The limit of multiple correlation coefficient R 1.23 are:
0 to 1
The multiple correlation coefficient \(R_{1.23}\) is the simple correlation between \(X_{1}\) and its best linear predictor \(\hat X_{1}\) based on \(X_{2}, X_{3}\). Because the predicted values are scaled to move in the same direction as \(X_{1}\), this correlation is never negative.
Equivalently, \(R^{2}\) is a proportion of variance explained, so \(0\le R^{2}\le 1\) and therefore \(0\le R\le 1\). The range \(-1\) to \(1\) belongs to the simple correlation \(r\), not \(R\). Hence the limits are 0 to 1.
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:
The coefficient of correlation between two variables X and Y is 0.48. The covariance is 36. The variance of X is 16. The standard deviation of Y is:
If the regression line of Y on X is Y = 30 - 0.9X and the standard deviations are S x= 2 and S y= 9, then the value of the correlation coefficient r xy is :
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:
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:
Consider two exponentially distributed random variables X and Y, both having a mean of 0.50. Let Z = X + Y and r be the correlation coefficient between X and Y. If the variance of Z equals 0, then the value of r is _______ (round off to 2 decimal places).
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