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Question
State whether the following statement is True or False:
bxy is the slope of regression line of y on x
Options
True
False
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Solution
False
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The equations given of the two regression lines are 2x + 3y - 6 = 0 and 5x + 7y - 12 = 0.
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The data obtained on X, the length of time in weeks that a promotional project has been in progress at a small business, and Y, the percentage increase in weekly sales over the period just prior to the beginning of the campaign.
| X | 1 | 2 | 3 | 4 | 1 | 3 | 1 | 2 | 3 | 4 | 2 | 4 |
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The equations of two regression lines are 10x – 4y = 80 and 10y – 9x = 40. Then bxy = 0.9
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If the regression equations are 8x – 10y + 66 = 0 and 40x – 18y = 214, the mean value of y is ______
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If n = 6, Σx = 36, Σy = 60, Σxy = –67, Σx2 = 50, Σy2 =106, Estimate y when x is 13
The regression equation of x on y is 40x – 18y = 214 ......(i)
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Solving equations (i) and (ii),
`barx = square`
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∴ byx = `square/square`
∴ bxy = `square/square`
∴ r = `square`
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Complete the following activity to find, the equation of line of regression of Y on X and X on Y for the following data:
Given:`n=8,sum(x_i-barx)^2=36,sum(y_i-bary)^2=40,sum(x_i-barx)(y_i-bary)=24`
Solution:
Given:`n=8,sum(x_i-barx)=36,sum(y_i-bary)^2=40,sum(x_i-barx)(y_i-bary)=24`
∴ `b_(yx)=(sum(x_i-barx)(y_i-bary))/(sum(x_i-barx)^2)=square`
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