66 ❯ STEP 4. Review the Knowledge You Need to Score High
might be tried. If two treatments are used, the order of the treatments could cause an effect.
To eliminate the possibility, psychologists use counterbalancing, a procedure that assigns
half the subjects to one of the treatments first and the other half of the subjects to the other
treatment first.Quasi-Experimental Research
Quasi-experimental research designs are similar to controlled experiments, but partic-
ipants are not randomly assigned. Experimental research designs to study differences in
behavior between men and women, boys and girls, young and old, or students in one
class and students in another class are “sort of” experiments or quasi-experiments. Because
of confounding variables—preexisting differences between the experimental group and
comparison groups—quasi-experiments do not establish cause and effect relationships,
although they can point in the direction of them.Correlational research
Although experiments conducted under carefully controlled conditions help establish cause
and effect relationships, the time, expense, and artificiality of the environment limit that
type of research. Psychologists more often use descriptive and correlational research meth-
ods such as survey methods that involve interviews or questionnaires, tests, and naturalistic
observation. Correlational methods look at the relationship between two variables without
establishing cause and effect relationships. The goal is to determine to what extent one
variable predicts the other. Many factors that seem to be causally related are not. Often it’s
a third factor that causes the other two.Naturalistic Observation
Naturalistic observation is carried out in the field where naturally occurring behavior can
be observed. Naturalistic observation studies gather descriptive information about typi-
cal behavior of people or animals without manipulating any variables. For example, Jane
Goodall’s team of scientists has been observing the behavior of chimpanzees in the wild for
decades. Such studies have enabled scientists to predict when the chimps will fight each
other or when they will mate. Similarly, other scientists have been studying human behav-
ior in the workplace, in schools, in bars, etc. The data can be used for correlational analysis
or for generating ideas for other research.Survey Method
In the survey method, researchers use questionnaires or interviews to ask a large number of
people questions about their behaviors, thoughts, and attitudes. In order for the informa-
tion to be useful, the participants in the study should be representative of a larger popula-
tion, which can best be achieved by random sampling. Accuracy of data is an issue because
people sometimes distort their answers to appear more “politically correct,” or they fail to
recall information correctly. The data from surveys can be used for correlational analysis or
for generating ideas for other research.
Retrospective or ex post facto studies look at an effect and seek the cause. For example,
when researchers found an increase in babies being born with deformed limbs, especially in
England but also in the United States and other western countries in the early 1970s, they
asked the mothers of the babies many questions and then compared the answers of all of
the mothers through correlational analysis. They found the strongest relationship between
the mother taking the drug thalidomide during the pregnancy and the appearance of the
limb deformities in the babies. Controlled experiments with rodents verified that the drug
caused abnormal limb development in the babies of the animals.