Question

Differentiate between choropleth and isopleths methods.

Answer 1

Choropleth and Isopleth maps are two different forms of distributional maps that are used tor represent various geographical elements in a region. At first glance, they may look similar but the methodology behind them is completely different and they also utilize different data. The following table differentiates between the two methods.

	Choropleth method	Isopleth method
1.	Different Geographical variables are represented by either shade of the same colour or by different colors.	The data for the variable under study is demarcated by isolines which are lines joining the places having the same value.
2.	Continuous or varying data can be used for mapping purposes.	Only continuous data is used.
3.	Administrative boundaries define data boundary and hence continuous data may be misrepresented.	Administrative boundaries do not define a data boundary. Data boundary is defined by isolines.
4.	The smallest and largest values of given data are used to classify the data range into acceptable classes.	Places having the same data value determine the drawing of isolines. The range is determined by the difference in these isolines.
5.	Color gradient or patterns allow map interpretation deeper the color higher the value of data under study.	Placement of lines allows map interpretation, the closer the isolines steeper the data distribution.
6.	Mainly used for data like population density, distribution, etc.	Mainly used for continuous data like temperature, rainfall, altitude, etc.