Question

Frequent food questionnaires (FFQ) are a simple way to obtain information on the foods individuals consume by asking them questions about typical amounts of food consumed in a day or week or month. A more accurate picture is obtained by obtaining a detailed food diary (DR) for several days, randomly chosen over a certain time period. The data obtained from a frequent food questionnaire can be compared with the food diary to assess the validity of the questionnaire. The data below are for seven individuals who participated in such a study on alcohol consumption.

DR8.26 FFQ1.68
0.83 0
20.13 15.1
11.16 7.49
7.18 12.84
1.76 0
22.66 25.06
A. 0.89
B. -0.89
C. None of the answers are correct
D. 0

Answer 1

Asnwer is A

Explanation:

since the correlation between the FFQ and DR is 0.89

x y xy
`x^(2)`
`y^(2)`

8.26 1.68 13.8768 68. 2276 2.8224

0.83 0 0 06889 0

20.13 15.1 303.963 405.2169 228.01

11.16 7.49 83.5884 124.5456 56.1001

7.18 12.84 92.1912 51.5524 164.8656

1.76 0 0 3.0976 0

22.46 25.06 567.8596 513.4756 628.0036

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∑
`x_(i)` = ∑
`y_(i)` = ∑
`x_(i) y_(i)`= ∑
`x_(i)^(2) y_(i)^(2)`= ∑
`y_(i) ^(2)`=

71.98 62.17 1061.479 1166.8046 1079.8017

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Correlation Coefficient or Pearson Correlation is given by:

the rest calculation is in the attached image