Question

两个变量满足下列关系:

X	10	15	20	25	30
Y	1 003	1 005	1 010	1 011	1 014

两变量回归直线方程为(    )

A.y=0.56x+997.4                        B.y=0.63x-231.2

C.y=50.2x+501.4                         D.y=60.4x+400.7

Answer 1

解析:=100,=5 043,=101 000,=2 250,=20,=1 008.6,

b===0.56,

a=-b=1 008.6-0.56×20=997.4.

答案:A