Statistics Vocabulary SM1
Vocab. Word
Symbol
Definition
Measure of
center: mean,
median, mode
A measure that represents the center, or typical value of a
data set
mean
The sum of the data divided by the number of data values
median
The middle number when the numbers are written in
numerical order (if even #, then the mean of the 2 middle
values).
mode
The value or values that occur most often. (none, one, or
many possibilities)
Measure of
variation
A measure that describes the spread or distribution of the
data set
range
Greatest value - least value
Standard
deviation
The measure of how much a typical value differs from the
mean.
InterQuartile
Range
IQR
The difference between the third quartile Q3 and the first
quartile Q1. It is the range of the middle half of the data.
Example
residual
The difference between predicted values of y (dependent
variable) and observed values of y
Linear regression
Uses a straight line to estimate the relationship between
one independent variable and one dependent variable.
Lines of best fit
Uses linear regression to find a straight line that is the best
approximation of the given set of data
Correlation
coefficient
r
Shows how strong a relationship is between data. Values
are between -1 and 1,
1 strong positive, -1 strong negative, 0 no relationship
interpolation
Using a graph or equation to approximate a value that lies
between two known values (inter is between something we
know)
Extrapolation
Using a graph or equation to predict a value outside of
known values (extra using information that we don’t know)
causation
One event causes another to occur.
Causation produces a strong correlation between two
variables. The opposite is not true. Correlation does not
imply causation.