Question

Use the given data to find the equation of the regression line. Examine the scatterplot and identify a characteristic of the data that is ignored by the regression line.

X 11 8 11 8 12 13 7 4 12 6 5

Y 7.58 6.69 13.24 7.32 7.62 8.52 6.09 5.15 8.13 6.15 5.52

Answer 1

We have to find a scatter plot, by using excel we can find easily.

-First, enter all data into excel

Select all data ----------> Click on Insert --------> Scatter ------->Click on first graph
We get

Ther is a positive correlation between x and y.

Now we have to find the equation of the regression line.

The regression equation is y = a + bx

Here a is intercept and b is the slope.

= 8.8182

= 7.4555

	X	Y	XY	X^2
	11	7.58	83.38	121
	8	6.69	53.52	64
	11	13.24	145.64	121
	8	7.32	58.56	64
	12	7.62	91.44	144
	13	8.52	110.76	169
	7	6.09	42.63	49
	4	5.15	20.6	16
	12	8.13	97.56	144
	6	6.15	36.9	36
	5	5.52	27.6	25
Total	97	82.01	768.59	953

So the equation of the regression line is = 3.3541 + 0.4651*x