Diagrams Graphs

The question is how to differentiate a diagram from a graph. Though there is no clear-cut demarcation between the two. The following points of difference may be kept in mind:

1. For constructing a graph we normally make use of graph paper whereas a diagram is normally constructed on plain paper. In another words a graph shows mathematical relationship between two variables while a diagram does not.

2. The diagrams are most attractive to the eye and as such are best suited for publicity & propaganda. it do not add anything to the meaning of  data and therefore, form the point of view of a statistician or research worker they are not helpful in analysis; Graphs, on the other hand, are very much used by the statistician and the research worker in analysis. In fact, nowadays it is difficult to find any research work without the graphic support.

For representing the frequency distributions and time series, graphs are more proper than diagrams. In fact, for presenting the frequency distributions diagrams are rarely used. They are attractive to the eye, figures are dry but the diagrams delight the eye. For this reason diagrams create big interest than cold figures. As diagrams have attraction value, they are very popular in conferences, exhibitions fairs, board meetings & public functions.

Comparison of tabular and diagrammatic presentation:

The Data may be represented in the form of tables as well as diagrams & graphs. Both forms of presentation have their own usefulness for particular purposes; and hence the choice of the form of presentation must be made with due thought and care. The following points may be kept in mind:

1. The Tables contain precise figures whereas diagrams give only an approximate idea. The exact values can be read from a table.

2. More information can be represented in one table than either in one graph or diagram.

3. Tables usually need much close reading and more difficult to interpret than diagrams.

4. The Graphs and diagrams have a visual appeal and therefore more impressive to laymen.