Question

) The table below shows (lifetime) peptic ulcer rates (per 100 population), UU, for various family incomes, xx, as reported by the 1989 National Health Interview Survey.

Income	4000	6000	8000	12000	16000	20000	30000	45000	60000
Ulcer rate	13.6	13.6	12.9	12.6	12.6	12.3	11.1	9.2	8

(a) Find the equation of the regression line.

Ulcer rate, U(x)=U(x)= .

(b) Estimate the peptic ulcer rate for an income level of x0=x0= 23000 according to the linear model in part (a).

Ulcer rate, U(x0)=U(x0)= .

Answer 1

We can use here Excel for regression equation

Step 1) Enter data in Excel .

Step 2) Data >>Data analysis >>Regression >>Select y and x values separately >>Ok

a) U(x) = y=14.0371-0.0001x

b) Substitute x=23000 in above regression equation

=> U(23000)=14.0371-0.0001(23000)

=11.7