Statistics Vocabulary Chapters 1-5

Front 1

variable

Back 1

a property of people or objects that takes on two or more values

Front 2

statistics

Back 2

set of procedures used by social scientists to organize, summarize and communicate information

Front 3

data

Back 3

information represented by numbers, which can be the subject of statistical analysis

Front 4

3 steps of research process

Back 4

ask research question and formulate hypothesis
evaluate hypothesis
collect and analyze data

Front 5

empirical research

Back 5

research based on evidence that can be verified by using our direct experience

Front 6

theory

Back 6

elaborate explanation of the relationship between two or more observable attributes of individuals or groups

Front 7

hypothesis

Back 7

tentative answer to a research problem

Front 8

unit of analysis

Back 8

level of social life on which social scientists focus.
ex. individuals and groups

Front 9

dependent variable

Back 9

variable to be explained
"effect"

Front 10

independent variable

Back 10

variable expected to account for
"cause" of dependent variable

Front 11

nominal

Back 11

numbers or other symbols are assigned to a set of categories for the purpose of naming, labeling, or classifying the observations

Front 12

ordinal

Back 12

numbers are assigned to rank-ordered categories ranging from low to high

Front 13

interval-ratio

Back 13

measurements for all cases are expressed in the same units

Front 14

dichotomous variable

Back 14

variable that has only 2 values

Front 15

population

Back 15

total set of individuals, objects, groups, or events in which the researcher is interested

Front 16

sample

Back 16

relatively small subset selected from a population

Front 17

descriptive statistics

Back 17

procedures that help organize and describe data collected from either a sample or population

Front 18

inferential statistics

Back 18

logic and procedures concerned with making predictions or inferences about a population from observations and analyses of sample

Front 19

discrete variable

Back 19

minimum-sized unit of measurement
cannot be subdivided

Front 20

continuous variables

Back 20

range of values can be subdivided into increasingly smaller fractional values
ex. length

Front 21

frequency distribution

Back 21

table reporting the number of observations falling into each category of the variable

Front 22

proportion

Back 22

relative frequency obtained by dividing the frequency in each category by the total number of cases

Front 23

percentage

Back 23

relative frequency obtained by dividing the frequency in each category by the total number of cases and multiplying by 100

Front 24

percentage distribution

Back 24

table showing percentage of observations falling into each category of the variable

Front 25

cumulative frequency distribution

Back 25

distribution showing frequency at or below each category (class interval or score) of the variable

Front 26

cumulative percentage distribution

Back 26

distribution showing the percentage at or below each category (class interval or score) of the variable

Front 27

rate

Back 27

number obtained by dividing the number of actual occurrences in a given time period by the number of possible occurrences

Front 28

pie chart

Back 28

graph showing differences in frequencies or percentages among the categories of a nominal or ordinal variable.

Front 29

bar graph

Back 29

nominal or ordinal
rectangles of equal width with height proportional to frequency or percentage of category

Front 30

histogram

Back 30

interval-ratio level
contiguous bars

Front 31

frequency polygon

Back 31

interval-ratio
points representing the frequencies of each category are placed above midpoint of category and joined by straight line.

Front 32

time series chart

Back 32

displays changes in variable at different points in time
time on horizontal
frequencies on vertical

Front 33

measures of central tendency

Back 33

numbers that describe what is average or typical of the distribution

Front 34

mode

Back 34

category or score with highest frequency

Front 35

median

Back 35

score that divides distribution into 2 equal parts so that half the cases are above and half below

Front 36

percentile

Back 36

score below which specific percentage of the distribution falls

Front 37

mean

Back 37

obtained by adding up all the scores and dividing the total by the number of scores

Front 38

N

Back 38

number of observations

Front 39

skewed distribution

Back 39

distribution with a few extreme values

Front 40

negatively skewed

Back 40

few extremely low values

Front 41

positively skewed

Back 41

few extremely high values

Front 42

measures of variability

Back 42

numbers that describe DIVERSITY in the distribution

Front 43

index of qualitative variation
IQV

Back 43

nominal
based on ratio of total number of differences in distribution to maximum number of possible differences

Front 44

range

Back 44

interval-ratio
difference between highest and lowest scores

Front 45

interquartile range
IQR

Back 45

width of middle 50% of distribution
difference between lower and upper quartiles
Q3-Q1

Front 46

box plot

Back 46

low value
high value
Q1
Q3
median

Front 47

variance

Back 47

interval-ratio
average of squared deviations from the mean

Front 48

standard deviation

Back 48

interval-ratio
square root of variance