SPSS Vocabulary

variable

an empirical measurement of characteristics

nominal level variable

communicates differences between units of analysis on the characteristics measured

ordinal level variable

communicates relative differences between units of analysis

interval level variable

communicates exact differences between units of analysis

discrete values

count the number of times something occurs

continuous values

have an infinite number of unique values and can be estimated

central tendency

the variables typical on averga value

mode

the most basic measure of central tendency

median

the value of a variable that divides the case down the middle

mean

the arithmetic average

dispersion

the variation of cases across its values

frequency distribution

a tabular summary of variable values

raw frequency

reports the count of individuals at each of the variables values

proportion

the raw frequency divided by total frequency

percentage

the proportion multiplied by 100

cumulative percentage

records the percentage of cases at or below any given value of the variable

percentile

the percentage of cases in a distribution that lies below

bimodel distribution

a frequency distribution having two different values that are heavily populated with cases

Histogram

the percentage of cases falling into invervals of the variable

density plot

displays a running average of observations across the range of observed values

range

the maximum actual value minus the minimum actual value

interquartile range

the range of a variables values that defines the middle half of a distribution

standard deviation

the extent to which the cases in an interval-level distribution fall on or close to the mean of the distribution

skewness

a measure of symmetry

kurtosis

the shape of distribution, specifically how much it deviates from a bell-curve

Per-capita statistics

divide the total value of the thing be measured by the population size

unit of measurement

quantify and express the magnitude or size of different attributes or quantites

mean centering

subtracting the mean value of the variable from each observed value

standardizing

how many standard deviations higher or lower the score was

dummy variable

a variable that takes on only two distinct values to represent the presence or absence of a certain characteristic of category

Metadata

the information that describes the dataset

additive index

a summation of ordinal variables coded identically and all measure the same concept

Likert Scale

an additive index which captures the strength and direction of agreement

centrality

importance of nodes within a network

dependent variable

the variable that represents the effect in a casual explanation

independent variable

the variable that represents a casual factor in an explanation

theory