Cartograms

Population Density Map
Choropleth map are the basic tool to an urban geographers with the help of this quantitative area maps spatial distribution or density can easily be represented to find out the density difference of different ward of Koch Bihar Municipality. We chose this technique and the intervals simply by the historical character. With the help of this technique we may draw a conclusion regarding economic variation and the variety of affinities among the wards. This density map related as they are to the administrational unit reveal only average distribution vary after over considerable areas.

Calculation
Ward No.	Area in sq Km.	No. of Population	Density/ Sq. Km.
1	0.48	4541	9460.42
2	0.12	1912	15933.33
3	0.22	4143	18831.82
4	0.36	3244	9011.11
5	0.26	3728	14338.46
6	0.22	3577	16259.09
7	0.16	1736	10850.00
8	0.62	6051	9759.68
9	1.34	4962	3702.99
10	0.88	4788	5440.91
11	0.22	3810	17318.18
12	0.34	4330	12735.29
13	0.36	3255	2041.67
14	0.20	3790	18950.10
15	0.16	3973	24831.25
16	0.30	4175	1391.67
17	0.34	2461	7238.24
18	0.46	3972	8634.78
19	0.80	4177	5221.25
20	0.64	4184	6537.50
Case study: 4541/0.48=9460.42

With Transparent Municipal Map 

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Inter Censal Change of Population

Decadal variation is the variation of population per ten years or decade and expressed in percentage (%). The decadal change indicates the scope of activity as well as carrying capacity in a town, in a district or in a manner. Lastly world also has a specific decade period. The decadal variation of population also known as Inter Censal Change of Population or Percentage variation. For preparing decadal variation or percentage variation the map is drawn by the choropleth or shade method and also done by the chorocromatic method.

Calculation
State	Population in 1991	Population in 2001	Variation (%)
Darjeeling	1299919	1605900	23.54
Jalpaiguri	2800543	3403204	21.52
Koch Bihar	2171145	2478240	14.15
N. Dinajpur	1897045	2441824	28.72
S. Dinajpur	1230608	1502647	22.11
Malda	2637032	3290160	24.77
Mursidabad	4740149	5863717	23.70
Birbhum	2555664	3012546	17.88
Barddhaman	6050605	6919698	14.36
Nadia	3852097	4603756	19.51
N. 24 Pargana	7281881	9830295	22.64
S. 24 Pargana	5715030	6909015	20.89
Hugli	4355230	50400	15.72
Bankura	2805065	3191822	13.79
Piuruliya	2224577	253233	13.96
Mednapur	8331912	9638473	15.68
Howrah	3729644	4274010	14.60
Kolkata	4399819	4580544	4.11
Case study: Inter Censal Change = {(1605900-1299919)/ 1299919}x 100 = 23.54

With Transparent State Map 

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Size of Urban Center by Sphere Method 

Sphere is a tree dimensional diagram and it is also called volume diagram. Sphere has a great disadvantage in data, can difficult to calculate the root of the figure involved. But in the point of view of data representation of an urban centre sphere has a great advantage in data can easily depicted by sphere.  The formula used to find out the radius of the any sphere are- 

Name of the urban Centre	Population	Radius	Acc. to Scale
Greater Mumbai	1636084	157.49	1.57
Kolkata	13216546	146.66	1.46
Delhi	12791458	154.07	1.45
Chennai	6424624	115.31	1.15
Bangalore	5686844	110.72	1.10
Hyderabad	5533640	109.71	1.10
Ahmadabad	4519278	102.55	1.02
Pune	3755525	96.42	0.96
Surat	2811466	87.55	0.87
Kanpur	2690486	86.27	0.86
Graphical Scale	10000000	152.98	1.53
	5000000	133.64	1.34
	2500000	106.07	1.06

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Traffic Flow Map

Traffic flow map shows the nature of degree of concentration of goods, traffic and passengers along different line of communication. It shows the proportion of the total traffic movement during a certain period. A line of uniform thickness may be taken as unit and more such lines may straight without activating from the general direction on the map and scale is also kept more or less through at least along the main line.

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Compound Pyramid

This is special kind of bar diagram where bar are arrange typically in a pyramidal form. In an urban pyramid absolute or percentage distribution of town or cities according to different size class is shown. These types of pyramid have been intensively used by the urban geographers to identify the structural properties of urban system.

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