Thinking Critically with Psychology

Theory An explanation that organizes facts to predict E.g. Self image and depression Black holes in space

Generally based on a theory Hypothesis A testable prediction Generally based on a theory

What do you study? - Variables Independent variable Dependent variable

How are variables related? - Correlation Positive and negative

Positive correlation Mortality rates increase as people age Grades increase as study time increase

No (zero) Correlation

Negative correlation As income increases free time decreases As one goes up, the other goes down

Illusory correlation Buying stocks that performed well last year Adoption and conception

Confusing correlation with causation “Correlation is not causation” Large brains (or ice cream) & violence

How do you get people to study? Population All NSCC students Representative Sample Random sample Ensures a representative sample Random assignment

Random sampling

Research methods Survey Case study Naturalistic Observation E.g. Stroke victim Naturalistic Observation Observing behavior in a singles bar Experimentation

The experiment Groups Problems Experimental group Control group Placebo effect Placebo = Pill with no drug The double blind procedure Neither experimenter nor subject knows which pill is the drug or placebo. Hawthorne effect Subjects give the results they think the experimenter wants

Comparing research methods

Replication Repeating a study Helps to confirm the results of an earlier study E.g. Classroom learning vs. distance learning Cold fusion

Problem Thinking Seeing order in random events Generalizing (Problems) E.g. 10 heads in a row of coin toss Generalizing (Problems) Generalizing from unrepresentative samples Generalizing from select cases Most remedial reading students in Mrs. Brown’s class are boys Therefore, boys have more trouble reading than girls Hindsight bias Explaining events in hindsight Lee Harvey Oswald & Pres. Kennedy