CHAPTER 1

1. CHAPTER 1 Thinking Critically with Psychological Science

2. The Limits of Intuition and Common Sense • Hindsight Bias (I-knew-it-all along phenomenon): The tendency to believe, after learning an outcome, that one would have foreseen it.

4. The Limits of Intuition and Common Sense • Overconfidence: The tendency to think we know more than we do. We tend to be more confident than correct * It is because of hindsight bias and overconfidence that we need scientific inquiry

6. The Scientific Method • Steps in the Scientific Method • Define the Problem • Develop a Hypothesis • Test the Hypothesis • Analyze the Results • Draw a Conclusion

7. Scientific Method • Example: • Define the Problem: Students have many misconceptions about behavior

8. Scientific Method • Develop a Hypothesis: If students take a psychology course then they will have fewer misconceptions about behavior

9. Scientific Method 3. Test the Hypothesis: Have students take a pre-test concerning behavior. After taking a psychology course, have the same students take a post-test on human behavior.

10. Scientific Method 4. Analyze the Results: Compare the scores the students received on the pre-test as opposed to the post test. Note if there is a statistically significant overall improvement.

11. Scientific Method 5. Draw a Conclusion: If there is an overall improvement in the students’ scores it can be concluded that taking a psychology course does reduce the number of misconceptions that students have concerning behavior.

12. Scientific Method • Now you try it • Define the Problem • Develop a Hypothesis • Test the Hypothesis • Analyze Results • Draw a Conclusion

13. The Scientific Method • Theory: A tentative explanation that must be subjected to scientific evaluation based on critical thinking • Hypothesis: A specific testable proposition about a theory one wants to study

14. The Scientific Method • Operational Definition: A statement describing the exact operations or methods used to manipulate and/or measure the variables in research

15. Description • The Case Study Method: A case study is an in-depth investigation of an individual or a small group. Psychologists use what they learn from a case study to generalize broader principles that apply to the larger population

16. Description • The Case Study Method was the method of choice for: • Sigmund Freud • Jean Piaget • Neuropsychologists

17. Description • Advantages of the Case Study Method • Case studies provide detailed, descriptive analyses of new, complex, or rare phenomena

18. Description • Disadvantages of case studies • Some cases may be atypical and therefore generalizations to the larger population are not possible 2. Case studies are often based on interviews. People may not be able to remember important information or may have inaccurate recollections.

19. Description • Survey Method: • A research method that involves giving people questionnaires or special interviews designed to obtain descriptions of their attitudes, beliefs, opinions, and intentions. This provides a broad portrait of large groups`

20. Description • Have you ever participated in a survey?

21. Description • The Survey • Wording Effects: Subtle changes in the order or wording of questions can have big effects on the results • You need to avoid “loaded words” • You must be certain to make the questions clear

22. Description • The Survey • Population: A group of people with an important characteristic in common • Examples? • Target Population: The whole group that you want to study or describe and from whom samples may be drawn

23. Description • Random Sample: • A sample in which each and every member of the target population has an equal chance of being chosen. If your sample is random, you can assume that your sample is an accurate representation of your target population

24. Description • What are some examples of the consequences of having a sample that is NOT random?

25. Sample Size Activity Imagine that you are a golfer of above average ability (like me) and that you have the opportunity to play the greatest golfer in the world (for argument sakes let’s say Tiger Woods). If you want to maximize your slim chance of winning, how much golf should you elect to play, given the choices of 1, 18, 36, or 72 holes? Why?

26. Sample Size Activity A certain town is served by two hospitals. In the larger hospital about 45 babies are born each day, and in the smaller hospital about 15 babies are born each day. Although the overall proportion of boys is about 50% the actual proportion at either hospital may be greater or less than 50%on any day. At the end of a year, which hospital will have the greater number of days on which more than 60% of the babies born were boys? (a) the larger hospital (b) the smaller hospital (c) neither—the number of days will be about the same within 5 percent of each other

27. Sample Size Activity Imagine an urn filled with white and black balls. You know that two-thirds of the balls are one color and one-third are the other, but you don’t know which color predominates. One blindfolded person plunges a hand into the urn and comes up with 3 black balls and 1 white ball. Another uses both hands and comes up up with 14 black balls and 10 white balls. Which sample provides the more convincing evidence (to the thinking person) that the urn contains more black balls than white balls? (a) the first, or 3:1 sample (b) the second, or 14:10 sample (c) they are equally convincing

28. Description • False Consensus Effect: We overestimate others’ agreement with us • Representative Sample of the Population Onecan’t survey the total population so it’s important that the sample that is surveyed accurately represents the target population being studied. One way to ensure that the sample is a representative sample of the population is to have a random sample

29. Description • Advantages of the Survey Method • One can gather large amounts of descriptive data relatively quickly and inexpensively

30. Description • Disadvantages of the Survey Method • Sampling Errors • Poorly phrased questions • Response biases • One can not explain behavior, one can only describe behavior

31. Description • The Naturalistic-Observation Method: The study of behavior in naturally occurring situations without manipulation or control on the part of the observer.

32. Description • The Naturalistic Observation Method was the method of choice for Jane Goodall who studied chimpanzees in the African Jungle

33. Description • Advantages of the Naturalistic Observation Method: It is the best way of gathering descriptive data • Disadvantages of the Naturalistic Observation Method: It describes behavior but does not explain behavior

34. Correlation • A correlation is a statistical analysis of the degree to which two variables are related to each other and thus how well one predicts the other

35. Correlation • Sometimes it is not possible to conduct an experiment • Due to ethics • Due to pragmatics • Due to studying events that have already occurred In cases such as these, a researcher may conduct a correlation to see if two variables are somehow related.

36. Correlation does not imply causation!

37. Pick one and explain why one should not conclude a causal relationship. • The more TV is on in the homes of young children, the less time they spend reading. • The more sexual content teens see on TV, the more likely they are to have sex. • The longer children are breast-fed, the greater their later academic achievement. • The more income rose among a sample of poor families, the fewer psychiatric symptoms their children experienced.

38. Correlational Studies

39. Correlation Practice • Read the descriptions below and decide if there is a positive, negative, or no correlation Time spent exercising & weight ____ Study time & grades______ Car size & miles per gallon____ Stork population & human births_____ Distance from a sound & loudness______ Body size & intelligence_____ Years of schooling & salary_______

40. Correlation Practice Which correlation would allow the most accurate prediction of one variable from another? .00 +1.35 -.87 +1.00 Which correlation would allow the most accurate prediction of one variable from another? -.87 -1.20 +.85 -.30

41. Correlation Practice Let’s assume that students who are tardy to class often tend to have more detentions. If we were to correlate these two variable, the resulting correlation would be • A. near zero • B. between +1.00 and +2.00 • C. greater than 0 but less than +1.00 • D. less than 0, but greater than -1.00

42. Correlation • Illusory Correlation: the perception of a relationship where none exists Why does this happen? Examples?

43. Correlation • Perceiving Order in Random Events • Due to our inherent need to organize we tend to make order out of random events • Example: HHHTTT HTTHTH HHHHHH

44. The Experimental Method • This is the ONLYmethod of study that allows one to conclude a cause and effect relationship

45. The Experimental Method • Experiment: the researcher manipulates one variable (IV), observes the effect of that manipulation on a second variable (DV), while keeping all other variables constant.

47. The Experimental Method • Single Blind (Single Mask): An experimental procedure in which the participants are unaware of the experimental treatment, manipulation, or drug administered

48. The Experimental Method • Double Blind (Double Mask): An experimental procedure in which both the experimenters and the participants are unaware of the experimental treatment, manipulation, or drug administered

49. The Experimental Method A double blind helps prevent experimenter bias (which could be a confounding variable in an experiment)

50. The Experimental Method • Placebo Effect: A clinically significant response to a therapeutically inert substance or nonspecific treatment