Research Strategies: How Psychologists Ask and Answer Questions
The Scientific Method
Theory - an explanation using an integrates set of principles that organizes observations and
predicts behaviours or events
Hypotheses - a testable prediction, often implied by a theory
Operational Definitions - a statement of the procedures (operations) used to define research
variables. Ex. human intelligence may be operationally defined as "what an intelligence test
Replication - repeating the essence of a research study, usually with different participants in
different situations, to see whether the basic finding extends to other participants and
Our theory will be useful if it 1. organizes a range of self-reports and observations 2. implies
predictions that anyone can use to check the theory or to derive practical applications.
Eventually, we will end up with a revised theory.
We will observe and describe people often drawing conclusions about why they act as they
1. Case Studies
An observation technique in which one person is studied in depth in the hope of revealing
Stories can be misleading, numbers can be numbing, remember an anecdote is not evidence.
2. Naturalistic Observation
Observing and recording behaviour in naturally occurring situations without trying to
manipulate and control the situation. ex. Studying chimps in nature to unobtrusive videos of
parent-child interactions in other cultures.
Does not explain behaviour, it describes it.
3. The Survey
A technique for ascertaining the self-reported attitudes or behaviours of a particular group,
usually by questioning a representative, random sample of the group.
Wording Effects, Random Sampling (resist choosing a few vivid but unrepresentative cases). A
representative sample is the best choice.
Population - all of the cases in a group being studied, from which samples may be drawn. (Not including a country's population)
Random Sample - a sample that fairly represents a population because each member has an
equal chance of inclusion.
A measure of the extent of which two factors vary together, and thus of how well either factor
predicts the other.
Correlation Coefficient - a statistical index of the relationship between two things. Remember
this helps us see the world more clearly by revealing the extent to which two things relate.
Scatter Plot - a graphed cluster of dots, each of which represents the values of two variables.
The slope of points suggest the direction of the relationship between two variables. The
amount of scatter suggests the strength of the correlation.
Correlation and Causation
Ex. Self esteem correlates negatively with depression. But does low self-esteem cause
depression? No matter how strong the relationship is, association does not prove causation.
Correlation indicates the possibility of a cause-effect relationship.
Experiments - enable researchers to isolate the effects of one or more factors by 1)
manipulating the factors of interest & 2) holding constant other factors.
Experimental Group - the group that is exposed to the treatment, that is, to one version of the