If the multiple correlation coefficient of X 1on X 2and X 3is zero, then:
r12 = 0, r13 = 0
\(R_{1.23}\) is the correlation between \(X_{1}\) and its best linear predictor based on \(X_{2}, X_{3}\). If \(R_{1.23}=0\), no linear combination of \(X_{2}, X_{3}\) correlates with \(X_{1}\).
Using \[R^{2}_{1.23}=\frac{r_{12}^{2}+r_{13}^{2}-2r_{12}r_{13}r_{23}}{1-r_{23}^{2}}=0,\] the numerator must vanish, giving \((r_{12}-r_{13}r_{23})^{2}+r_{13}^{2}(1-r_{23}^{2})=0\). Both squared terms are non-negative, so each is zero, forcing \(r_{13}=0\) and then \(r_{12}=0\).
Hence \(R_{1.23}=0\) requires \(r_{12}=0\) and \(r_{13}=0\).
The coefficients of the regression β X|y and β Y|x , are known, The coefficient of correlation equals:
Which option is correct for the correlation ratio E 2?
Let θ be the angle made by the line of regression of Y on X. If σ Y= 2σ X and the correlation coefficient between X and Y is 0.3, the value θ equals
The multiple correlation coefficient R 1,23 as compared to any simple correlation coefficients between the distinct variable X 1 ,X 2, and X 3is
The correlation coefficient between two variables X and Y is 0.4. The correlation coefficient between 2X and (-Y) will be:
If a data set contains n paired values on two variables x(independent) and y(dependent), then their plot is called:
Suppose r xy is the correlation coefficient between two variables X and Y
where s.d.(X) = s.d.(Y). If θ is the angle between the two regression lines of Y on X and X on Y then:
For an experiment we have the following data set: n = 4, ∑x = a, ∑y = 10, ∑xy = 21, ∑x 2 = 30, ∑y 2 = 30. If the correlation coefficient is -0.8 then the value of a is:
The limit of multiple correlation coefficient R 1.23 are:
If r 12 = +0.80, r 13 = -0.40 and r 23 = -0.56, then the square of multiple correlation coefficient (correct to four decimal places) \(R^2_1{.}{_2}{_3}\) is equal to:
If X ∼ N (0, 1) and Y = X2 then the correlation coefficient r (X, Y) is
Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): If the securities with less than perfect negative correlation between their price movements are combined, portfolio risk can be reduced significantly.
Reason (R): The term with negative correlation has the effect of reducing the computed value of total portfolio risk, given other terms that are positive.
In the light of the above statements, choose the most appropriate answer from the options given below:
The two-regression equation of variable \(\rm{x}\) and \(\rm{y}\) are
\(\rm{y = 0.8x + 9.8}\) and \(\rm{x = 10.2 + 0.6y}\)
The coefficient of correlation between \(\rm{x}\) and \(\rm{y}\) is