Whenever a problem is presented visually it becomes easier for a person to understand it and attempt solution of it. Similarly when the data is presented pictorially (graphically) it becomes easier for people to understand the data. People can easily silent feature of data and interpretation becomes bit more easily.
There are many ways to represent data graphically: a) Bar Graph b) Histograms c) Frequency Polygons d) Ogive e) Pictographs f) Pie Charts Bar Graphs: Bar graph is graphical representation of frequency distribution of ungrouped data Construction of Bar Graphs:
Step 1: We draw 2 perpendicular lines on graph paper and we call them vertical and horizontal axis.
Step 2: Along the horizontal axis(X) we take the values of variables and on vertical axis(Y) we take frequencies.
Step 3: Along the X axis we choose equal width of bars as per the availability of space
. Step 4: Choose a suitable scale to determine height of bar as per the space availability. Step 5: Calculate the heights of bars according to the scale chose and draw the bars. Step 6: Mark the axes with proper labeling.
Histogram and frequency Polygon: Histogram is graphical presentation of grouped frequency distribution. Histogram includes rectangular bars having no space between them. Class intervals are taken on the X axis and respective frequencies on the Y axis taking suitable scale. For each class rectangle is made with width as class interval and height as class frequency. A frequency polygon is made by joining the mid points of the tops of adjoining rectangles.
The mid points of the first and the last rectangles are joined to the midpoints of the classes preceding and succeeding respectively at zero frequency to complete polygon. Ogive: An ogive (a cumulative line graph) is the best when someone has to the total at any given time.
The relative slopes from point to point will indicate greater or lesser increases. For example the steeper slope says that it is greater increase while less steeper slope indicates gradual increase or lesser increase. Pie chart: Pie chart is circular chart divided in to sectors explaining proportions. Pie chart is commonly used in business purpose to explain data in more details.
Pictographs: Pictographs are ideograms that signify its meaning through pictures. Pictographs are commonly used in writing where pictures can be more effective to explain things in detail. Graphical presentation is always preferred everywhere as these are easily explainable and one can easily do the actual analysis by going through it. It’s always better to use graphical methods as being employed in a company I always prefer to make presentation using PIE charts as it makes presentation impressive and self-explanatory. In most of the seminars and presentation people always take help of these charts to prove their point.