PSYC 200 Week #8

1. PSYC 200Week #8 Thinking Like a Psychologist Part II

2. Agenda • Roll call • Collect Essay #2 • Discuss APA Mastery Test • Discuss Term Paper • Theories, Falsifiability, and More • Plan for next week / Announcements

3. 3 Characteristics of Science • Systematic Empiricism • Making observations about the world in such a way that reveals something about how the world works. • Replication and Peer Review (Public Knowledge) • All scientific knowledge is to be shared with public (other scientists) for them to review its credibility and to attempt replication. • Empirically Solvable Problems (Testable Theories) • Psychologists only work to solve problems / answer questions that are answerable by empirical methods.

4. Examples teach us what? • Get into groups and discuss your assigned example. • Be sure to discuss: • The details / history of the example • What principle the example illustrates • Why its important to psychologists • Example List: • Little Green Men • Birth controlling toasters • Amazing Randi • Goldberger • Clever Hans & Facilitated Communication

5. Theories & Hypotheses • Theory • “An interrelated set of concepts that is used to explain a body of data and to make predictions about the result of future experiments” (Stanovich, 2010, p. 21) • A systematic and falsifiable explanation for observable events that is based on observable events. • Theory vs. Guess? • Falsifiability • Hypothesis • “Specific predictions derived from theories” (Stanovich, 2010, p. 21) • Testable predictions.

6. The Falsifiability Criterion • What is falsifiability? • A property of a scientific theory • The theory’s ability to be incorrect • A theory or prediction that cannot be wrong is not falsifiable – and therefore, not scientific

7. Operationalism and Essentialism

8. Constructs, Concepts, and Reality • Concept: an idea/phenomenon given a specific name and definition—often lack strong empirical evidence for its “existence.” • Construct: an idea/phenomenon or collection of related ideas/phenomena that are given a specific name and definition. Often has strong empirical evidence for its “existence.” • All constructs must be operationalized to be of use to psychology.

9. Essentialism • The act or practice of trying to find the “essence” of something. • What does it really mean to love? • What is gravity, really? • Concerned with “ultimate” definitions or essential properties. • Not how science works—one CANNOT discover the “essence” of something through observation.

10. Operationalism • The act or practice of trying to define something by observation. • Love is… • The relative degree of pupil dilation when the significant other enters the person’s field of view • An increased level of oxytocin present in the person’s pre-frontal cortex • Gravity is the force that causes all objects with mass to move toward each other. • Concerned with observable definitions or empirical properties. Defining concepts using measurement. • HOW SCIENCE WORKS – we define our terms operationally

11. Operational Definition Practice • Let’s try making some operational definitions of these constructs • Anxiety • Reading ability • Good driving skills • Depression • Introversion • Hunger

12. Reliability and Validity • Reliability: consistency over time or situations • Test-retest reliability • Inter-rater reliability • Validity: accuracy of measurement (are you really measuring what you claim to be measuring and only—the whole truth and nothing but the truth) • Construct validity – do the measures/treatments match the construct? • Content validity – does the measure represent all the facets of the construct? • Best operational definitions are both reliable and valid.

13. Testimonials and Case Studies How to think straight about them…

14. Case Studies • An in-depth study of one particular subject • Gives a detailed portrayal of one person’s experience • The study’s purpose is to present reality as it happens (whether good or bad) • Subject to peer review and public scrutiny from the scientific world • Useful for the early stages of investigation – helps uncover variables, issues, etc.

15. Testimonials • An individual’s personal experience to show support for a product, treatment, or truth. • A person gives a detailed portrayal of his/her experience • The person’s purpose is to present reality as it happened (whether accurate or not) • NOT subject to peer review and are often solicited from providers of product/treatment.

16. What’s wrong with testimonials? • There’s a testimonial for almost EVERY treatment, therapy, product, or service. • If everything works, nothing works. • Testimonials describe what worked for ONE person—not what works for MOST people, or what WORKS BEST for most people. • “My Yugo lasted for 200K miles… it was the best car I ever had!” • Placebo Effect • The Vividness Problem

17. Placebo Effect • People get better without treatment/therapy • They “think” they’re getting treatment • In studies, it is necessary to compare results of treatment to placebo effect. • (Without controlling for placebo effect, can’t tell whether the thought of treatment or the actual treatment caused changes.)

18. Vividness Problem • A vivid example or case often carries more “weight” than a series of scientific studies. • Repeat criminals – an especially terrible crime by a repeat offender that gets lots of media attention will likely lead to new, tougher laws on 1st-time offenders (even if repeat offense rate is very low) • Abduction vs. car accident • Plane flight vs. car ride • Testimonials are often vivid, moving accounts of an individual’s experiences—these tend to be persuasive (but are worthless to prove a claim).

19. Psuedoscience • Claims of truth and reality that claim to be rooted in science, but are NOT. • Astrology • Graphology • Psychic Readings • Biorythms • Psychoanalysis • Much of the self-help literature • Misdirects, misinforms, misguides • Is NOT Psychology

20. Correlation and Causation A common misconception

21. Relationship vs. Cause • 2 things can be related WITHOUT one causing the other • Shoe size and height • Ice cream sales and crime rates • SAT scores and college performance • Synonyms for “related” • X predicts Y • X correlates with Y • X varies with Y • Individuals with high X have high Y (or low)

22. Relationship vs. Cause • Incorrect words when things are only related • X causes Y • X leads to Y • X increases Y (misleading) • When reading or conducting relational research, must be careful in interpreting results. NO CAUSAL INFERENCE ALLOWED.

23. Correlational Research • Studies whether 2 or more variables are “related” to each other. • When one increases, does the other increase? • When one increases, does the other decrease? • When one increases, does the other stay flat? • Things that are correlated: • Job Satisfaction and Pay? • Hours spent studying and score on final • Toasters and pregnancy • Cell-phone use and cancer (maybe)

24. Correlation’s Problems • When 2 variables are correlated, one cannot establish a causal link w/o more research. • Correlation doesn’t prove causality • The 3rd variable problem • Goldberger eats S!-!|T • Disease was correlated to poor sanitation • Disease was correlated to poor nutrition • Poor sanitation was correlated to poor nutrition • The Directionality Problem • One cannot determine, from correlation, which causes which. (self-esteem and academic performance)

25. Necessary to make causal inferences and rule out alternative explanations When a researcher holds everything in 2 (or more) different situations constant except for a particular variable Requires that we separate and individually control variables that may naturally occur together Then if the outcome changes, the only explanation is the variable that changed… Outcome = Dependent Variable Manipulated variable = Independent Variable Control

26. Control (cont’d)

27. Control (cont’d) • The Control Group • A group of participants that receives no (or alternative) treatment • Why important? • Examples of importance • Clever Hans • Facilitated Communication • Separation of Variables • Must rule out alternative explanations; therefore must create artificial situations where variables that naturally occur together are teased apart.

28. Intro to Research Methods

29. Naturalistic Observation Quasi-Experimental Survey Relational Research Field Study Experimental Research Methods • There are 6 basic categories of scientific method that virtually all research falls into Research Non-Experimental Experimental

30. Research Methods –Naturalistic Observation • Addresses most basic scientific question: “What is out there?” • Requires operational definition of events to be observed • Observer must be unobtrusive, and design must be nonreactive

31. Research Methods –Field-Based Research • Like naturalistic observation, conducted in real-world settings • Goal is to establish natural relations among events • Observer must be unobtrusive, but methods are intentionally reactive

32. Research Methods –Survey Research • Appropriate to the study of private behaviors • Two primary styles: • Interviews (structured/unstructured) • Questionnaires (structured/unstructured)

33. Research Methods –Relational (Correlational) Research • Goal to verify systematic (usually linear) relations among events • Strengths/directions of relations • generally expressed in form of correlation coefficient (rxy)

34. Research Methods –True Experiment • Goal: to establish a cause-effect relationship among events • Does low-fat diet cause decrease in cancer risk? • Does exposure to violent video games cause increase in violent behaviors? • Does spaced study cause increase in memory accuracy and retention? • Do genetic variations cause sexual preference?

35. Research Methods –True Experiment • Requires: • random assignment of participants to at least two equivalent conditions • manipulation of one factor (independent variable, or IV) in one condition (experimental), leaving it unchanged in other condition (control) • measurement of one other factor in both conditions (factor called dependent variable, or DV; measurement instrument called dependent measure, or DM)

36. Research Methods –True Experiment • Concludes: • if groups are NOT equivalent with respect to DV, and • if the difference between the groups is so big it probably did not happen by chance, then • manipulation of the IV caused the difference in the DV

37. Research Methods –Quasi-Experiment • Goal also to establish cause-effect relations among events • Required when random assignment is not possible, because • must use pre-existing groups, or • IV impossible to manipulate directly, or • IV unethical/illegal to manipulate directly

38. Research Methods Review • Name 6 categories of scientific research • Which method of research can be used to establish cause and effect relationships?