What you’ll learn
Interpret fitted-line slope and intercept.
Key idea
The constant is the zero-input prediction; the variable coefficient gives output change per input unit.
Separate zero-input prediction from per-hour change and never treat predictions as causal guarantees.
Worked example
Classify examples and non-examples for the concept 'Interpret fitted-line slope and intercept'.
Fitted quiz model y=4x+25, x=practice hours,y=predicted points. Classify this claim: intercept 4 points and rate 25 points/hour.
- At practice hours x=0, y=4x+25 predicts 25 quiz points.
- Every one-hour increment changes predicted points by 4; these model quantities do not prove practice causes the change.
Answer: False — intercept 25 predicted points at zero hours; slope 4 predicted points per additional hour.
Quick Check
Classify examples and non-examples for the concept 'Interpret fitted-line slope and intercept'.
Fitted quiz model y=7x+45, x=practice hours,y=predicted points. Classify this claim: intercept 45 points and rate 7 points/hour.