Question

23. Define correlation. 24. What is correlation strength? Provide examples of different strengths. 25. What is meant by the direction of the correlation? 26. Draw and explain a perfect positive correlation and a perfect negative correlation 27, Graph given correlations, labelling the axis and providing a title for the graph and an explanation of the correlation

Answer 1

23)

Correlation is a statistical measure that indicates the extent to which two or more variables fluctuate together. A positive correlation indicates the extent to which those variables increase or decrease in parallel; a negative correlation indicates the extent to which one variable increases as the other decreases.

24)

as a rule of thumb, the following guidelines on strength of relationship are often useful (though many experts would somewhat disagree on the choice of boundaries).

Value of r	Strength of relationship
-1.0 to -0.5 or 1.0 to 0.5	Strong
-0.5 to -0.3 or 0.3 to 0.5	Moderate
-0.3 to -0.1 or 0.1 to 0.3	Weak
-0.1 to 0.1	None or very weak

25)

In general, r > 0 indicates a positive relationship, r < 0 indicates a negative relationship and r = 0 indicates no relationship (or that the variables are independent of each other and not related). Here r = +1.0 describes a perfect positive correlation and r = -1.0 describes a perfect negative correlation