statistics
a set of mathematical procedures for organizing, summarizing, and interpreting information
population
the set of all the individuals of interest in a particular study
sample
a set of individuals selected from the population, usually intended to represent the population in a research study
variable
a characteristic of condition that changes or has different values for different individuals
data
measurements or observations
data set
a collection of measurements or observations
raw score
a singular measurement or observation; aka datum
parameter
a value, usually a numerical value, that describes a population; usually derived from measurements of the individuals in the population
statistic
a value, usually a numerical value, that describes a sample; usually derived from measurements of the individuals in the sample
descriptive statistics
statistical procedures used to summarize, organize, and simplify data
inferential statistics
techniques that allow us to study samples and then make generalizations about the populations from which they were seleted
sampling error
the naturally occurring discrepancy, or error, that exists between a sample statistic and the corresponding population parameter
correlational method
two different variables are observed to determine whether there is a relationship between them
experimental method
one variable is manipulated while another variable is observed and measured. To establish a cause-and-effect relationship between the two variables, this method attempts to control all other variables to prevent them from influencing the results
independent variable
the variable that is manipulated by the researcher. In behavioral research, the ___ usually consists of the 2+ treatment conditions to which subjects are exposed. The ___ consists of the antecedent conditions that were manipulated prior to observing the d
dependent variable
the variable that is observed to assess the effect of the treatment
control condition
in the ____ individuals do not receive the experimental treatment. Instead, they either receive no treatment or they receive a neutral, placebo treatment. The purpose of a ____ is to provide a baseline for comparison with the experimental condition
experimental condition
in the ______ individuals do receive the experimental treatment
quasi-independent variable
the "independent variable" that is used to create the different groups of scores in a non-experimental study
constructs
internal attributes or characteristics that cannot be directly observed buy are useful for describing and explaining behavior
operational definition
identifies a measurement procedure (a set of operations) for measuring an external behavior and uses the resulting measurements as a definition and a measurement of a hypothetical construct. ____ has 2 components: (1) it describes a set of operations for
discrete variable
consists of separate, indivisible categories; no values can exist between two neighboring categories
continuous variable
there are an infinite number of possible values that fall between any two observed values. A _____ is divisible into an infinite number of fractional parts
real limits
the boundaries of intervals for scores that are represented on a continuous number line. The ____ separating two adjacent scores is located exactly halfway between the scores. Each score has two _____: the upper real limit (at the top of the interval) and
nominal scale
consists of a set of categories that have different names; measurements on a nominal scale label and categorize observations, but do not make any quantitative distinctions between observations
interval scale
consists of ordered categories that are all intervals of exactly the same size. Equal distances between numbers on a scale reflect equal differences in magnitude. However the zero point is arbitrary and does no indicate a zero amount of the variable being
ratio scale
an interval scale with the additional feature of an absolute zero point. With a _____, ratios of numbers do not reflect ratios of magnitude