Sketch a scatterplot showing data for which the correlation is [r = -1].

Sketch a scatterplot showing data for which the correlation is [r = -1].

Question
Scatterplots
asked 2020-11-01
Sketch a scatterplot showing data for which the correlation is [r = -1].

Answers (1)

2020-11-02
Since [r = —1], there is a perfect linear relationship between those two variables (i.e. a deterministic relationship) and they have a negative association (one variable tends to decrease as the other increases). For example, the data
[x 1 2 3 4 5 y 13 11 9 7 5]
has a correlation of —1 since it follows the line [y = 15— 2x] (which is strictly decreasing function, so the association is negative). Here is a picture of the data:
image
Result:
For example, a set of data
[x 1 2 3 4 5 y 13 11 9 7 5]
has a correlation -1.
0

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