Introduction to statistics
Population
All of the 'things' we are interested in such
as people, households, trains
Population parameter
(Describes entire population) is the
measurement value (size) of the population
For example:

population of Venezuela

population of Australian households
N represents the population size
For example:
population of Australian households N=
8,286,084
Sample
A subset of the population
Must be representative of the population if
we want to infer (generalise) our finding to
the population of 'things' (population of
interest). The sample must be
random
as a
random sample allows for an unbiased
representation of the population to take
place.
Sample statistic
Describe the sample
Number of scores in the sample
For example:

Measurement value (size) of the
sample

Sample of 2500 Australian
households
The sample statistic can provide us with an
estimation of the population parameter
n represents sample size
For example:

Sample from the population of
Australian households n=10,000
Variable
An overarching label of the element/
feature we want to measure
Variables must always vary
For example:

Gender  male, female, nonbinary
etc.

Age  in years, age group
Descriptive statistics
Organises raw information into
'manageable' information
Numerical and/ or graphical form