AP Statistics 5.5: Interpreting LSRL Coefficients
Interpret an LSRL slope as predicted response change per explanatory-unit increase and judge whether the y-intercept has context.
- Syllabus
- Effective Fall 2025
- Course
- AP Statistics
Interpret an LSRL slope as predicted response change per explanatory-unit increase and judge whether the y-intercept has context.
A biologist gathered data on the length, in millimeters (mm), and the mass, in grams (g), for 11 bullfrogs. The data are shown in Plot 1.

From the data, the biologist calculated the least-squares regression line for predicting mass from length. The least-squares regression line is shown in Plot 2.

Official question visual
Identify and interpret the slope of the least-squares regression line in context.
The value of the slope of the least-squares regression line is 6.086. This value indicates that the predicted mass of a bullfrog increases by 6.086 grams for each additional millimeter of length.
Essentially correct (E) if the response satisfies the following three components:
2. Provides an interpretation that references an
increase of a number of grams of mass for each one-millimeter increase in length
3. Indicates that the slope represents a change in
a prediction using non-deterministic
language such as "predicted," "estimated,"
"expected," or "average"
Partially correct (P) if the response satisfies only two of the three components.
Incorrect (I) if the response does not meet the
criteria for E or P.
Additional Notes:
- The value of the slope, 6.086, may be rounded to 6.09 or 6.1, but not to 6, to satisfy the numerical requirement in component 1.
- A response that only contains 6.086 in the interpretation satisfies component 1.
- A calculation of slope may satisfy component 1, provided that two points from the line are used in the calculation.
- Units of measurements must be correctly specified for both mass and length to satisfy component 2.
- It is not required to refer specifically to the "least-squares regression line."
Model Solution
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