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प्रश्न
Find the coefficient of correlation for the following data:
| X | 35 | 40 | 60 | 79 | 83 | 95 |
| Y | 17 | 28 | 30 | 32 | 38 | 49 |
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उत्तर
| X | Y | dx = X − 65 | dy = Y − 32 | dx2 | dy2 | dxdy |
| 35 | 17 | − 30 | − 15 | 900 | 225 | 450 |
| 40 | 28 | − 25 | − 4 | 625 | 16 | 100 |
| 60 | 30 | − 5 | − 2 | 25 | 4 | 10 |
| 79 | 32 | 14 | 0 | 196 | 0 | 0 |
| 83 | 38 | 18 | 6 | 324 | 36 | 108 |
| 95 | 49 | 30 | 17 | 900 | 289 | 510 |
| 392 | 194 | 2 | 2 | 2970 | 570 | 1178 |
`bar"X" = 392/6` = 65.33
`bar"Y" = 194/6` = 32.33
Coefficient of correlation
r(X, Y) = `("N"sum"dxdy" - (sum"dx")(sum"dy"))/(sqrt("N"sum"dx"^2 - (sum"dx")^2) xx sqrt("N"sum"dy"^2 - (sum"dy")^2))`
= `(6(1178) - 2(2))/(sqrt(6(2970) - 4) xx sqrt(6(570) - 4))`
= `7064/(sqrt17816 xx sqrt3416)`
= `7065/((133.48) (58.45))`
= `7064/7801.91`
= 0.906
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संबंधित प्रश्न
Calculate the coefficient of correlation for the ages of husbands and their respective wives:
| Age of husbands | 23 | 27 | 28 | 29 | 30 | 31 | 33 | 35 | 36 | 39 |
| Age of wives | 18 | 22 | 23 | 24 | 25 | 26 | 28 | 29 | 30 | 32 |
Calculate the coefficient of correlation between X and Y series from the following data.
| Description | X | Y |
| Number of pairs of observation | 15 | 15 |
| Arithmetic mean | 25 | 18 |
| Standard deviation | 3.01 | 3.03 |
| Sum of squares of deviation from the arithmetic mean | 136 | 138 |
Summation of product deviations of X and Y series from their respective arithmetic means is 122.
Calculate the correlation coefficient for the following data.
| X | 25 | 18 | 21 | 24 | 27 | 30 | 36 | 39 | 42 | 48 |
| Y | 26 | 35 | 48 | 28 | 20 | 36 | 25 | 40 | 43 | 39 |
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| X | 78 | 89 | 96 | 69 | 59 | 79 | 68 | 62 |
| Y | 121 | 72 | 88 | 60 | 81 | 87 | 123 | 92 |
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