Question

A value of -1 for the coefficient of correlation between two variables means that the two variables are ________________.

a)somewhat strongly related

b)weakly related

c)perfectly related

d)very weakly related

e)not related at all

2) If the correlation coefficient between variables X and Y is roughly zero, then ______.

a)Y is independent of X

b)Y is dependent on X

c)there is a linear correlation between Y and X

d)Y is not necessarily independent of X

e)Y is caused by X.

3) People in the aerospace industry believe the cost of a space project is a function of the mass of the major object being sent into space. Use the following data to develop a regression model to predict the cost of a space project by the mass of the space object. Determine r² and s_e.

Weight (tons)	Cost ($ millions)
1.897	$ 53.6
3.019	184.9
0.453	6.4
0.971	23.5
1.058	33.1
2.100	110.4
2.385	104.6

*(Do not round the intermediate values. Round your answers to 4 decimal places.)
**(Round the intermediate values to 4 decimal places. Round your answer to 3 decimal places.)

fill in the blank

ŷ = () + ()

r2 =

se =

Answer 1

Ans a )_A value of -1 for the coefficient of correlation between two variables means that the two variables are c)perfectly related

2) If the correlation coefficient between variables X and Y is roughly zero, then ______.

a)Y is independent of X

Simple Linear Regression Analysis
Regression Statistics
Multiple R	0.9521
R Square	0.9065
Adjusted R Square	0.8878
Standard Error	21.0780
Observations	7
ANOVA
	df	SS	MS	F	Significance F
Regression	1	21547.3807	21547.3807	48.4994	0.0009
Residual	5	2221.4078	444.2816
Total	6	23768.7886
	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%
Intercept	-38.7124	18.0116	-2.1493	0.0843	-85.0126	7.5878
Weight (tons)	66.2700	9.5159	6.9641	0.0009	41.8087	90.7314

ŷ = -38.7124 +66.27 x

r2 =0.9065

se =21.078