Which of the following graphical methods of data representation is useful for…

Concept

A graphical method should match the structure of the data. When every observational unit supplies a pair of numerical values, the graph must preserve each pair as one point rather than summarize only one variable or a whole into categories.

Application

Here, the aim is to examine the association between two variables. Plotting one variable on the horizontal axis and the other on the vertical axis places every paired observation at coordinates (x, y); the direction, form, and strength of the point pattern then reveal their association.

Contrast

• An ogive displays cumulative frequency against class boundaries, so it summarizes one distribution.

• A pie chart displays category shares of one total, so it represents composition.

• A histogram displays frequencies across intervals of one quantitative variable, so it represents a distribution.

• A scatter plot retains paired values for two variables, so it displays their joint pattern.

Cross-check and result

If the paired values change together, their points form a visible upward or downward pattern; the other graphs do not preserve both coordinates for each observation. Therefore, the suitable method is the scatter plot.