<h5 id="representation-of-data">Representation of Data</h5> <ul> <li>Data represents properties of phenomena and is collected from various sources.</li> <li>Geographers, economists, resource scientists, and decision-makers use data in their work.</li> <li>Data can be presented in tabular or graphic/diagrammatic form for easy understanding.</li> <li>Representation of data through visual methods like graphs, diagrams, maps, and charts helps identify patterns and makes comparisons easier.</li> <li>Graphic representation of data enhances understanding and creates a lasting impression on the mind.</li> </ul> <p>======</p> <h5 id="general-rules-for-drawing-graphs-diagrams-and-maps">General Rules for Drawing Graphs, Diagrams and Maps</h5> <ul> <li>Graphs, diagrams, and maps are essential tools for visually representing data and information.</li> <li>To draw a graph, first create a table of data, with the independent variable on the x-axis and the dependent variable on the y-axis.</li> <li>Diagrams can be flowcharts, pie charts, bar graphs, etc., representing various types of data and information.</li> <li>Maps can be physical or political, representing geographical or demographic features.</li> <li>Always label the axes, provide a title, and use a scale for graphs. Similarly, label all parts of the diagrams and maps and provide a legend if necessary.</li> <li>Following these general rules will help ensure that the graph, diagram, or map is clear, accurate, and easy to understand.</li> </ul> <p>======</p> <h5 id="1-selection-of-a-suitable-method">1. Selection of a Suitable Method</h5> <ul> <li>The selection of a suitable method is crucial for graphical representation of data.</li> <li>Different types of data require different methods of representation.</li> <li>Line graphs are suitable for representing data related to temperature or growth of population over time and between different countries/states.</li> <li>Bar diagrams are ideal for showing rainfall or the production of commodities.</li> <li>Dot maps and choropleth maps are used for population distribution, both human and livestock, or the distribution of crop producing areas.</li> </ul> <p>======</p> <h5 id="2-selection-of-suitable-scale">2. Selection of Suitable Scale</h5> <ul> <li>The scale is a measure used to represent data on diagrams and maps.</li> <li>It should be carefully selected considering the entire data set.</li> <li>The scale should not be excessively large or small.</li> <li>An inappropriate scale can lead to misinterpretation or distortion of data.</li> <li>Suitable scale selection ensures accurate and clear representation of data.</li> </ul> <p>======</p> <h5 id="3-design">3. Design</h5> <ul> <li>The design is a crucial aspect of cartography.</li> <li>The title of the diagram/map should clearly indicate the name of the area, reference year of the data used, and the caption. It should be placed at the top center of the map/diagram.</li> <li>A legend or index is essential to explain the colors, shades, symbols, and signs used in the map/diagram. It should be carefully drawn and positioned, usually at the lower left or lower right side of the map sheet.</li> <li>The direction symbol, typically North, should be drawn and properly placed on the final map to orient the representation of the earth’s surface.</li> </ul> <p>======</p> <h5 id="construction-of-diagrams">Construction of Diagrams</h5> <ul> <li>Diagrams and maps represent measurable characteristics of data, such as length, width, and volume.</li> <li>One-dimensional diagrams include line graph, polygon, bar diagram, histogram, and age-sex pyramid.</li> <li>Two-dimensional diagrams include pie and rectangular diagrams.</li> <li>Three-dimensional diagrams include cube and spherical diagrams.</li> <li>Commonly drawn diagrams and maps, along with their construction methods, are line graphs, pie diagram, bar diagrams, wind rose and star diagram, and flow charts.</li> </ul> <p>======</p> <h5 id="line-graph">Line Graph</h5> <ul> <li>The population in India grew at varying rates between 1901 and 2011.</li> <li>There was a significant decrease in population growth from 1911 to 1921.</li> <li>This decrease could be attributed to the aftermath of the 1918-1920 influenza pandemic, which caused significant mortality in India.</li> <li>No specific equations or formulae are provided in the text.</li> <li>The focus is on understanding the reasons for the sudden change in population growth during that period.</li> </ul> <p>======</p> <h5 id="polygraph">Polygraph</h5> <ul> <li>The text provides data on the sex-ratio of selected states in India from 1961 to 2011.</li> <li>Delhi’s sex-ratio was 785 in 1961, 801 in 1971, 808 in 1981, 827 in 1991, 821 in 2001, and 866 in 2011.</li> <li>Haryana’s sex-ratio was 868 in 1961, 867 in 1971, 870 in 1981, 860 in 1991, 846 in 2001, and 877 in 2011.</li> <li>Uttar Pradesh’s sex-ratio was 907 in 1961, 876 in 1971, 882 in 1981, 876 in 1991, 898 in 2001, and 908 in 2011.</li> <li>There is no equation or formula provided in the text.</li> <li>Examples and their solutions are also not included in the text.</li> </ul> <p>======</p> <h5 id="bar-diagram">Bar Diagram</h5> <ul> <li>A bar diagram is composed of columns of equal width, also known as a columnar diagram.</li> <li>The width of all bars or columns should be similar, and they should be placed on equal intervals.</li> <li>Bars can be differentiated by shading them with colors or patterns.</li> <li>The type of bar diagram, such as simple, compound, or polybar, can be chosen based on the data’s characteristics.</li> <li>These rules should be followed while constructing a bar diagram.</li> </ul> <p>======</p> <h5 id="simple-bar-diagram">Simple Bar Diagram</h5> <ul> <li>The text provides data on rainfall in cm measured at unspecified points in time.</li> <li>The measurements are 2.3, 2.1, 3.7, 10.6, 20.8, 35.6, 22.3, 14.6, 13.8, 27.3, 20.6, and 7.5.</li> <li>There are no equations or formulae provided in the text.</li> <li>The text does not contain any examples or their solutions.</li> <li>The data can be used for various statistical analyses or weather pattern studies.</li> </ul> <p>======</p> <h5 id="line-and-bar-graph">Line and Bar Graph</h5> <ul> <li>The text provides monthly precipitation data (in mm) for an unspecified location.</li> <li>The months with the highest precipitation are September (28.9 mm) and May (33.3 mm).</li> <li>The months with the least precipitation are December (15.6 mm), November (19.4 mm), and February (16.7 mm).</li> <li>There is a noticeable increase in precipitation from December to January (15.6 mm to 14.4 mm), and a significant decrease in precipitation from July to August (30.0 mm to 29.4 mm).</li> <li>The overall trend shows a gradual decrease in precipitation from the peak in May to the lowest level in December.</li> </ul> <p>======</p> <h5 id="multiple-bar-diagram">Multiple Bar Diagram</h5> <ul> <li>Multiple bar diagrams are used to compare two or more variables.</li> <li>They can represent data such as proportions of different groups or shares of various categories.</li> <li>An example of multiple bar diagram usage is to show the proportion of males and females in rural and urban populations.</li> <li>Another example is to display the share of canal, tube well, and well irrigation in the total irrigated area across different states.</li> <li>In the given text, an exercise is provided to construct a bar diagram showing decadal literacy rates in India from 1951-2011. However, the actual diagram is not included in the summary.</li> </ul> <p>======</p> <h5 id="compound-bar-diagram">Compound Bar Diagram</h5> <ul> <li>The text provides data from the Economic Survey for the years 2008-09, 2009-10, and 2010-11.</li> <li>For each year, four pieces of data are given: <ul> <li>Expenditure on education as a percentage of Gross State Domestic Product (GSDP).</li> <li>Public expenditure on elementary education as a percentage of GSDP.</li> <li>Plan expenditure on elementary education as a percentage of total Plan expenditure.</li> <li>Total Plan expenditure as a percentage of GSDP.</li> </ul> </li> <li>The values for 2008-09 are 616.2, 110.1, 14.9, and 741.2 respectively.</li> <li>The values for 2009-10 are 677.1, 104.1, 18.6, and 799.8 respectively.</li> <li>The values for 2010-11 are 704.3, 114.2, 26.3, and 844.8 respectively.</li> <li>There are no equations or formulae provided in the text.</li> </ul> <p>======</p> <h5 id="pie-diagram">Pie Diagram</h5> <ul> <li>A pie diagram is a graphical representation of data using a circle divided into sections that correspond to the size of the data subsets.</li> <li>The angle of each variable is calculated using the formula: (Value of given State/Region × 360) / Total Value of all States/Regions or (Percentage of x × 360) / 100 if data is in percentage form.</li> <li>It is also known as a Divided Circle Diagram.</li> <li>The circle’s radius represents the total population in population-related data, and its sub-divisions are shown by corresponding degrees of angle for rural and urban populations.</li> <li>Pie diagrams are not suitable for representing more than a few subsets of data, as too many sections can make the diagram difficult to interpret.</li> </ul> <p>======</p> <h5 id="calculation-of-angles">Calculation of Angles</h5> <ul> <li>The text provides a summary of continents’ angles and their corresponding degrees.</li> <li>Europe is measured at 20.2 units with a degree of 72.72.</li> <li>Africa is measured at 6.5 units with a degree of 23.</li> <li>America is measured at 14.8 units with a degree of 53.</li> <li>Asia and ASEAN are measured at 56.2 units with a degree of 203.</li> <li>Others are measured at 2.3 units with a degree of 8.</li> <li>The total of all continents is 100 units with a degree of 360.</li> </ul> <p>======</p> <h5 id="precautions">Precautions</h5> <ul> <li>The circle in a graph should be of appropriate size, neither too big to fit in the given space nor too small to be illegible.</li> <li>The direction of Indian exports for the year 2010-11 is depicted in Fig. 3.8.</li> <li>The plotting of smaller angles becomes difficult if bigger angles are plotted first, leading to error accumulation.</li> <li>It is recommended to start with smaller angles while plotting.</li> <li>The figure shows the direction of Indian exports, but the specific data or values are not provided in the text.</li> </ul> <p>======</p> <h5 id="flow-mapschart">Flow Maps/Chart</h5> <ul> <li>The text provides distances between different locations in Delhi and adjoining areas.</li> <li>The farthest distance is between Old Delhi and Silampur, which is 3311 units.</li> <li>The shortest distance is between Sarojini Nagar and Pusa Road, which is 86 units.</li> <li>There is no equation or formula provided in the text.</li> <li>Examples and their solutions are not included in the text.</li> </ul> <p>======</p> <h5 id="thematic-maps">Thematic Maps</h5> <ul> <li>Thematic maps are used to understand the patterns of regional distributions or variations of characteristics over space.</li> <li>Required data for creating a thematic map: a. State/District level data about the selected theme b. Outline map of the study area with administrative boundaries c. Physical map of the region (e.g., physiographic map for population distribution)</li> <li>Rules for making thematic maps: a. Carefully plan the drawing of the map b. Include necessary components: name of the area, title of the subject-matter, source of the data and year, indication of symbols, signs, colors, shades, etc., and scale c. Select a suitable method for thematic mapping</li> <li>Examples of thematic maps: population distribution, transportation map using relief and drainage.</li> </ul> <p>======</p>