Graphical Representation of Data with FAQs

Graphical Representation of Data

The graph is an organized representation of numerical data. It is easy to understand information with the help of these representations. This process being precise and versatile makes data analysis easier. This Graphical representation displays the relation between data, information and concepts in the form of a diagram.

A graph is a type of chart or diagram in which data is plotted as variables across different axes. There are various types in which data can be represented using graphs. 

The different types of graphical representation are:

1. Line Graphs
2. Bar Graph
3. Histogram
4. Pictograph
5. Pie Graph
6. Frequency Table. 
7. Frequency Polygon

Let’s discuss these graphs in detail.

Types of Graph

1. Line Graph

The graph is used to represent continuous data and is used for predicting future events. It can also be termed a linear graph. While plotting data dots are marked and then they are connected using straight lines.

Line Graph

The line graph represents the sale of cars by a motor vehicle company for the years 2010 to 2015. Here the x-axis represents the time interval in years and the y-axis represents the number of cars sold.

2. Bar Graph

A bar graph represents data in the form of rectangular bars on the axis. The height of the bar represents the value or the quantity. The bar graph represents the total marks obtained by students in a class for that term.

Bar Graph

3. Histogram

The histogram also uses bars for data representation but in this case, the frequency of numerical data is organized into intervals. The intervals are equal and continuous, i.e., all bars have the same width. The graph below shows the different ranges of heights of students and the length of the bar denotes the total number of students whose height belong to that range.

Histogram

4. Pictograph

Pictograph is the easiest way to represent data in a pictorial manner by using symbols or images, where the symbol or image represents a particular quantity of objects. The pictograph below shows the favourite treats that Sneha has. The number of treats is denoted by the picture of the object.

Pictograph

5. Pie Graph

In this representation, a circular chart is used and numerical information is represented as slices or in fractions. The whole circle represents 100%. The various categories occupied are marked as per their percentage. It is also called a Circle Graph.

Pie Chart

The pie chart shows the percentage of money used in different ways from total monthly expenses.

6. Frequency Distribution Table

A frequency distribution table is a chart that shows the number of times an event has occurred, i.e., frequency of occurrence.

7. Frequency Polygon

A frequency polygon is a type of graphical representation in which the mid-points of each class interval are connected using straight lines. It is usually drawn along with a histogram, but it can be drawn without it too.

General Rules of Graphical Representation

There are certain rules that should be followed to effectively represent data in graphical format, these rules are:

• Giving an appropriate title to the graph, so that the subject of representation is indicated clearly.
• The measurement unit should be mentioned clearly to avoid confusion.
• A proper scale should be selected so that data representation is accurate.
• An index should be maintained to indicate the scale, colour usage information, etc., to interpret the graph easily. 
• The graph should be represented in such a manner that data can be easily visualized and understood.

Principles of Graphical Representation

Algebraic principles are taken into consideration while plotting graphs. Usually, the graph is represented along two axes, namely the x-axis and the y-axis. The point where the two axes intersect is known as the origin, usually represented as ‘O’. The values on the axes can be both positive and negative. For the plotting across the x-axis positive value is considered towards the right from the origin and negative towards the left of the origin. In the case of the y-axis, positive values lie above the origin and negative values lie below the origin. This can be understood from the graph below: 

Advantages of Graphical Representation

The graphs make data interpretation a lot easier. Following are some more advantages of graphs: 

• The graphical representation makes the data visualization easy. 
• Data can be compared for different periods in a short time.
• A large amount of data can be viewed in a short space and at one instance.