What you’ll learn
Interpret slope/intercept in context.
Key idea
Slope has output units per input unit; intercept has output units only.
Slope is predicted dollars per item, intercept predicted dollars at zero; neither guarantees actual outcomes or causation.
Worked example
Classify examples and non-examples for the concept 'Interpret slope/intercept in context'.
Supplied fitted model y=1.50x+9 predicts cost y dollars from item count x in studied inputs 0..3. Classify the correct slope/intercept interpretation.
- The supplied fitted model y=1.50x+9 predicts $9 at zero items, included in the fitted input range.
- One additional item changes predicted output by $1.50; slope units dollars/item, intercept units dollars. These are predictions, not guaranteed measured costs or causal effects.
Answer: Predicted increase $1.50 per item, predicted zero-item cost $9 — coefficient and constant have their respective units.
Quick Check
Classify examples and non-examples for the concept 'Interpret slope/intercept in context'.
Supplied fitted model y=2.10x+12 predicts cost y dollars from item count x in studied inputs 0..3. Classify the correct slope/intercept interpretation.