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If the sign of the correlation coefficient is negative, then the sign of the slope of the respective regression line is ______
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Solution
negative
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Choose the correct alternative:
If r = 0.5, σ_{x} = 3, `σ_"y"^2` = 16, then b_{yx} = ______
Choose the correct alternative:
If r = 0.5, σ_{x} = 3, σ_{y}^{2} = 16, then b_{xy} = ______
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State whether the following statement is True or False:
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The equations of the two lines of regression are 6x + y − 31 = 0 and 3x + 2y – 26 = 0. Find the value of the correlation coefficient
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Mean of x = 53
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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`
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`x - square = square (25 - square)`
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∴ b_{yx} = `square/square`
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x | y | xy | x^{2} | y^{2} |
6 | 9 | 54 | 36 | 81 |
2 | 11 | 22 | 4 | 121 |
10 | 5 | 50 | 100 | 25 |
4 | 8 | 32 | 16 | 64 |
8 | 7 | `square` | 64 | 49 |
Total = 30 | Total = 40 | Total = `square` | Total = 220 | Total = `square` |
b_{xy} = `square/square`
b_{yx} = `square/square`
∴ Regression equation of x on y is `square`
∴ Regression equation of y on x is `square`
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|b_{xy} + b_{yz}| ≥ ______.