tailieunhanh - Ebook Methods in behavioral research (12th edition): Part 2

(BQ) Part 2 book "Methods in behavioral research" has contents: Experimental design, conducting experiments, complex experimental designs; single case, quasi experimental, and developmental research; understanding research results - description and correlation, generalization, understanding research results - statistical inference. | 9 Conducting Experiments LEARNING OBJECTIVES j j j j Distinguish between straightforward and staged manipulations of an independent variable. Describe the three types of dependent variables: self-report, behavioral, and physiological. Discuss sensitivity of a dependent variable, contrasting floor effects and ceiling effects. Describe ways to control participant expectations and experimenter expectations. j List the reasons for conducting pilot studies. j Describe the advantages of including a manipulation check in an experiment. 179 THE PREVIOUS CHAPTERS HAVE LAID THE FOUNDATION FOR PLANNING A RESEARCH INVESTIGATION. In this chapter, we will focus on some very practical aspects of conducting research. How do you select the research participants? What should you consider when deciding how to manipulate an independent variable? What should you worry about when you measure a variable? What do you do when the study is completed? SELECTING RESEARCH PARTICIPANTS The focus of your study may be children, college students, elderly adults, employees, rats, pigeons, or even cockroaches or flatworms; in all cases, the participants or subjects must somehow be selected. The method used to select participants can have a profound impact on external validity. Remember that external validity is defined as the extent to which results from a study can be generalized to other populations and settings. Most research projects involve sampling research participants from a population of interest. The population is composed of all of the individuals of interest to the researcher. Samples may be drawn from the population using probability sampling or nonprobability sampling techniques. When it is important to accurately describe the population, you must use probability sampling. This is why probability sampling is so crucial when conducting scientific polls. Much research, on the other hand, is more interested in .