The coefficient of correlation between x and y is 0.6. Their covariance is 4.8 and var(x)=9 . Then σy =
8/3
3/8
8/9
9/8
The lines of regression of a set of data are 8x-10y+66 = 0, 40 x -18y = 214. The variance of x is 9. Then the mean value of x and y are
15,16
13,17
14,16
15,17
The regression lines are x =0.49 y and y = 0.81 x . The coefficient of correlation is
6.3
0.63
63
None of these.
If bxy is positive then byx is
Positive
Negative
Can be any
The regression coefficients are -0.8 and -0.8. The coefficient of correlation is
0.64
0.8
-0.8
The limits of spearman's rank correlation (R) coefficient is
-∞<R<∞
0 ≤ R<∞
-1≤R≤0
-1≤R≤1
In the case of perfect correlation between x and y, the number of regression lines is
0
1
2
More than 2
The coefficient of correlation is independent of
Change of origin only
Change of scale only
Change of origin and scale
If the two regression lines are x+4y=3 and 3x+y =15, then the value of x for which y = 5 is
3/10
-17
10/3
1/17
The lines of regressions make angles 300 and 600 with the positive direction of the x-axis . Then the coefficient of correlation between x and y is
-1
√3
1/√3
