Question

Find the value of r and determine if a correlation exists at the indicated level of significance.

Answer 1

α = 0.01

Answer 2

Have never done this not sure of where to start...Help Please

Answer 3

what do you mean be the indicated level of significance?

Answer 4

A. r = 0.9710; Correlation exists.

B. r = 0.9997; Correlation exists.

C. r = 0.9710; Correlation does not exist.

D. r = 0.9971; Correlation exists.

Answer 5

I never done this before thats the question above and the choices to anwser it by

Answer 6

what does the upper a represent or is it an x?

Answer 7

x

Answer 8

\[r=\frac{S _{xy}}{\sqrt{S _{xx}}S _{yy}}\]
\[S _{xx}=\sum_{i=1}^{n}(x _{i}-xbar)^{2}\]
wher xbar is the mean value of x.

Do you want me to continue with more necessary formulas?

Answer 9

:-/ a bit loss...sorry this is my first time working a problem like this

Answer 10

To calculate r you need to set up a table with 7 columns headed:
x, y, x - xbar, y - ybar, (x - xbar)^2, (y - ybar)^2, (x - xbar) * (y _ ybar)

The arithmetic is not difficult

Answer 11

got it !

Answer 12

Great:) Enter the values for x and y in the first two columns. Add up the values for x and for y and divide each total by 4 to find xbar and ybar. When you finish can you please post these values for checking?

Answer 13

@HoneyDarlin How is it going?

Answer 14

I got D r = 0.9971; Correlation exists...not sure if its right but tried my best and my second choice was B

Answer 15

You are right :) r = 0.9971; correlation exists. Good work!

Answer 16

Thanks ;)