Data Handling

Data handling is the process of systematically collecting, organizing, analyzing, and presenting data to extract useful information and support decision-making. It involves ensuring the accuracy and integrity of data, processing it into a manageable form, and presenting it through clear formats such as charts, graphs, and tables. The goal is to make complex data easier to understand and interpret, ensuring its safe storage and accessibility throughout its lifecycle.

For studying this topic, we also focus on how data is collected or generated for our use from any source. This procedure involves the steps to acquire the data, clean it, and prepare it for analysis and study.

Types of Data

Data can be segregated into two broad categories: Quantitative Data and Qualitative Data.

Quantitative Data

Quantitative Data is data that gives numerical information. It is measurable and quantifiable, and it can be written in terms of numbers, which are amenable to mathematical operations. Quantitative data can be further categorized into:

• Discrete Data: Data that can have definite, distinct values (e.g., number of individuals in a room).
• Continuous Data: Data that can have any value between a range (e.g., height, weight, temperature).

Qualitative Data

Qualitative Data is non-numerical data describing features or qualities. Qualitative Data is descriptive data and cannot be directly measured in terms of numbers. Examples are names, colours, or classes of objects.

➣ Learn the difference the Quatitative and Qualitative data - [Read More]

Important Terms in Data Handling

There are some terms used often in data handling to better understand and deal with data:

1) Data: The set of facts or figures obtained from observations or measurements.

2) Raw Data: Raw and unstructured data collected directly from the source and could require cleaning or formatting.

3) Range: The range is the difference between the largest and smallest value in a set of data. It provides a measure of spread or variability of the data.

4) Statistics: The branch of science that deals with the collection, organization, analysis, interpretation, and presentation of numerical data. It facilitates data-informed decisions.

Steps Involved in Data Handling

Data handling is a methodical process of handling and interpreting data properly. The steps usually consist of-

Purpose: Define and state specifically the purpose or problem. This makes the data handling process dedicated to answering one specific question or resolving a unique problem.

Collection of Data: Collect data pertaining to the set purpose. The accuracy and quality of data gathered play a very important role in significant analysis.

Presentation of Data: Display the gathered data in a simple and easy-to-read manner. It can be in the form of tables, graphs, or marks, based on the complexity of the data.

Graphical Representation of Data: Employ visual aids such as graphs, histograms, and bar charts to represent the data. Graphical representation assists in the easy analysis of trends and patterns in the data.

Analyzing the Data: Scan the data carefully to derive useful information. Statistical techniques or other techniques of analysis are used to derive insights.

Conclusion/Inference: From the analysis, make conclusions or inferences to give a solution or response to the problem statement. This step helps in decision-making or subsequent actions.

Graphical Representation of Data

In data handling, one of the most significant areas is how the data is represented. Proper representation is easier to understand, analyze, and interpret. Among all the ways data can be represented, graphical representation is particularly good at representing trends and patterns effectively and speedily.

• Pictographs or Picture Graphs
• Bar Graphs
• Line Graphs
• Pie Charts
• Scatter Plot

Pictographs

A pictograph is the pictorial representation of any data given to us in written form. It can be said that pictographs used to be the earliest form of communication, since, way back in time, people communicated mostly through pictures with each other, as languages were not present.

Indeed, a pictograph plays a role in our day-to-day life too. For instance, when a friend tells us a story, we start imagining the story in our head, and that makes it both easy to understand and easy to remember for a long time.

Drawing a Pictograph

Let's learn to draw a pictograph with the help of an example.

Example: In a reading competition, three students were participating—Rahul, Saumya, and Ankush. They were supposed to read as many books as they could in an hour. Rahul read 3 books, Saumya read 2 books, and Ankush read 4 books. Draw the pictograph for the information.

Solution:

There are some basic steps to draw a pictograph:

• Decide the particular picture or pictures that are required to represent the data. Make sure that the picture is related to the information for easier memorization.
• Here, a smiley face is used to represent each book read.

• Now, draw the pictures according to the information presented. For example, there will be 3 smiley faces for Rahul, as he completed 3 books in an hour.

Bar Graphs

The graphical representation of any quantity, number, or data in the form of bars is called a Bar graph. With the help of a bar graph, not only does the data look neat, but it is also easier to compare the data given.

Types of Bar Graph

Various types of bar graphs include:

Vertical Bar Graph

These are the most common bar graphs we come across; the bars of grouped data in vertical bar graphs lie vertically. Sometimes, when the data categories have long names, horizontal bar graphs are preferred, since in vertical bar graphs, there is not much space on the x-axis.

An example explaining the concept of a Bar graph is added below:

Example: There are 800 students in a school. And the table for their birthdays in all 12 months is given below. Draw the Vertical Bar graph and answer. who

1. In which month do the maximum number of students have their birthdays?
2. Which two months have the same number of birthdays?
3. In which month do the minimum number of students have their birthdays?

Solution:

The vertical bar graph for the table given in the question will be,

From the Bar graph we can figure out the answer of the questions

1. August is the month in which the maximum number of birthdays occur.(there are 110 students whose birthday come in August)
2. From the graph, we can tell that January and April have equal lengths of bars, which means they have the same number of birthdays.(both have 50 birthdays)
3. The minimum number of birthdays occur in December, as it has the smallest bar (20 students have their birthdays in December).

Horizontal Bar Graph

A horizontal bar graph is a graph where the rectangular bars lie horizontally. In such graphs, the frequency of the data is represented on the x-axis, while the categories of data are shown on the y-axis. These are known as horizontal bar graphs.

Horizontal bar graphs are preferred when the category names are long and there is insufficient space on the x-axis.

Example: In an examination, Reeta appeared for 5 subjects. Her performance is given in the table below: Draw a horizontal bar graph showing the marks she obtained in all the subjects. Also, calculate the overall percentage obtained by her

Solution:

The Horizontal bar graph for the table mentioned in the question,

The overall Percentage obtained by Reeta = \frac{(90+80+95+70+60)}{500}×100

= 79 percent.

Double-Bar Graph

Double-bar graphs are used when two groups of data are required to be represented on a single graph. In a double-bar graph, to represent two groups of data, they are represented beside each other at different heights depending on their values.

Advantages of a points double-bar graph:

• A double-bar graph is helpful when multiple data points need to be represented.
• It helps in summarizing large and big data in an easy and visual form.
• It shows and covers all different frequency distributions.

Example: The table below shows the number of boys and girls in classes 6, 7, 8, 9, and 10. Represent the data on a double-bar graph

Solution:

The double-bar graph for the table given the question,

Line Graphs

A Graph or a line chart visually shows how different things relate over time by connecting dots with straight lines. It helps us see patterns or trends in the data, making it easier to understand how variables change or interact with each other as time goes by.

To make a line graph

We need to use the following steps:

• Determine Variables: The first and foremost step to creating a line graph is to identify the variables you want to plot on the X-axis and Y-axis.

• Choose Appropriate Scales: Based on your data, determine the appropriate scale.

• Plot Points: Plot the individual data points on the graph according to the given data.

• Connect Points: After plotting the points, you have to connect those points with a line.

• Label Axes: Add labels to the X-axis and Y-axis. You can also include the unit of measurement.

• Add Title: After completing the graph, you should provide a suitable title.

Example: Kabir eats eggs each day, and the data for the same is added in the table below. Draw a line graph for the given data

Solution:

Pie Charts

It is one of the types of charts in which data is represented in a circular shape. In a pie chart circle is further divided into multiple sectors/slices; those sectors show the different parts of the data from the whole.

Pie charts, also known as circle graphs or pie diagrams, are very useful in representing and interpreting data

Example: In an office, the data of employees who play various sports is shown in the table below:

Draw a suitable pie chart.

Solution:

The required pie chart for the given data is:

Scatter Plot

A scatter plot is a type of graphical representation that displays individual data points on a two-dimensional coordinate system. Each point on the plot represents the values of two variables, allowing us to observe any patterns, trends, or relationships between them. Typically, one variable is plotted on the horizontal axis (x-axis), and the other variable is plotted on the vertical axis (y-axis).

Scatter plots are commonly used in data analysis to visually explore the relationship between variables and to identify any correlations or outliers present in the data.

A line drawn in a scatter plot that is near to almost all the points in the plot is called the “line of best fit” or "trend line". The example for the same is added in the image below:

Solved Examples on Data Handling

Example 1: In a survey conducted over a week, from Monday to Sunday, for two cities, Agra and Delhi, the temperatures of both cities were measured, and the obtained temperatures are represented as numbers.

Draw the Bar Graph for the given table in the question.

Solution:

The given table has two categories of data: one for the temperature in Agra and the other for the temperature in Delhi. Therefore, the graph can be drawn as a double-bar graph, which would look like the following

Example 2: In a theater, there are 3 plays with a different number of actors participating in each play. In Play 1, there are 9 actors; in Play 2, there are 3 fewer actors, and the number of actors in Play 3 is one less than in Play 1. Draw the pictograph for the information given and analyze at which point the stage will be most crowded..

Solution:

From the information given in the question, we can say that Play 1 has 9 actors, Play 2 has 6 actors, and Play 3 has 10 actors. Representing the actors in pictorial form:

Representing the actors in pictorial form as follows:

Therefore, we can conclude that Play 3 has the most crowded stage, as it has 10 actors performing on stage.

Example 3: In a weather report conducted over 5 consecutive weeks, it was noted that not all days were sunny during the spring season. The observation revealed that Week 1 had 4 sunny days, Week 2 had 5 sunny days, Week 3 had only 2 sunny days, Week 4 had sunny days throughout the entire week, and Week 5 had only 3 sunny days.

Pictograph for the number of sunny days in each week:

Solution:

Representing sunny days in pictorial form for better understanding,

Example 4: Calculating the Mode

Problem: Find the mode of the following data set: 7, 8, 7, 9, 10, 7, 8.

Solution:

Note:- If one number appears more frequently than others, it is the mode.

• Count the frequency of each number.
• 7 appears 3 times, 8 appears 2 times, 9 appears 1 time, and 10 appears 1 time.
• The mode is the number that appears most frequently.
• Mode = 7

Example 5: Determining the Range

Problem: Calculate the range of the following set of numbers: 12, 7, 15, 9, 14.

Solution:

• The range is the difference between the highest and lowest numbers.
• Highest number = 15
• Lowest number = 7
• Range = Highest - Lowest = 15 - 7 = 8

Practice Problems on Data Handling

1. Draw a pictograph to represent the number of apples, oranges, and bananas sold in a fruit store: Apples (10), Oranges (15), Bananas (12).
2. Create a vertical bar graph showing the number of books sold in January (100), February (120), March (90), and April (110).
3. Draw a horizontal bar graph to represent the number of cars sold in five months: January (15), February (20), March (10), April (25), May (30).
4. Represent the number of students in three classes (Class A: 20, Class B: 25, Class C: 30) using a double-bar graph.
5. Draw a line graph for the temperature recorded over five days: Monday (22°C), Tuesday (25°C), Wednesday (27°C), Thursday (24°C), Friday (23°C).
6. Create a pie chart showing the distribution of different types of fruits in a basket: Apples (40%), Oranges (25%), Bananas (20%), Grapes (15%).
7. Plot a scatter plot to show the relationship between study hours and exam scores for ten students.
8. Draw a pictograph to represent the number of hours spent on homework by five students: A (4 hours), B (3 hours), C (2 hours), D (5 hours), E (4 hours).
9. Create a vertical bar graph to show the scores of students in a test: Alice (85), Bob (90), Charlie (80), and Diana (95).
10. Draw a horizontal bar graph representing the number of hours worked in a week by different employees: John (40 hours), Mary (35 hours), Alex (45 hours), Sarah (30 hours).

Related Reads:

• Real Life Applications of Data Handling
• Difference Between Mean, Median, and Mode with Examples
• Chance and Probability

Summary

Data handling refers to the systematic process of collecting, recording, and representing data in ways that make it easy to understand and analyze. This involves using various graphical methods such as pictographs, bar graphs, line graphs, pie charts, and scatter plots, all of which help visualize data and identify patterns or trends. Mastery of these data handling techniques is essential for making accurate analyses and informed decisions in both academic and professional contexts.