Question

1) For each of the six scatterplots, estimate the value of the correlation coefficient. rri 43 Nytt (0) (b) (c) (d) Solution:

Answer 1

I think you forgot to give options for the answer, because otherwise you must provide the data for finding correlation. Anyway I give you the possible answer by some data points that shows same nature as the plots you provided. If there is any additional information please comment, I will give you answer.

I give you answers based on the following plots, here I use R software for calculation.

a)It shows strong negative correlation. That is 0.7<correlation<1.

b)It shows moderately strong positive correlation. That is 0.5<correlation<0.8

c)It shows very strong positive correlation. That is 0.9<correlation<1.

d)It shows week positive correlation. That is 0<correlation<0.2.

e)It shows week negative correlation. That is -0.4<correlation<0

f)It shows strong negative correlation. That is -1<correlation<0.8

(a) x1=C(1,2,3,4,5,6,7,8,9,10,11,1,2,3,4,5,6,7,8,9,10,11) y1=c(14,12,9,8,8.2,8.3,8.5,7,4,2,1,14,11,9,7,8.2,8,8,7,3,1,1) plot(x1, y1) 14 O OO 8 10 o 8 8 y1 - 9 4 OO 2 - 2 4 6 8 10 x1 cor(x1, y1) ## [1] -0.9323859 (b) y2=C(9,4,1,0,1,4,9,16,25,36,49,11,5,1,0,1,4,9,14,22,31,49) plot(x1, y2)

50 O 40 30 y2 ܘܘ OO 20 oo 은 18 o 8 O o 0 O 2 4 6 8 10 x1 cor (x1,72) ## [1] 0.7988189 (c) y3=C(1,2,3,4,5,6,7,8,9,10,11,0,1,2,3,4,5,6,7,8,9,10) plot(x1, y3)

10 OO 8 co OO y3 0 0 4 2 0 0 0 2 4 6 8 10 X1 cor(x1,y3) ## [1] 0.9877296 (d) y4=C(7,6,5,4,5,6,7,8,7,6,5,5,6,5,7,4,5,6,7,6,5,6) plot(x1,74)

00 7 O o O y4 9 O o 1 O O O O 5 O o 4 2 4 9 8 10 X1 cor(x1,74) ## [1] 0.1677051