Psych Unit 2 - Approaches & Research in Psychology

Hindsight Bias

the tendency to believe, after learning an outcome, that one would have foreseen it

( Also known as the I-knew-it-all-along phenomenon )

Theory

an explanation using an integrated set of principles that organizes observations and predicts behaviors or events

Hypothesis

a testable prediction, often implied by a theory

Operational Definiton

a carefully worded statement of the exact procedures (operations) used in a research study

Example : human intelligence may be operationally defined as what an intelligence test measures

Replication

repeating the essence of a research study, usually with different situations, to see whether the basic finding can be reproduced

Case study

a descriptive technique in which one individual or group is studied in depth in the hope of revealing universal principles

Naturalistic Obersevation

a descriptive technique of observing and recording behavior in naturally occurring situations without trying to manipulate or control the situation

Survey

a descriptive technique for obtaining the self - reported attitudes or behaviors of a particular group, usually by questioning a representative, random sample of the group

Sampling Bias

a flawed sampling process that produces an unrepresentative sample

Population

all those in a group being studied, form which samples may be drawn

Random Sample

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

Correlation

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

Correlation Coefficient

a statistical index of the relationship between two things ( from -1.00 to +1.00 )

Variable

anything that can vary and is feasible and ethical to measure

Scatterplot

a graph cluster of dots, each of which represents the values of two variables. The slop of points suggests the direction of the relationship between the two variables. The amount of scatter suggests the strength of the correlation ( little scatter indicates high correlation )

Illusory Correlation

perceiving a relationship where none exists, or perceiving a stronger - than - actual relationship

Regression toward the mean

the tendency for extreme or unusual scores or events to fall back ( regress ) toward the average

Experiment

a research method in which an investigator manipulates one or more factors

( independent variables ) to observe the effect on some behavior or mental process

( the dependent variable )

Experimental Group

in an experiment, the group exposed to the treatment, that is, to no one version of the independent variable

Control Group

in an experiment, the group not exposed to the treatment ; contrast with the experimental group and serves as a comparison for evaluating the effect of the treatment

Random Assignment

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

Double - Blind Procedures

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 placebo

Placebo

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

Independent Variable

in an experiment, the factor that is manipulated ; the variable whose effect is being studied

Confounding Variable

a factor other than the factor being studied that might influence a study’s results

Dependent Variable

in an experiment, the outcome that is measured ; the variable that may change when the independent variable is manipulated

Validity

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

Informed Consent

giving potential participants enough information about a study to enable them to choose whether they wish to participate

Debriefing

the post experimental explanation of a study, including its purpose and any deceptions to its participants