Chapter 2 Research Methods

1. Chapter 2Research Methods It is actually way more exciting than it sounds!!!!

2. Conducting Research • 6 step process • Form a research question • Form a hypothesis • Test the hypothesis • Analyze results • Draw conclusions • Replicate study

3. Experimental Method • Formulate Hypothesis • Design Research/Study Method (type of method: naturalistic observation, case studies, surveys, experiments, etc.) • Collect the Data • Analyze the Data • Report the Findings (journal, critique, replicate) • Draw Conclusion or Theory on Explanation of Findings

4. Research terms to know • Hypothesis • testable prediction • Replication • Repeating the study to ensure outcome is the same

5. Types of research methods • Survey method • Case Study method • Naturalistic method • Correlational method • Longitudinal method • Cross-sectional method • Experimental method (laboratory or field)

6. The Survey Method • A technique for getting self-reported attitudes, opinions or behaviors of people usually done by questioning • Conduct via interview, mail, phone, or internet • They are cheap, anonymous, you get a diverse population, and easy to get a random sampling (sample that represents your population you want to study).

7. Sampling • Identify the population you want to study. • The sample must be representative of the population you want to study. • GET A RANDOM SAMPLE.

8. Survey Random Sampling If each member of a population has an equal chance of inclusion into a sample, it is called a random sample (unbiased). If the survey sample is biased, its results are not valid.

9. Survey Method - problems • Low Response Rate • People Lie or just misinterpret themselves. • Wording Effects • Wording can change the results of a survey

10. Case Studies • A detailed picture of one or a few subjects. • Tells us a great story…but it just describes behavior • Does not explain why anything is happening . The ideal case study is John and Kate. Really interesting, but what does it tell us about families in general?

11. Case Study Clinical Study A clinical study is a form of case study in which the therapist investigates the problems associated with a client. http://behavioralhealth.typepad.com

12. Naturalistic Observation • Watch subjects in their natural environment. • Do not manipulate the environment.

13. Correlational Research • Detects relationships between variables. • Does NOT say that one variable causes another. There is a positive correlation between ice cream and murder rates. Does that mean that ice cream causes murder?

14. Types of Correlation Positive Correlation • The variables go in the SAME direction. Negative Correlation • The variables go in opposite directions. Studying and grades has a positive correlation. Drug use and grades has a negative correlation

15. Correlation Positive Correlation As one number increases, the other increases. Ex: Study time to GPA Negative Correlation As one number increases, the other decreases. Ex: Absences to GPA

16. CORRELATION IS NOT CAUSATION!!! • People that floss everyday live 3 years longer than those that do not. • Red wine drinkers live longer than those that do not drink red wine. • As speed limits increased on America’s highways, the death rate went down. • Women with breast implants commit suicide 3 times as often as those without breast implants. • Children who are played Mozart in the womb have higher IQ’s. • Marijuana users in youth are more likely to have mental illness as adults. • As ice cream sales increased, so did shark attacks. • More TV’s per person in a country, the longer people live.

17. Experimental Method • Looking to prove cause and effect relationships. • Laboratory v. Field Experiments Smoking causes health issues.

18. Population & Sample • Identify the population you want to study. • The sample must be representative of the population you want to study. • GET A RANDOM SAMPLE.

19. Variables • Independent Variable (I.V.): manipulated by experimenter • Dependent Variable (D.V.): MEASURED variable influenced by independent • Operational definition • Confounding/extraneous variables

20. Random Assignment • Once you have a random sample, randomly assigning them into two groups helps control for confounding variables.

21. Assign participants to groups • Experimental group • Receives the independent variable • Control Group • Does not receive the independent variable • May receive a placebo • A false treatment • Make cause the placebo effect

22. Flaws in Research • Sampling Bias • Overgeneralization • Placebo effect • Hawthorne/Barnum effect • Experimenter Bias

23. Eliminating Experimenter bias Single-blind study Double-blind study Participants and experimenters are unaware who receives treatment • Participants do not know what group they are in

24. APA Ethical Guidelines for Research • IRB- Institutional Review Board • Must approve your study 1st • Both for humans and animals.

25. Human Research • No Coercion- must be voluntary • Informed consent • Confidentiality & Anonymity • Do not harm • Must debrief after

26. Animal Research • Clear purpose • Treated in a humane way • Acquire animals legally • Least amount of suffering possible.

27. Normal Distribution

28. Bell or Normal Curve 68% are within One standard deviation from mean 95% are within Two standard deviations from mean

29. Statistics Descriptive Statistics Central Tendency: mean – average median – middle score mode – most reoccurring number or numbers Measures of Variability: Standard deviation: shows how spread out the scores are from the mean Range: distance from smallest score to the largest score

30. Measures of Central Tendency A Skewed Distribution

31. Skews

32. Other measures of variability • Range: distance from highest to lowest scores. • Standard Deviation: the variance of scores around the mean. • The higher the variance or SD, the more spread out the distribution is. • Do scientists want a big or small SD? Shaq and Kobe may both score 30 ppg (same mean). But their SDs are very different.

33. Standard Deviation