Question

A dietetics student investigated the relationship between calcium intake and knowledge about calcium (a score out of 50) in sports science students. The relationship is: (Calcium intake) = 371.8 + 14.0 x (Knowledge score) with r = 0.80. The best interpretation of the intercept is:

Answer 1

Solution

Back-up concept

For the linear regression model Y = β₀ + β₁X + ε, in the estimated regression: Y_cap = β_0cap + β_1capX,

β_0cap represents the y-intercept mathematically and physically represents the expected value

of the response (dependent) variable when the predictor (independent) variable is zero ....................... (1),

β_1cap represents the slope of the regression line mathematically and physically represents

the expected change (increase/decrease) in value of the response (dependent) variable when

the predictor (independent) variable changes (increases/decreases) by one unit………...............….... .. (2)

Now the interpretation,

Going by (1), the interpretation would be: even when sports science students are ignorant about calcium (meaning a score of 0 for the x-variable), the expected calcium intake would be 371.8. Answer

[going beyond, vide (2), with every increase of calcium knowledge score by one point, the expected calcium intake would increase by 14]

DONE