1. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 The Research Endeavor

2. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 The Scientific Method Conducting scientific research involves: Defining a problem Specifying a testable hypothesis Operationalizing the dependent and independent variables

3. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 Case Studies Detailed histories of individuals who have suffered some form of psychological disorder. Case studies have been used for centuries as a way of trying to understand the experiences of single individuals and to make more general inferences about the sources of psychopathology.

4. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 Correlational Studies Continuous Variable Two or more variables are measured and the correlation between them is examined Group Comparison Study Two or more groups are compared on the variables of interest Cross-sectional Participants assessed at one point in time Longitudinal Participants assessed on two or more occasions over times

5. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3

6. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 Evaluating Correlational Studies External validity- the extent to which the results can be generalized to real life Disadvantages- cause vs. consequence, timing, third variable problem Advantages- reflect real world problems

7. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 Epidemiological Studies Prevalence rates - the measure of a condition in a population at a given point in time Incidence rates - the number of new occurrences of a condition (or disease) in a population over a period of time Risk factors - traits and lifestyle habits that increase the risk of disease.

8. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 Research Methods in Psychology Because it can generate cause-and-effect statements, many psychologists believe that the experimental method is the most powerful research approach. By manipulating an independent variable (the cause), the researcher determines whether it influences the dependent variable (the effect).

9. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 Research Methods in Psychology By manipulating an independent variable (the cause), the researcher determines whether it influences the dependent variable (the effect).

10. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 Evaluating Human Laboratory Studies Advantages Researcher has more control over variables. Participants can be randomly assigned to groups. Appropriate control groups can be created to rule out alternative explanations of important findings. Disadvantages Results may not generalize to outside the laboratory. There are ethical limitations.

11. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 Evaluating Therapy Outcome Studies Advantages They provide help to people in distress as research is generated. Disadvantages It is difficult to tell which aspect of therapy led to reduction in the psychopathology. Raises questions about appropriate control groups. Ethical considerations. Patients’ needs must be balanced with the need to administer standardized therapy. Generalizability of results to real- world delivery of therapy is unclear.

12. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 Multiple Baseline

13. Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 3 Reversal Designs Subjects are observed over a series of periods in which the IV is and then is not manipulated Ex: effect of hostility by parents on social withdrawal in children Ex: effects of a drug on schizophrenic symptoms