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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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From the data of 7 pairs of observations on X and Y, following results are obtained.
∑(xi - 70) = - 35, ∑(yi - 60) = - 7,
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bYX = 2.6 and bXY = `1/2.6`
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| 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)
| Sales | Adv. Exp. | |
| Mean | 40 | 6 |
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Estimate the likely sales for a proposed advertisement expenditure of ₹ 10 crores.
From the two regression equations, find r, `bar x and bar y`. 4y = 9x + 15 and 25x = 4y + 17
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| ADVERTISEMENT (x) (₹ in lakhs) |
DEMAND (y) (₹ in lakhs) |
|
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| Variance | 9 | 144 |
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Regression coefficient of x on y = – 0.3
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