Chapter : 3
What Are Graphical Representation Of Data ?
The line graphs are usually drawn to represent the time series data related to the temperature, rainfall, population growth, birth rates and death rates.
Multiple Bar Diagram
Multiple bar diagrams are constructed to represent two or more than two variables for the purpose of comparison.
Compound Bar Diagram
When different components are grouped in one set of variable or different variables of one component are put together, and a compound bar diagram makes their representation. Different variables are shown in a single bar with different rectangles in this method.
Maps depicting quantitative variables like areas receiving more than 200 cm, 100 to 200 cm, 50 to 100 cm and less than 50 cm of rainfall are referred as quantitative maps. These maps are also called statistical maps.
A map depicting non-measurable characteristics in the distribution of information such as a map showing high and low rainfall-receiving areas, is called non-quantitative map. These maps are also called qualitative maps.
The dot maps are drawn to show the distribution of phenomena such as population, cattle, types of crops, etc. The dots of the same size as per the chosen scale are marked over the given administrative units to highlight the patterns of distribution.
The choropleth maps are also drawn to depict the data characteristics as they are related to the administrative units. These maps are used to represent the density of population, literacy/growth rates, sex-ratio, etc.
The word ‘Isopleth’ is derived from Iso means equal, and pleth means lines. Thus, an imaginary line, which joins the places of equal values, is referred as Isopleth. The more frequently drawn Isopleths include Isotherm (equal temperature), Isobar (equal pressure), Isohyets (equal rainfall), Isonephs (equal cloudiness), Isohels (equal
sunshine), contours (equal heights), Isobaths (equal depths), Isohaline (equal salinity), etc.