PSYCHOLOGICAL RESEARCH METHODS AND STATISTICS

What is research?  Samples- relatively small group out of a whole population under study  Must be representative of the population in question  Random sample- each individual has an equal chance of being represented  Stratified sample- deliberately pick individuals who represent the various subgroups

Methods of Research  Naturalistic Observation  Observe behavior in natural environment  Avoid disturbing and stay inconspicuous  Case Studies  Most are long-term observations with diaries, tests, and interviews  Very powerful research tool, but cannot prove or disprove  Surveys  Most practical way to gather data on attitudes, beliefs, and experiences of large numbers of people  Can include questionnaires, interviews

Methods of Research  Longitudinal Studies  Studies same group of people at regular interviews over a period of years  Cross-Sectional Studies  Randomly selected groups organized on basis of age  Less expensive and time consuming than longitudinal studies  Correlations and Explanation  Want to examine relationship between two sets of observations and how they relate  Does not mean cause and effect

Experiments  Enables investigator to control the situation and decrease possible influences  Has hypothesis, variables, experimental group, control group  Can determine if independent variable influences behavior and how it does so  Final results do not constitute the final word on the subject  Experiment must be replicated

Ethical Issues  Ethics- methods of conduct, or standards, for proper and responsible behavior  Psychologists are responsible for dignity and welfare of participants  Must obey all state and federal laws and professional standards  Rights must be agreed on for researchers and participants before starting

Ethical Issues  When obtaining consent, everyone must be fully informed  Deception is used only if no better alternative is available, must not interfere with willingness to participate  The welfare and confidentiality of all participants are to be protected

Problems and Solutions in Research  Self-fulfilling prophecy- having expectations about a behavior and then acting in some way to carry out that behavior  Single-blind or double-blind techniques used to avoid  Single-blind experiment- participants are “blind” about treatment given  Double-blind- both researchers and participants are “blind” about the treatment given

The Milgram Experiment  1960s Stanley Milgram  Would participants administer painful shocks to others because an authority figure’s instruction?  2,000 paid male volunteers  “Learners” recited a memorized list  Every mistake required volunteer to deliver an electronic shock  Each shock would increase in voltage

The Milgram Experiment  “Learners” pretended to be shocked, volunteers thought it was real  Although it seemed hard, 62% of volunteers delivered a full range of shock up to maximum voltage  Later, volunteers were told that no actual shocking took place  Was this single-blind or double-blind?  Was this ethical?

The Placebo Effect  Placebo effect- a change in a participant's illness or behavior that results from a belief that the treatment will have an effect, rather than the actual treatment  1961 study-Experimental groups given “new drug”, control group given no drugs at all  After 6 weeks, 53-80% of experimental group noticed benefits  No group was given actual drugs during study