o Although much of what we learn from studying psychology is obvious, many
psychological results are surprising.
o Results that would seem surprising before we know what they are often seem
more obvious after we become aware of them.
Characteristics of Scientific Findings
In a scientific discipline,
(a) ideas are accurately reported and can be verified,
(b) researchers report findings publicly in scientific journals, and
(c) work is cumulative with respect to past research.
It is important to recognize some misconceptions about science. Science
(a) is not always correct,
(b) does not always follow the orderly progression of steps students learned as
“the scientific method”,
(c) is not always completely objective and value-free because it is practiced by
human beings, and
(d) is not merely a collection of facts.
How Scientist Solve Problems
Scientific problem solving is a though process. Typically it occurs in steps:
(a) identifying the problem,
(b) defining the problem,
(c) formulating hypothesis,
(d) constructing a strategy for solving a problem, and
(e) monitoring and evaluating problem solving
o The evaluation of the solution often leads to the recognition of a new challenge
and thus the repetition of the process.
o The steps of the process are not necessarily executed exactly in this order. Some
problems are refined as the process goes along or as new strategies are tired as old
The Goals of Scientific Research
When a problem is addressed, the goals of psychological research are:
Research Methods in Psychology
Psychologists employ research methods such as
b. Case studies
d. Questionnaires, and
o An experiment is a carefully supervised investigation in which a researcher
studies cause-effect relationships by manipulating one or more independent
variables in order to observe their effects on one or more dependent variables.
o An experiment should include at least one control group to ensure that differences
in results are caused by the experimental treatment and not by irrelevant group
o Because we generally cannot conduct studies on whole populations, we use
sample statistics (numbers that characterize the sample we have tested with
regards to the attributes under investigation) as estimates of the population
parameters (numbers that would characterize everyone we conceivably might test
who would fit our desired description).
o The use of sample statistics is based on the assumption that the researcher has
found a representative sample of the population under study.
o Although we are never able to prove the null hypothesis (which states that there is
no difference between two groups under study), we can demonstrate that a
particular difference has reached a level of statistical significance—that is, one
unlikely to have occurred if the null hypothesis (of no difference) were true.
Causal Inference in Psychological Research
o Psychological researchers try to draw causal inferences or conjectures about
o Controlled experimental designs are better suited to drawing such inferences than
are quasi-experimental designs, which lack at least one experimental
characteristic (usually random assignment of participants to groups), or
correlational designs, which shows associations between variables but not which
variables cause which others ones.
o Correlation is the degree of statistical relationship between two variables.
Correlation does not imply causation.
Critical Thinking in Psychological Research
o Critical thinking is of great importance to psychological research. When people
do not think critically, they are likely to commit informal fallacies, such as
irrelevant conclusions, composition, personalization, false cause, and ad hominem
o Scientists, including psychologists, must use ethical research procedures. Most
questions about ethics center on whether participants—human or animal—are
o Research institutions today have standard policies that require informed consent
by and debriefing of human participant.
o Most institutions have also set up institutional review boards to study and approve
proposed research. Some government agencies monitor research practices,
especially as they pertain to animals.