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How many water bottles do you drink to get though a week? (X) X Bar= 14.3 | Sx =6.988414057 | | |

How many songs do you have on iTunes? (Y) Y Bar= 2813.466667 | Sy = 2843.445782 |

Co-variance S(xy)

= Sum of (x-xbar)(y-ybar)/(n-1)

= 85023.8/29

=2931.85

R(xy) = S(xy)/(Sx)(Sy) = 2931.85/ (6.99)(2843.44)

= 0.1475

There is not much correlation between the two variables

Yhat= b1x-b0 b1 = sum (x-xbar)(y-ybar)/sum(x-xbar)^2 b1 = 85023.8 / 1416.3 b1 = 60.03

b0 = y bar- (b1*x bar) b0 = 2813.466667- (858.429)

Yhat = 60.03x+ 1955.041

SST = SSE + SSR

Sum of (y-ybar)^2 = Sum of (y-yhat)^2 + Sum of (yhat - ybar)^2

234,470,333.5 = 229,366,156+ 5,103,779.955

234,470,333.5 = 234,470,333.5

R square= SSR/SST = 5,103,779.955/ 234,470,333.5 = 0.022

Only about 2.2% of y can v=be explained by the behavior of x

Ho : B1=0

Ha : B1 not = 0…...

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