Interpreting Coefficients for Quantitative IVs

Consider the example from a dig site showing the relationship between dinosaur's femur length and body mass. 

For a one cm increase in femur length, we expect body mass to increase by 49 KG, holding all else constant (p < .05)

The expected weight for a dinosaur whose femur is 0 cm long is 255 kgs. 

Interpreting coefficients for Quantitative IVs

The coefficient of a quantitative independent variable in a regression model represents the change in the dependent variable that is expected given a one-unit change in the independent variable, while holding all other variables constant.

Take note of this formulaic explanation: For a one-unit increase in X, we can expect Y to increase/decrease by BETA units, holding all else constant (p<.05). 

The y-intercept can be interpreted as the expected value of Y when X is 0.