Scientific Foundations of Psychology

Psychology

the scientific study of behavior and mental processes

Gestalt

looks at the human mind and behavior as a whole; suggests that we do not simply focus on every small component

Psychoanalytic Approach

how behavior springs from unconscious drives and conflicts

humanistic approach

How we meet our needs for love and acceptance and achieve self-fulfillment

Evolutionary Approach

how the natural selection of traits promoted the survival of genes

Biological Approach

how the body and brain enable emotions, memories, and sensory experiences

Cognitive Approach

how we encode, process, store, and retrieve information

Sociocultural Approach

how behavior and thinking vary across situations and cultures

biopsychosocial approaches

integrated approach; addresses biological, psychological, and social influences of a disorder

industrial-organizational domain

a subfield of psychology that applies psychological theories, principles, and research findings in workplace settings

experiment

A research method in which an investigator manipulates one or more factors to observe the effect on some behavior or mental process

correlational study

a research project designed to discover the degree to which two variables are related to each other

survey research

the most popular technique for gathering primary data, in which a researcher interacts with people to obtain facts, opinions, and attitudes

naturalistic observation

observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation

case studies

a research method that involves the intensive examination of unusual people or organizations

longitudinal studies

observational research method in which data is gathered for the same subjects repeatedly over a period of time

cross-sectional studies

observational research method where measures are taken at one moment in time instead of over a period

hypothesis

A testable prediction, often implied by a theory

operational definition

a statement of the procedures used to define research variables

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 circumstances

population

all the cases in a group being studied, from which samples may be drawn

random sample

a sample that fairly represents a population because each member has an equal chance of inclusion

control group

In an experiment, the group that is not exposed to the treatment; contrasts with the experimental group and serves as a comparison for evaluating the effect of the treatment.

experimental group

In an experiment, the group that is exposed to one version of the independent variable.

random assignment

assigning participants to experimental and control conditions by chance, thus minimizing preexisting differences between those assigned to the different groups

independent variable

The experimental factor that is manipulated; the variable whose effect is being studied.

dependent variable

The outcome factor; the variable that may change in response to manipulations of the independent variable.

double-blind procedure

an experimental procedure in which both the research participants and the research staff are ignorant (blind) about whether the research participants have received the treatment or a placebo. Commonly used in drug-evaluation studies.

placebo effect

experimental results caused by expectations alone; any effect on behavior caused by the administration of an inert substance or condition, which the recipient assumes is an active agent.

correlation

A measure of the extent to which two factors vary together, and thus of how well either factor predicts the other.

Scatterplot

a graphed cluster of dots, each of which represents the values of two variables

illusory correlation

the perception of a relationship where none exists

Validity

the extent to which a test measures or predicts what it is supposed to

confounding variable

an unknown third factor that is playing a role in the problem

measures of central tendency

statistical methods that characterize the typical value in a set of data

mean

the arithmetic average of a distribution, obtained by adding the scores and then dividing by the number of scores

median

the middle score in a distribution of scores; half the scores are above it, half the scores are below it

mode

the most frequently occurring score(s) in a distribution

measures of variance

refers to how much the numbers in the set differ from each other

range

the difference between the highest and lowest scores in a distribution

standard deviation

a computed measure of how much scores vary around the mean score

correlational coefficient

a number between -1 and +1 expressing the degree of relationship between two variables

frequency distribution

a mathematical function showing the number of instances in which a variable takes each of its possible values.

normal distribution

arrangement of a data set in which most values cluster in the middle of the range and the rest tape off symmetrically toward another extreme

bimodal distribution

an arrangement of a data set in which there are two "peaks" of data; indicates two groups of major trends

positive skew

more exceptionally large values than exceptionally small values

negative skew

more exceptionally small values than exceptionally large values

ethics

correct rules of conduct necessary when carrying out research; must respect rights and dignity of participants

informed consent

an ethical principle that research participants be told enough to enable them to choose whether they wish to participate

deception

the ethical principle that states no false information can be given to participants in an experiment of study; information can be withheld

right to withdraw

the ethical principle that states participants in a study or experiment have the right to remove themselves from the study at any time

protection from harm

ethical principle that insists participants in a study or experiment be protected from undue physical or psychological pain

confidentiality

the assurance that messages and information are available only to those who are authorized to view them

privacy

ethical principle that indicates researchers must be careful not to invade the privacy of participants

Institutional Review Board (IRB)

committee of administrators, scientists, and community members that reviews proposals for research involving human participants

Institutional Animal Care and Use Committee (IACUC)

a committee to review every experiment involving animals for ethics and methodology

statistical significance

a statistical statement of how likely it is that an obtained result occurred by chance

effect size

a measure of the strength of the relationship between two variables or the extent of an experimental effect

meta-analysis

a "study of studies" that combines the findings of multiple studies to arrive at a conclusion

percentile rank

the percentage of scores below a specific score in a distribution of scores

experimenter bias

a phenomenon that occurs when a researcher's expectations or preferences about the outcome of a study influence the results obtained

falsifiable hypothesis

a statement or prediction that can be tested and potentially proven false through experimentation or observation

directionality problem

a problem encountered in correlational studies; the researchers find a relationship between two variables, but they cannot determine which variable may have caused changes in the other variable

third-variable problem

the concept that a correlation between two variables may stem from both being influenced by some third variable

self-report bias

systematic errors that can occur in self-report data because participants are unable or unwilling to answer accurately

social desirability bias

the tendency to respond to questions in a socially desirable manner

convenience sampling

using a sample of people who are readily available to participate

sampling bias

A problem that occurs when a sample is not representative of the population from which it is drawn.

peer review

A process by which the procedures and results of an experiment are evaluated by other scientists who are in the same field or who are conducting similar research.