In bivariate data, we sometimes notice that one of the quantities increases (1, 2, 3...) while the other quantity decreases (20, 19, 18...). Which phrase best describes this association? would it be no correlation, a perfect correlation,a positive correlation or a negative correlation?

Answers (1)

2020-12-01

Step 1
The direction of the relationship of correlation can be a positive relationship or a negative relationship. If there is tendency for two variables to change in the same direction, as one variable increases, the other variable also tends to increase and vice versa then it is a positive relationship. If there is a tendency for two variables to change in opposite direction, increase in one variable tend to be accompanied by decrease in the other then it is called as a negative relationship.
A correlation or correlation coefficient is a numerical value that measures and describes the relationship between two variables. The sign of correlation (+/-) indicates the direction of the relationship. "+" indicates a positive correlation and "-" indicates a negative correlation. The numerical value of the relation (from 0 to 1) indicates the strength of the relationship. The type of correlation indicates the form of the relationship.
Step 2
Here, one variable increases, and the other variable decreases.
From the above said points, there is a negative correlation between the variables.

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\(\begin{array}{|c|c|}\hline 11.8 & 7.7 & 6.5 & 6 .8& 9.7 & 6.8 & 7.3 \\ \hline 7.9 & 9.7 & 8.7 & 8.1 & 8.5 & 6.3 & 7.0 \\ \hline 7.3 & 7.4 & 5.3 & 9.0 & 8.1 & 11.3 & 6.3 \\ \hline 7.2 & 7.7 & 7.8 & 11.6 & 10.7 & 7.0 \\ \hline \end{array}\)
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MPa
State which estimator you used.
\(s\)
\(x\)
\(p?\)
\(\tilde{\chi}\)
\(\frac{s}{x}\)
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MPa
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