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Question
State whether the following statement is True or False:
If bxy < 0 and byx < 0 then ‘r’ is > 0
Options
True
False
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Solution
False
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RELATED QUESTIONS
For bivariate data. `bar x = 53`, `bar y = 28`, byx = −1.2, bxy = −0.3. Find the correlation coefficient between x and y.
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From the data of 7 pairs of observations on X and Y, following results are obtained.
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The following data about the sales and advertisement expenditure of a firms is given below (in ₹ Crores)
| Sales | Adv. Exp. | |
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Coefficient of correlation between sales and advertisement expenditure is 0.9.
What should be the advertisement expenditure if the firm proposes a sales target ₹ 60 crores?
In a partially destroyed laboratory record of an analysis of regression data, the following data are legible:
Variance of X = 9
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The following results were obtained from records of age (X) and systolic blood pressure (Y) of a group of 10 men.
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| Variance | 150 | 165 |
and `sum (x_i - bar x)(y_i - bar y) = 1120`. Find the prediction of blood pressure of a man of age 40 years.
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Choose the correct alternative:
If byx < 0 and bxy < 0, then r is ______
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DEMAND (y) (₹ in lakhs) |
|
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Obtain the two regression lines:
| Production (X) |
Demand (Y) |
|
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| Variance | 25 | 36 |
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