____________________ visually presents the nature of association without giving any specific numerical value.

Scatter diagram

The correct answer is Option 3: Scatter diagram

Three important tools used to study correlation are scatter diagrams, Karl Pearson’s coefficient of correlation and Spearman’s rank correlation.

A scatter diagram visually presents the nature of association without giving any specific numerical value.

A numerical measure of linear relationship between two variables is given by Karl Pearson’s coefficient of correlation. A relationship is said to be linear if it can be represented by a straight line.

Spearman’s coefficient of correlation measures the linear association between ranks assigned to individual items according to their attributes. Attributes are those variables which cannot be numerically measured such as intelligence of people, physical appearance, honesty, etc.