE A COMMON OBJECTIVE In an observational study, there is no direct control over which items receive the treatment. In a designed experiment, there is direct control over which items receive the treatment. SOURCES OF DATA  Primary Sources: The data collector is the one using the data for analysis:  Data from a political survey.  Data collected from an experiment.  Observed data.  Secondary Sources: The person performing data analysis is not the data collector:  Analyzing census data.  Examining data from print journals or data published on the internet SAMPLING AND GENERALIZATION Goal of research studies: To apply results obtained from a sample to the larger population. Generalization is the ability to apply findings from a sample to the larger population. Random sample: A sample in which every member of the population has an equal chance of being chosen. Nonrandom sample: A sample in which every member of the population does not have an equal chance of being chosen (for example, chosen on the basis of convenience). NONRANDOM SAMPLING AND INTERNET RESEARCH Studies conducted on the Internet use a nonrandom sample. Why? because Participants are volunteers. Participants know how to use computers and have access to them. NONRANDOM SAMPLING AND INTERNET RESEARCH Two ways to demonstrate the validity of web-based research: 1. Compare the results from studies conducted on the Internet with the results of parallel studies conducted using traditional methods. 2. Evaluate the results from Internet-based research to check if they conform to theoretical predictions. NONRANDOM SAMPLING AND ANIMAL SUBJECTS Animals obtained from a single supplier do not constitute a random sample. Minor differences in a strain of rats may yield different results. For example: differences in drug effects. Findings cannot be generalized due to differences in strains used. Findings should be repeated using different strains of animals. IS RANDOM SAMPLING ALWAYS NECESSARY? Random sampling is most crucial when you want to apply results directly to a population. For example: predicting behavior from a survey or poll. Factors other than the sample that affect the generality of results: 1. How independent variables are manipulated. 2. Realism of the research setting. ACQUIRING HUMAN PARTICIPANTS Factors to consider when acquiring human participants for research. Field research. If the researcher is conducting a survey, one of several sampling techniques will be used. In a field experiment, the researcher can either wait for participants to happen along or recruit participants and randomly assign them to conditions. VOLUNTARY PARTICIPATION Ethical guidelines require that participation be voluntary. Using volunteer participants may affect internal and external validity of research. Volunteer bias: Sample made up of volunteers is a biased sample. Participant-related characteristics relate to volunteering. Compared to nonvolunteers volunteers usually are more highly educated, of a higher social class, are more social, and have a higher need for approval. Men and women differ, depending on the nature of the study. VOLUNTARY PARTICIPATION Situational factors affect the decision to volunteer in a complex way. People are less likely to volunteer for experiments that involve stress or aversive situations. Personal characteristics and incentives offered interact to affect the decision to volunteer. Media coverage may relate to willingness to volunteer. REMEDIES FOR VOLUNTEERISM Make the appeal as interesting as possible. Make the appeal as nonthreatening as possible. Explicitly state the theoretical and practical importance of the research for which volunteering is requested. Explicitly state why the target population is relevant to your research. Offer a small reward to participation. Avoid research tasks that may be physically or psychologically stressful. Have someone known to participants make the appeal for participants. DECEPTION IN RESEARCH Full disclosure may not be possible or desirable. Deception: Actively misleading participants or withholding information from participants. Two forms of deception: 1. Indirect deception: Not disclosing the full purposes or goals of a study. 2. Direct deception: Deliberately providing misinformation to participants about critical aspects of a study. DECEPTION IN RESEARCH Two main reasons for using deception: 1. To create interesting situations that are not likely to occur naturally. 2. When behavior can only be studied if a person is caught off guard. Proponents (supporters) of using deception argue that fully informing people produces behavior different from when they are caught unaware. RESEARCH DECEPTION IN CONTEXT Deception raises a number of methodological and ethical issues. Conduct a cost–benefit analysis. If benefits outweigh costs, deception is justified. Pure cost–benefit analysis may not be adequate. May require a social contract approach: Researcher and participant reach an agreement on how research should be conducted. If deception is used, participant should agree that as long as human dignity is maintained, some deception might be necessary. PROBLEMS INVOLVED IN USING DECEPTION Deceived participants react differently from nondeceived participants. Deceived participants are less likely to volunteer for future research. Deceived participants may feel duped and experience a loss of self-esteem or develop a negative attitude toward research. Participants may find out something negative about themselves. Deception may violate requirements of informed consent. SOLUTIONS TO THE PROBLEM OF DECEPTION Obtaining prior consent to be deceived. Participants told that some experiments may involve deception. Only those who agree to be deceived are chosen. Prior authorization to be deceived is obtained from the participant in informed consent form. THE END