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PSYC 200Week #8Thinking Like a Psychologist Part II1AgendaRoll callCollect Essay #2Discuss APA Mastery TestDiscuss Term PaperTheories, Falsifiability, and More Plan for next week / Announcements23 Characteristics of ScienceSystematic EmpiricismMaking 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.Systematic Empiricism: psychology is based on empiricism what is? However, just looking at things is not going to explain how peoples brains work, so we look at the world in a systematic way that will answer our specific psychological questions = systematic.

Replication and Peer Review: 3Examples teach us what?Get into groups and discuss your assigned example.Be sure to discuss:The details / history of the exampleWhat principle the example illustratesWhy its important to psychologistsExample List:Little Green MenBirth controlling toastersAmazing RandiGoldbergerClever Hans & Facilitated Communication4Theories & HypothesesTheoryAn 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?FalsifiabilityHypothesisSpecific predictions derived from theories (Stanovich, 2010, p. 21)Testable predictions.5The Falsifiability CriterionWhat is falsifiability?A property of a scientific theoryThe theorys ability to be incorrectA theory or prediction that cannot be wrong is not falsifiable and therefore, not scientific

Pick 5 volunteers6Operationalism and Essentialism 7Constructs, Concepts, and RealityConcept: an idea/phenomenon given a specific name and definitionoften 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.

8EssentialismThe 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 worksone CANNOT discover the essence of something through observation.9OperationalismThe act or practice of trying to define something by observation.Love isThe relative degree of pupil dilation when the significant other enters the persons field of viewAn increased level of oxytocin present in the persons pre-frontal cortexGravity 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 operationally10Operational Definition PracticeLets try making some operational definitions of these constructsAnxietyReading abilityGood driving skillsDepressionIntroversionHunger

11Reliability and ValidityReliability: consistency over time or situationsTest-retest reliabilityInter-rater reliabilityValidity: accuracy of measurement (are you really measuring what you claim to be measuring and onlythe 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.12Testimonials and Case StudiesHow to think straight about them13Case StudiesAn in-depth study of one particular subjectGives a detailed portrayal of one persons experienceThe studys purpose is to present reality as it happens (whether good or bad)Subject to peer review and public scrutiny from the scientific worldUseful for the early stages of investigation helps uncover variables, issues, etc.14TestimonialsAn individuals personal experience to show support for a product, treatment, or truth.A person gives a detailed portrayal of his/her experienceThe persons 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.15Whats wrong with testimonials?Theres a testimonial for almost EVERY treatment, therapy, product, or service. If everything works, nothing works.Testimonials describe what worked for ONE personnot 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 EffectThe Vividness Problem16Placebo EffectPeople get better without treatment/therapyThey think theyre getting treatment

In studies, it is necessary to compare results of treatment to placebo effect.(Without controlling for placebo effect, cant tell whether the thought of treatment or the actual treatment caused changes.)17Vividness ProblemA 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 accidentPlane flight vs. car rideTestimonials are often vivid, moving accounts of an individuals experiencesthese tend to be persuasive (but are worthless to prove a claim).18PsuedoscienceClaims of truth and reality that claim to be rooted in science, but are NOT.AstrologyGraphologyPsychic ReadingsBiorythmsPsychoanalysisMuch of the self-help literatureMisdirects, misinforms, misguidesIs NOT Psychology19Correlation and CausationA common misconception20Relationship vs. Cause2 things can be related WITHOUT one causing the otherShoe size and heightIce cream sales and crime ratesSAT scores and college performanceSynonyms for relatedX predicts YX correlates with YX varies with YIndividuals with high X have high Y (or low)

21Relationship vs. CauseIncorrect words when things are only relatedX causes YX leads to YX increases Y (misleading)

When reading or conducting relational research, must be careful in interpreting results. NO CAUSAL INFERENCE ALLOWED.

22Correlational ResearchStudies 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 finalToasters and pregnancyCell-phone use and cancer (maybe)

23Correlations ProblemsWhen 2 variables are correlated, one cannot establish a causal link w/o more research.Correlation doesnt prove causalityThe 3rd variable problemGoldberger eats S!-!|TDisease was correlated to poor sanitationDisease was correlated to poor nutritionPoor sanitation was correlated to poor nutritionThe Directionality ProblemOne cannot determine, from correlation, which causes which. (self-esteem and academic performance)

24ControlNecessary to make causal inferences and rule out alternative explanationsWhen a researcher holds everything in 2 (or more) different situations constant except for a particular variableRequires that we separate and individually control variables that may naturally occur togetherThen if the outcome changes, the only explanation is the variable that changedOutcome = Dependent VariableManipulated variable = Independent Variable25Control (contd)VariablesQuiet ConditionNoisy ConditionNoise Level (IV)LowHighIQ (EV)AverageAverageRoom Temperature (EV)7082Sex of Subjects (EV)60% Female60% FemaleTask Difficulty (EV)ModerateModerateTime of Day (EV)MorningAfternoon26Control (contd)The Control GroupA group of participants that receives no (or alternative) treatmentWhy important?Examples of importanceClever HansFacilitated CommunicationSeparation of VariablesMust rule out alternative explanations; therefore must create artificial situations where variables that naturally occur together are teased apart.27Intro to Research Methods28Research MethodsThere are 6 basic categories of scientific method that virtually all research falls intoResearchNon-ExperimentalExperimentalNaturalistic ObservationQuasi-ExperimentalSurveyRelational ResearchField StudyExperimental29Research Methods Naturalistic ObservationAddresses most basic scientific question: What is out there?Requires operational definition of events to be observedObserver must be unobtrusive, and design must be nonreactive

30Research Methods Field-Based ResearchLike naturalistic observation, conducted in real-world settingsGoal is to establish natural relations among eventsObserver must be unobtrusive, but methods are intentionally reactive

31Research Methods Survey ResearchAppropriate to the study of private behaviorsTwo primary styles:Interviews (structured/unstructured)Questionnaires (structured/unstructured)

32Research Methods Relational (Correlational) ResearchGoal to verify systematic (usually linear) relations among eventsStrengths/directions of relationsgenerally expressed in form of correlation coefficient (rxy)33Research Methods True ExperimentGoal: to establish a cause-effect relationship among eventsDoes 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?

34Research Methods True ExperimentRequires:random assignment of participants to at least two equivalent conditionsmanipulation 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)35Research Methods True ExperimentConcludes: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, thenmanipulation of the IV caused the difference in the DV

36Research Methods Quasi-ExperimentGoal also to establish cause-effect relations among eventsRequired when random assignment is not possible, becausemust use pre-existing groups, orIV impossible to manipulate directly, orIV unethical/illegal to manipulate directly

37Research Methods ReviewName 6 categories of scientific researchWhich method of research can be used to establish cause and effect relationships?38