Sometimes called quantitative variables. Called Scale data in SPSS.
Interval variables that can be measured along a continuum and they have a numerical value.
Ratio variables are interval variables, but with the added condition that 0 (zero) of the measurement indicates that there is none of that variable.
Sometimes called qualitative, discrete, or dichotomous variables. Called Ordinal and Nominal data in SPSS.
Ordinal data that has a distinct order. There’s a meaning to the order.
Nominal data are distinct groups with no meaning to the order.
IV 
DV 
TEST 

Continuous  Continuous 

Categorical (≥ 2 groups)  Categorical (≥ 2 groups) 

Categorical (2 groups)  Continuous 

Categorical (1 group 2 conditions)  Continuous 

Categorical (≥ 2 groups)  Continuous 

1 Group  Continuous (≥ 3 conditions) 

IV 1 
IV 2 
DV 
TEST 

Continuous  Continuous  Continuous 

Continuous (≥ 2)  Continuous 


Continuous (≥ 3) 


Continuous  Continuous or Categorical  Continuous 

Continuous  Continuous or Categorical  Continuous 

Continuous (≥ 1)  Categorical (≥ 1)  Categorical (2 groups) 

Continuous (≥ 1)  Categorical (≥ 1)  Categorical (≥ 3 groups) 

Categorical  Categorical  Categorical 

Categorical  Categorical  Continuous 

Categorical  Categorical  Continuous 

Categorical  Categorical or Continuous  Continuous 

Categorical (≥ 1)  Categorical (optional)  Continuous (≥ 2) 

Categorical (≥ 1)  Categorical (optional)  Continuous (≥ 2) 
