Variable
Random variable
True
Population
Hypothesis testing
Inferential statistics
Descriptive statistics
False
Discrete
False
Interval level of measurement
Nominal
Ratio
Nominal
True
Ordinal
Ratio
False
True
False
Continuous
B and C
A and B
A only
Both A and B
Both A and B
A only
C only
B only
False
False
Cluster
Stratified sampling
True
Voluntary response samples
Stratified sample
Cluster sample
Systematic sample
Simple random sample
Explanatory variable
True
True
Observational