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Question
State whether the following statement is True or False:
Corr(x, x) = 0
Options
True
False
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Solution
False
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Bring out the inconsistency in the following:
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| X | Y | |
| Mean | 85 | 90 |
| S.D. | 5 | 6 |
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The following data about the sales and advertisement expenditure of a firms is given below (in ₹ Crores)
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| Sales | Adv. Exp. | |
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In a partially destroyed laboratory record of an analysis of regression data, the following data are legible:
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| X | Y | |
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| Variance | 150 | 165 |
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The equations of two regression lines are 10x − 4y = 80 and 10y − 9x = − 40 Find:
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If bYX = − 0.6 and bXY = − 0.216, then find correlation coefficient between X and Y. Comment on it.
Choose the correct alternative:
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Choose the correct alternative:
If the regression equation X on Y is 3x + 2y = 26, then bxy equal to
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The following data is not consistent: byx + bxy =1.3 and r = 0.75
State whether the following statement is True or False:
If u = x – a and v = y – b then bxy = buv
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For a certain bivariate data of a group of 10 students, the following information gives the internal marks obtained in English (X) and Hindi (Y):
| X | Y | |
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If r = 0.6, Estimate x when y = 16 and y when x = 10
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`
Mean of x = 25
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`sigma_y` = 3
r = 0.5
byx = `square`
bxy = `square`
when x = 10,
`y - square = square (10 - square)`
∴ y = `square`
| x | y | xy | x2 | y2 |
| 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` |
bxy = `square/square`
byx = `square/square`
∴ Regression equation of x on y is `square`
∴ Regression equation of y on x is `square`
