A positive statement are statements that can be tested, changed, or rejected by checking it against facts.
Example: Higher interest rates will reduce house prices.
Normative Statements
A normative statement is a subjective statement of opinion which cannot be tested.
Example: The government should increase the minimum wage.
Unscrambling Cause and Effect
Ceteris paribus: other things being equal, or other things remaining the same.
In other words, we let one factor vary and hold the other relevant factors constant to investigate the effects of the factor in economic models. This will allow us to see the cause and effect.