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A set of readings clearly bends into a curve rather than following a straight line. What use is a straight-line correlation figure here?
AIt shows how tightly the curve is bending
BIt gives the rate of change of the curve
CIt shows where the curve crosses the axis
DIt carries no useful meaning for this data
Answer & Solution
Correct answer: D. It carries no useful meaning for this data
1. A correlation figure for a straight-line fit measures how closely the readings follow a straight line.
2. These readings do not follow a straight line at all, they bend into a curve.
3. So the figure is measuring closeness to something the data was never going to match.
4. That makes the number meaningless for this set of readings.
5. Option A treats the figure as a measure of bending, which it never was.
6. Options B and C ask the figure to do the job of a rate of change or an intercept, which it also never was.
_Source: OpenStax College Algebra (CC BY 4.0), Ch 4 "Linear Functions", section 4.3 Fitting Linear Models to Data_
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