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Corr(x, x) = 1
Options
True
False
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Solution
This statement is True.
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RELATED QUESTIONS
For bivariate data. `bar x = 53, bar y = 28, "b"_"YX" =  1.2, "b"_"XY" =  0.3` Find Correlation coefficient between X and Y.
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For a certain bivariate data
X  Y  
Mean  25  20 
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Find the value of the covariance between X and Y, if the regression coefficient of Y on X is 3.75 and σ_{x} = 2, σ_{y} = 8
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b_{xy} and b_{yx} are ______
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If r = 0.5, σ_{x} = 3, `σ_"y"^2` = 16, then b_{yx} = ______
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If r = 0.5, σ_{x} = 3, σ_{y}^{2} = 16, then b_{xy} = ______
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Both the regression coefficients cannot exceed 1
State whether the following statement is True or False:
If b_{xy} < 0 and b_{yx} < 0 then ‘r’ is > 0
State whether the following statement is True or False:
Corr(x, x) = 0
If the sign of the correlation coefficient is negative, then the sign of the slope of the respective regression line is ______
If u = `(x  20)/5` and v = `(y  30)/4`, then b_{yx} = ______
The geometric mean of negative regression coefficients is ______
Given the following information about the production and demand of a commodity.
Obtain the two regression lines:
ADVERTISEMENT (x) (₹ in lakhs) 
DEMAND (y) (₹ in lakhs) 

Mean  10  90 
Variance  9  144 
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What should be the advertising budget if the company wants to attain the sales target of ₹ 150 lakhs?
Given the following information about the production and demand of a commodity.
Obtain the two regression lines:
Production (X) 
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Mean  85  90 
Variance  25  36 
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If n = 5, Σx = Σy = 20, Σx^{2} = Σy^{2} = 90 , Σxy = 76 Find Covariance (x,y)
x  y  `x  barx`  `y  bary`  `(x  barx)(y  bary)`  `(x  barx)^2`  `(y  bary)^2` 
1  5  – 2  – 4  8  4  16 
2  7  – 1  – 2  `square`  1  4 
3  9  0  0  0  0  0 
4  11  1  2  2  4  4 
5  13  2  4  8  1  16 
Total = 15  Total = 45  Total = 0  Total = 0  Total = `square`  Total = 10  Total = 40 
Mean of x = `barx = square`
Mean of y = `bary = square`
b_{xy} = `square/square`
b_{yx} = `square/square`
Regression equation of x on y is `(x  barx) = "b"_(xy) (y  bary)`
∴ Regression equation x on y is `square`
Regression equation of y on x is `(y  bary) = "b"_(yx) (x  barx)`
∴ Regression equation of y on x is `square`
Mean of x = 53
Mean of y = 28
Regression coefficient of y on x = – 1.2
Regression coefficient of x on y = – 0.3
a. r = `square`
b. When x = 50,
`y  square = square (50  square)`
∴ y = `square`
c. When y = 25,
`x  square = square (25  square)`
∴ x = `square`
If b_{yx} > 1 then b_{xy} is _______.