GENERAL PSYCHOLOGY
Chapter 2
Research Methods
Case Studies
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Used to provide an in-depth analysis of a person or small group
Typically performed on persons with exceptional life experiences or abilities (both positive and
negative)
Limitation: results cannot be generalized to other similar cases
A meta-analysis of many cases may provide a more useable result
Observation
Observation is used to study directly observable behavior.
Naturalistic Observation: Studying behavior in its natural environment.
Advantage: Behaviors are more real and unrehearsed.
Disadvantage: No control over outside variables.
Laboratory Observation: Studying behavior in a simulated environment.
Advantage: Gain control over outside variables.
Disadvantage: Subjects feel "on stage" and may perform behaviors not seen in a natural
environment.
Both types of observation may be either:
Unobtrusive: Subjects are not aware of being observed.
-- or -Obtrusive: Subjects are aware they are part of a study.
Non-participant: Researcher observes subjects from afar and has no interaction with the subjects.
-- or -Participant: Researcher actively interacts with subjects during the process of observing them.
Survey Methods
Survey research is used to assess attitudes, opinions, beliefs and perceptions that cannot be
assessed by direct observation. In some cases, surveys are also used as a self-report method to
assess the frequency of certain behaviors (ex: how many times a day do you brush your teeth?).
When survey research is designed, a population is first defined, then, a percentage of the
members of the population are chosen to participate. Subjects chosen from the population to be
subjects in survey research are referred to as a sample.
In order for a researcher to be able to generalize the results of a survey to the general population,
the survey sample must be representative of the population. The best and most effective method
of drawing a representative sample is to choose subjects on the basis of random selection. When
subjects are chosen for a survey sample on a purely random basis, factors such as age, sex, race,
SES, religion, political affiliation will mirror that of the population. Therefore, it is essential to select
survey participants randomly.
There are two forms of surveys that include:
Questionnaires: A document that the subject fills out on his/her own. Can have open-ended or
close-ended questions. Advantage: anonymous, efficient. Disadvantage: response rate
Interviews: Information is collected verbally, in an interactive exchange. Can be done face to
face, or over the telephone. Advantage: more detailed & personal, and guaranteed response rate.
Disadvantage: socially desirable responses, time/labor intensive
Correlational Research
Correlational research is used to examine the relationship between variables as they occur
naturally in society. No manipulation of variables is attempted.
Correlational studies are conducted when a formal experiment cannot be done because (1) the
variables being studied can't be controlled and manipulated in an experiment or (2) the variables
being studied cannot be ethically studied in an experiment. The results of correlational research
can only be used to determine if a relationship exists between variables. Because of potentially
unlimited uncontrolled variables, NO CAUSE AND EFFECT RELATIONSHIP CAN BE
DETERMINED.
A correlation coefficient is a number (determined from a complex statistical formula) that indicated
two aspects of the relationship between variables. First, it indicates the strength of the relationship
(how likely the variables are to occur together). Second, it indicates the type of relationship
whether it is a positive or a negative correlation). The number will fall somewhere between -1.0
and +1.0. The closer the number is to either the -1 or the +1, indicates a strong relationship
between variables. Numbers closer to zero indicate a weak relationship. Simply put, the larger
the number (regardless of whether it is a - or +), the stronger the relationship between variables.
Formal Experiments
Formal experiments are used to examine the relationship between two variables in a controlled
setting. Experiments are said to be the most powerful and accurate research method because
they involve controlling for the influence of outside variables. If an experiment is conducted with
excellent control measures and reveals statistically significant results, A CAUSE AND EFFECT
RELATIONSHIP CAN BE DETERMINED.
Formal experiments always involve at least two groups including an experimental group (which
receives the variable being tested) and a control group (which receives "the usual treatment").
The control group is used to provide a basis for comparison for changes which might occur in the
experimental group.
In an experiment, two variables are identified. The independent variable is the variable being
tested that is expected to cause a change in another variable. The dependent variable is the
variable that is expected to be changed or altered as a result of the independent variable.
In many experiments, the control group must be given a placebo (a fake) in order to control for
expectation effects. Example: If the experimental group is given caffeine in coffee, the control
group must be given the placebo of decaffeinated coffee. Otherwise, the mere expectation of
change resulting from drinking coffee might prove as significant an effect as the actual caffeine
itself.