Question

In a regression equation predicting income (measured in $1000s) with education (measured in years), the intercept (a) equals 1.5 and the regression coefficient (b) equals 4. Which of the below is the correct interpretation of the intercept (a)?
a. at zero years of education, income equals $1500
b. when income equals zero, education equals 1.5

c. for every additional year of education, income increases $4000

d. for every four years of education, income increases $1000

Answer 1

Answer:

a. at zero years of education, income equals $1500

Step-by-step explanation:

The equation for income 'I', as a function of years of education 't' is given by:

$i(t) = bt+a$

Where b is the regression coefficient and a is the intercept.

The intercept is the value assumed by the function for t = 0 years of education:

$i(0) = 0*4 +1.5\\i(0) = 1.5$

Since the income function measures income in $1,000s, at zero years of education, income equals $1500