Elementary Statistics (1+1)

5.1.9 Pictograms

Pictograms are very popularly used in presenting statistical data. They are not abstract presentations such as lines or bars but really depict the kind of data we are dealing with. Pictures are attractive and easy to comprehend and as such this method is particularly useful in presenting statistics to the layman. When pictographs are used data is              represented through a pictorial symbol that is carefully selected.

While constructing a pictograph the following points should be kept in mind :

The pictorial symbol should be self-explanatory. If we are telling a story about aeroplane, the symbol should clearly indicate an aeroplane. The following points should be kept in mind while selecting a pictorial symbol :

a) A symbol must represent a general concept (like man, woman, child, bus) not an individual of the species (not Hitler, Akbar or Dr.Sharma’s car).

b) A symbol should be clear concise and interesting.

c) A symbol must be clearly distinguishable from every other symbol.

d) A symbol should suit the size of paper, ie. It should be neither too small nor too large.

e) Last, but not the least, an artist should use the principles of a good design established by the fine and applied arts when drawing a pictorial symbol.

2) Changes in numbers are shown by more or fewer symbols, not by larger or smaller ones.

3) Pictographs should be simple to understand and convey essential facts.

Merit :

1) Compared with other types of diagrams, pictographs have  greater attraction value and, When the attention of masses is to be drawn such as in exhibitions, fairs, they are very popularly used. They stimulate interest in the information being represented.

2) Facts portrayed in pictorial form are generally remembered longer than facts presented in tables or in non-pictorial charts.

Limitations :

1) They are difficult to construct. Besides, it is necessary to use one symbol to represent a fixed number of units which may create difficulties. Thus if one symbol is representing 10 crore persons, the question is how to represent a population of 31.85 crores. In such a case either the symbol should be proportionately smaller or the figure approximated to 30 crores. In either case, error is introduced.

2) Pictographs give only an overall picture, they do not give minute details. For greater accuracy we should write actual figure under, above or on one side of the symbol.