Question

Which is most likely the correlation coefficient for the set of data shown?

–0.65
–0.19
0.19
0.75

Answer 1

I don’t see the scatterplot or the data — I need that to pick the best value. Could you either attach the plot or paste the (x,y) pairs?

If you can’t, here’s how to choose/compute the correlation:

Quick visual rules
- Sign: if the cloud slopes downward, the correlation is negative; upward → positive.
- Magnitude: how tightly points cluster around a line
- |r| ≈ 0–0.3: very weak/none
- |r| ≈ 0.3–0.7: moderate
- |r| ≈ 0.7–1.0: strong

So from your choices:
- –0.65 → moderate-to-strong negative
- –0.19 → very weak negative
- 0.19 → very weak positive
- 0.75 → strong positive

Compute exactly
- Excel/Sheets: =CORREL(rangeX,rangeY)
- Python: import numpy as np; np.corrcoef(x,y)[0,1]
- Hand: r = Σ(xi−x̄)(yi−ȳ) / ((n−1) sx sy)

Send the plot or data and I’ll pick the best option.