How To Do Psychology: Methods Pt. 1
P S YC H 1101 P ROF. DAVID P IZ AR RO DAY 2
www.cornellpsych.net
1103 sections
Science A method for arriving at knowledge about the natural world, with the goal of explaining why things are the way that they are.
Scientific Explanation "A satisfying explanation invokes principles that are fewer in number, more general, earlier in the causal chain, and closer to irreducible physical and mathematical laws than the ones that immediately fit the data in question." S TE VE N P INK E R
Richard Feynman On The Scientific Method (Cornell Lectures, 1964)
yo u c an s ee all of t he Feynman C orn e ll lec t u r e s her e: h t t p : / / r e s e a r c h . m i c r o s o f t . c o m / a p p s / t o o l s / t u v a /
Recipe For Science 1. Take your best guess about a general principle, explanation, law! 2. See what specific predictions arise from this general guess! 3. Compare this prediction to what you see in nature (experiment, experience, observation)! 4. Does it match your prediction? If not, reject theory (falsification rather than verification).! 5. Repeat, Share, Refine
Can Be Problematic In Practice • • • • • • •
Dumb guesses about underlying law/principle (“turtles all the way down”)! Vague, imprecise, or unfalsifiable theories ! Sloppy method of observation/measurement/experimentation! Data analysis done incorrectly! Unjustified conclusion from limited results! Stubborn scientists/Scientists motivated to find what they want! Fraud
‌But It Works Better Than Anything Else
How To Do Scientific Psychology? 1. Take your best guess about a general principle, explanation, law! 2. See what specific predictions come out of this guess! 3. Compare this prediction to nature (experiment, experience, observation)! 4. Does it match your prediction? If not, reject theory (falsification rather than verification).! 5. Repeat, Refine, Share
Get Data
How Do Psychologists Get Their Data? • •
There are likely just as many methods as there are topics ! Most methods can be grouped into one of three categories:!
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Unobtrusive Observation! Survey/Self-Report! Experimentation!
(In practice, these are often combined)
Varieties Of Observation •
A number of ways to collect data through observation. E.g., !
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Sit in playground and make note of which kids play in groups or alone ! Stand behind a 2-way mirror and watch subjects while they work on a puzzle ! Videotape people standing in line and make note of when they decide to switch!
Concerns that observation can change behavior have led researchers to develop less obtrusive measures
What Your Stuff Says About You: Observing “Behavioral Residue”
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Observation of dorm rooms, bedrooms, offices...even Facebook profile pages.!
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Reliably correlated with “Big 5” personality characteristics (especially extraversion).
Ethical Considerations
Middlemist, Knowles, & Matter (1977)
“Personal space invasions in the lavatory: suggestive evidence for ar ousal.�!
Self-Report •
Surveys, questionnaire measures, interviews!
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Often easy to collect, inexpensive, and quick!
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Problems!
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Social desirability! Dishonesty! Lack of insight/access to information being studied!
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e.g., how racist are you? how smart are you?
Correlation Is Not Causation
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Observational and self-report measures can yield good data, but cannot determine causality
Experimentation •
Gold standard of science, because it can determine causality!
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Control group vs. experimental group!
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Manipulate something (the independent variable)!
Random assignment (each person has an equal likelihood of being assigned to either group)!
Measure the outcome (the dependent variable)
Happy Labor Day! We’ll Continue With Methods On Wednesday.