Question

to determine how strong a correlation is between two variables, we can compute a correlation coefficient or we can check to see if the scatterplot is sloping upward or downward. or we can consider a third variable for the correlation. or we can examine the spread of the scatterplot. or we can see if the dependent variable is different for the experimental group and the control group.

Explanation:

The correlation coefficient is a numerical measure of the strength of the linear relationship between two variables. Checking the upward or downward slope of a scatter - plot only gives the direction of the relationship, not the strength. Considering a third variable affects the nature of the relationship rather than measures its strength. Examining the spread of a scatter - plot doesn't directly measure strength. Comparing dependent variables between experimental and control groups is for assessing the effect of an intervention, not the correlation strength.

Answer:

No correct option provided in the given choices.