Question

An auto manufacturing company wanted to investigate how the price of one of its car models depreciates with age. The research department at the company took a sample of eight cars of this model and collected the following information on the ages (in years) and prices (in hundreds of dollars) of these cars.

Age	8	3	6	9	2	5	6	3
Price	17	94	51	20	148	44	38	98

Compute the coefficient of determination.

Round your answer to two decimal places.

The coefficient of determination is ??????.

Answer 1

Solution :

X	Y	XY	X^2	Y^2
8	17	136	64	289
3	94	282	9	8836
6	51	306	36	2601
9	20	180	81	400
2	148	296	4	21904
5	44	220	25	1936
6	38	228	36	1444
3	98	294	9	9604

n	8
sum(XY)	1942.00
sum(X)	42.00
sum(Y)	510.00
sum(X^2)	264.00
sum(Y^2)	47014.00
Numerator	-5884.00
Denominator	6353.91
r	-0.9260
r square	0.8576
Xbar(mean)	5.2500
Ybar(mean)	63.7500
SD(X)	2.5000
SD(Y)	45.9226
b	-16.9080
a	152.5172

The coefficient of determination is 0.86 .