2 What qualifies research as science? Psychological research must meet certain criteria in order to be considered scientific.Research must be:1. Replicable2. Falsifiable3. Precise4. Parsimonious
3 ReplicableResearch is replicable when others can repeat it and get the same results.Q: If something is only true once, should we trust it?
4 FalsifiableA good theory or hypothesis also must be falsifiable, which means that it must be stated in a way that makes it possible to reject it. In other words, we have to be able to prove a theory or hypothesis wrong.
5 FalsifiableExample:Some people theorize that the Loch Ness Monster not only exists but has become intelligent enough to elude detection by hiding in undiscovered, undetectable, underwater caves. This theory is not falsifiable. Researchers can never find these undiscovered caves or the monster that supposedly hides in them, and they have no way to prove this theory wrong.
6 PreciseTo make hypotheses more precise, psychologists use operational definitions to define the variables they study. Operational definitions state exactly how a variable will be measured.Ex.:A psychologist conducts an experiment to find out whether toddlers are happier in warm weather or cool weather. She needs to have an operational definition of happiness so that she can measure precisely how happy the toddlers are. She might operationally define happiness as “the number of smiles per hour.
7 ParsimoniousThe principle of parsimony maintains that researchers should apply the simplest explanation possible to any set of observations.Example:Suppose a student consistently falls asleep in her statistics class. She theorizes that before each class, her statistics professor secretly sprays her seat with a nerve gas that makes her very drowsy. If she had applied the principle of parsimony, she would not have come up with this theory. She can account for her sleepiness with a much simpler and more likely explanation: she finds statistics boring.
8 The ExperimentAn experiment involves a set of controlled conditions that aim to confirm a hypothesis.Hypothesis refers to a statement of cause and effect:“Higher environmental temperatures lead to more aggression.”
9 Experimental Variables To test a hypothesis, an experimenter defines the variables of the hypothesis:Cause: Independent variable (IV)temperature: can be manipulated with intentEffect: Dependent variable (DV)aggression: # of acts of verbal/aggression in an hourThe experimenter “manipulates” the IV and measures the DV to test the hypothesis.
10 Experimental Issues Controls are important for determining causality the only difference between the experimental and control groups is the presence or absence of the IV.Placebo effects represent changes in behavior that are related to expectations of a treatment.placebo effects are controlled by a “blind” control groupExperimenter bias refers to expectations that influence a participant’s behavior.example: Clever Hans, the horse who could do mathcan be controlled using double blind procedures
11 Non-Experimental Research Naturalistic observation refers to systematic recording of behavior in a natural state or habitat.e.g. observing apes in the wildSurveys are instruments designed to sample attitudes or behaviors.e.g., asking students at a rally how they feel about animal rights issuesA case study is an in-depth study of a single person.e.g., Freud used the case study method to study anxietyCorrelations refer to looking at the relationship between two variables without manipulating them.
12 Correlation Techniques The correlation technique assesses the degree of association between 2 variables.Correlations vary in direction:Positive association: increases in the value of variable 1 are associated with increases in variable 2 (e.g., smoking and risk of cancer)Negative association: increases in variable 1 are associated with decreases in the variable 2 (e.g., years of education and risk of Alzheimer’s disease)No relation: values of variable 1 are not related to variable 2 (e.g., years of education and height)Correlations also vary in strength of the relationship-1 to 1
14 Correlation Take Home Line: Correlation does NOT imply causation!
15 What are the Goals of Psychology as a Science? Attempts to:1. Describe behaviorHow is he acting?2. Explain behaviorWhy is he acting this way?3. Predict behaviorWill this child be a serial killer?4. Control behaviorCan I keep others/myself from killing?Uses scientific method, not common sense.
16 Science vs. Common Sense Objective data collectionSubjective data collectionSystematic observationHit or miss observationReliance on evidenceIgnores counterevidence
17 Stanley Milgram’s Obedience Study 1963 social psychology experiment, subjects thought they were shocking another person to promote “learning”Many subjects delivered high level shocks and were upset when they later learned the true nature of the experimentThis study, and other factors, led to much more stringent APA research guidelines
18 Ethical Issues in Research Respecting the rights of human research participants involves:Informed consent is an explanation of a study and the responsibilities of experimenter and participant.Confidentiality of study information must be maintained.Debriefing refers to explaining the research process to the participants at the end of the study.Deception involving participants must be justified.Animal research must be justified and must minimize discomfort and pain.
19 Modern Psychology Views Psychoanalytic view emphasizes the unconscious mindBehaviorism focuses on objective and measurable behaviorsHumanistic psychology emphasizes the inner-self and the importance of subjective feelingsCognitive psychology focuses on mental function and reasoning
20 Modern Psychology Views Psychobiology views behavior as reflecting brain processesEvolutionary psychology asserts that certain behavioral characteristics are subject to natural selectionCultural psychology examines the influence of culture and ethnic practice on people’s behavior
21 Take Home Concepts Hypothesis What type of study? experimental, correlational, naturalisticobservation, case studyIndependent variable(s) (IV)Dependent variable(s) (DV)Control groupWere participants randomly sampledand assigned?Ethical concernsPotential experimenter and participant bias