1. Copyright © 2010 Allyn & Bacon This multimedia product and its contents are protected under copyright law. The following are prohibited by law: any public performance or display, including transmission of any image over a network; preparation of any derivative work, including the extraction, in whole or in part, of any image; any rental, lease, or lending of the program. PowerPoint Presentations for Psychology The Science of Behavior Seventh Edition Neil R. Carlson, Harold Miller, C. Donald Heth, John W. Donahoe, and G. Neil Martin Prepared by Linda Fayard Mississippi Gulf Coast Community College

2. Copyright © 2010 Allyn & Bacon Chapter 2 The Ways and Means of Psychology

3. Copyright © 2010 Allyn & Bacon The Ways and Means of Psychology 1. The Scientific Method in Psychology 2. Ethics 3. Understanding Research Results

4. Copyright © 2010 Allyn & Bacon The Scientific Method in Psychology Scientific Method:  Set of procedural research rules scientists should follow Three major types of research:  Naturalistic or clinical observation  Correlation study  Experiment

5. Copyright © 2010 Allyn & Bacon The Scientific Method in Psychology The five steps in an experiment:  Identifying the problem  Designing an experiment  Performing the experiment  Examining the data  Communicating the results

6. Copyright © 2010 Allyn & Bacon Identifying the Problem: Getting an Idea for Research What question do you want to study?  Go to the library and read what other people have found  Make your own observations  Talk to other researchers  Psyclit © or PsycINFO © are good places to start your search for new research ideas

7. Copyright © 2010 Allyn & Bacon Identifying the Problem: Getting an Idea for Research Research questions are translated into testable hypotheses  A hypothesis is a statement of what you think should happen in your experiment  A theory is a set of statements designed to explain a set of results and is more elaborate than a hypothesis

8. Copyright © 2010 Allyn & Bacon Identifying the Problem: Getting an Idea for Research Naturalistic observations  Observing animals in their natural environment  Remain in the background Clinical observations  In the form of case studies Survey studies  Asking people questions

9. Copyright © 2010 Allyn & Bacon Designing an Experiment  Independent variables  Dependent variables  Experimental group  Control group  Operational definitions  Confounding of Variables

10. Copyright © 2010 Allyn & Bacon Figure 2.1: Basic Design of the Driving and Cell Phone Distraction Experiment

11. Copyright © 2010 Allyn & Bacon Figure 2.2: Independent and Dependent Variables

12. Copyright © 2010 Allyn & Bacon Confounding of Variables  We must control our independent variable  Sometimes an unexpected variable is also introduced during an experiment; this is called a confound

13. Copyright © 2010 Allyn & Bacon Figure 2.5: A Schematic Representation of the Flawed Predator Experiment

14. Copyright © 2010 Allyn & Bacon Figure 2.6: Counterbalancing in the Predator Experiment  In the previous experiment, the order of the stimuli was always the same, and confounded the results  Counterbalancing the order of the stimuli prevents confounding

15. Copyright © 2010 Allyn & Bacon Performing an Experiment Reliability of Measurements  Are the measurements repeatable?  Subjectivity affects reliability  Inter-rater reliability

16. Copyright © 2010 Allyn & Bacon Performing an Experiment Selecting the participants  How do you select the participants?  Random assignment reduces confounding

17. Copyright © 2010 Allyn & Bacon Figure 2.7: A Possible Problem with the Anger and Concentration Experiment

18. Copyright © 2010 Allyn & Bacon Performing an Experiment Expectancy effects  Participant expectations  Single blind experiments  Experimenter expectations  Double blind experiments

19. Copyright © 2010 Allyn & Bacon Correlational vs. Experimental Studies  Correlational studies  cannot infer causation  can only state that there is a relationship between the variables of interest  may be due to a third unknown variable  Experimental studies  can infer a causal relationship between the variables of interest

20. Copyright © 2010 Allyn & Bacon Performing a Correlational Study

21. Copyright © 2010 Allyn & Bacon Reporting and Generalizing a Study  What does your experiment mean in the real world? (e.g. Haddock & Zanna, 1997) Generalization:  Can you apply your results to the population from which you took your sample?

22. Copyright © 2010 Allyn & Bacon Ethics  Research with Human Participants  Research with Animals

23. Copyright © 2010 Allyn & Bacon Research with Human Participants  Requires compliance with the following principles:  Minimize risk and maximize benefits  Informed consent  Deception generally unacceptable  Private lives generally off limits  Confidentiality  Vulnerable populations  Institutional Review Board (IRB)  Ensures compliance with ethics principles

24. Copyright © 2010 Allyn & Bacon Research with Animals  As animals cannot give informed consent, researchers must respond to the following questions:  Is the research important and worth doing?  Have we minimized harm to the animals?  Are the animals getting the best possible care?  Are the animals being treated humanely?

25. Copyright © 2010 Allyn & Bacon Understanding Research Results  Descriptive Statistics: What Are the Results?  Inferential Statistics: Distinguishing Chance from Significance

26. Copyright © 2010 Allyn & Bacon Descriptive Statistics: What are the Results? Descriptive statistics  Numeric descriptors  Central tendency (mean, median, and mode)  Dispersion (range, variance, and standard deviation)  Measurement of relations  Correlation coefficients range from 0 to 1  Can be positive or negative; indicates direction or relationship

27. Copyright © 2010 Allyn & Bacon Descriptive Statistics: What are the Results Graphing the data in a scatterplot  Linear relationships  Nonlinear relationships

28. Copyright © 2010 Allyn & Bacon Figure 2.9: A Scatterplot of the Test Scores and Average Grades of 10 Students

29. Copyright © 2010 Allyn & Bacon Figure 2.10: Scatterplots of Variables Having Several Different Levels of Correlation

30. Copyright © 2010 Allyn & Bacon Inferential Statistics: Distinguishing Chance from Significance  Calculates the probability that results are due to chance  Statistical significance is determined by statistical analyses performed on the data and found when an observed relation or difference between two variables is not due to chance

31. Copyright © 2010 Allyn & Bacon Figure 2.11: A Frequency Distribution