hindsight bias
the tendency to believe, after learning an outcome, that one would have foreseen it (AKA i-knew-it-all-along phenomenon)
critical thinking
thinking that examines assumptions, discerns hidden values, evaluates evidence, and assesses conclusions
theory
an explanation using an integrated set of principles that organizes observations and predicts behaviors or events
hypothesis
a testable predictions, 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 to see whether the basic finding extends to other participants and circumstances
case study
an observation technique in which one person is studied in depth in the hope of revealing universal principles
survey
a technique for ascertaining the self-reported attitudes or behaviors of a particular group
population
all the cases in a group being studied
random sample
a sample that fairly represents a population because each member has an equal chance of inclusion
naturalistic observation
observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation
correlation
a measure of the extent to which two factors very together
correlation coefficient
a statistical index of the relationship between two things (from -1 to +1)
scatterplots
a graphed cluster of dots, each of which represents the values of two variables
illusory correlation
the perception of a relationship where none exists
experiment
a research method in which an investigator manipulates one or more factors to observe the effect of some behavior or mental process
random assignment
assigning participants to experimental and control groups by chance, thus minimizing the pre-existing differences between those assigned to the different groups
double-blind procedure
an experimental procedure in which both the research participants and the research staff are ignorant about whether the research participants have received the treatment or a placebo
placebo effect
experimental results caused by expectations alone
experimental group
the group that is exposed to the treatment
control group
the group that is not exposed to the treatment
independent variable
the experimental factor that is manipulated
dependent variable
the variable that may change in response to the manipulation of the independent variable
mode
the most frequently occurring score(s) in a distribution
mean
the arithmetic average of a distribution
median
the middle score in a distribution
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
normal curve
a symmetrical, bell-shaped curve that describes the distribution of many types of data
statistical significance
a statistical statement of how likely it is that an obtained result occurred by chance
culture
the enduring behaviors, ideas, attitudes, and traditions shared by a group of people and transmitted from one generation to the next