What are merits and demerits of dot method?

Merits of Dot Method:

1. This method is better than any other methods of showing distribution because of its accuracy. The distribution of dots is similar to the commodity shown by them.

2. This is the best method for showing the absolute figures.

3. It provides a better visual effect and is more useful than the other methods of showing distribution.

4. We can have an idea of the figures shown on the map by counting the dots.

5. A dot map can be converted into choropleth or isopleth map but choropleth and isopleth maps can not be trasferred into a dot map.

6. We do not have to look at the index time and again (as in case of choropleth maps) the dots maps can be easily read.

7. More than one element can be shown on a single map by using multiple dot method.

Demerits of Dot Method:

1. It requires a good deal of practice to draw dot maps.

2. This is useful for absolute figures only. Relative figures such as density of population, proportion of agricultural land to total land etc. cannot be shown by dot method.

3. The dot method loses much of its significance if the data are not available for small divisions of area.

4. In addition to the base map with administrative boundaries, we need maps showing relief, climate, soils, vegetation, water-bodies etc. for preparing a dot map. These maps are often not readily available.

5. It is almost impossible to draw a perfect dot map in the absence of complete geographical knowledge of the area and knowledge of the element to be shown.

6. A dot on the map covers 2 to 5 times the actual area on the ground. This gives erroneous picture of the distributional pattern. This exaggeration is about hundred times in case of small and very small maps which further adds to distortion.

7. It is difficult to detect the errors made by the cartographer in placing the dots on a dot map.