The Second Edition of An Applied Guide to Research Designs offers researchers in the social and behavioral sciences guidance for selecting the most appropriate research design to apply in their study. Using consistent terminology, the authors visually present a range of research designs used in quantitative, qualitative, and mixed methods to help readers conceptualize, construct, test, and problem solve in their investigation. The Second Edition features revamped and expanded coverage of research designs, new real-world examples and references, a new chapter on action research, and updated ancillaries.
The regression-discontinuity (RD) approach is often referred to as an RD design. RD approaches maintain the same design structure as any basic between-subjects pretest and posttest design. The major differences for the RD approach are (a) the method by which research participants are assigned to conditions and (b) the statistical analyses used to test the effects. Specifically, the researcher applies the RD approach as a means of assigning participants to conditions within the design structure by using a cutoff score (criterion) on a predetermined quantitative measure (usually the dependent variable, but not always). Theoretical and logistical considerations are used to determine the cutoff criterion. The cutoff criterion is considered an advantage over typical random or nonrandom assignment approaches as a means to ...