The uploaded PDF contains the complete solution set for the worksheet based on Chapter 2, Collection of Data, from Class 11 Economics. This solutions document provides correct answers along with explanations for multiple-choice questions, assertion–reason questions, short answers, and long descriptive questions. It clearly explains the meaning of data, primary and secondary data, their sources, methods of collection, advantages, limitations, and precautions while using data.
I am writing about this solutions PDF because Chapter 2 is one of the most important chapters in the statistics portion of Economics. Many students understand definitions but struggle to apply them in practical situations. A detailed solution guide helps students check their answers, understand why a particular option is correct, and learn how to write proper exam-oriented answers.
As shown in the uploaded solutions PDF CH-2 Collection of data WS 1 SOL, the answers are arranged section-wise and follow the same pattern as the worksheet, making revision easy and systematic.
Solutions to Multiple-Choice Questions
The PDF provides correct options with clear explanations.
Some important points explained include:
• Increase or decrease in production of wheat is an example of variable
• Data collected from some other agency is called secondary data
• Website is not considered a published source
• Primary data is more reliable than secondary data
• Bias in sampling can arise due to faulty selection, collection, or interpretation
These explanations strengthen conceptual clarity.
Meaning of Primary Data
The solutions define primary data as data collected by the investigator for the first time from the source of origin.
Important features:
• Original and first-hand information
• More reliable
• Collected for a specific purpose
• Time-consuming and costly
Examples such as collecting marks of students through direct interaction are given.
Meaning of Secondary Data
Secondary data refers to data already collected and processed by someone else.
Important features:
• Second-hand information
• Less costly
• Saves time
• May not exactly suit the investigator’s purpose
Examples include census reports and government publications.
Download this CH-2 Collection of data WS 1 SOL PDF File: Click Here
Difference Between Primary and Secondary Data
The PDF clearly compares both types of data.
Primary Data:
• Original
• More reliable
• Expensive
• Time-consuming
Secondary Data:
• Not original
• Less reliable
• Economical
• Time-saving
This comparison is important for exams.
Methods of Collecting Primary Data
The solutions explain that there is no single best method of collecting primary data.
Choice of method depends on:
• Nature of investigation
• Availability of resources
• Area of inquiry
Methods include questionnaires, schedules, personal interviews, and telephone interviews.
Sources of Secondary Data
The PDF lists major sources such as:
• Government publications
• Semi-government publications
• Reports of committees and commissions
• Research institutions
• Trade associations
• International publications
Students are expected to remember these sources.
Precautions While Using Secondary Data
The PDF stresses that secondary data must be used with great care.
Precautions include:
• Checking reliability of source
• Ensuring suitability for purpose
• Verifying definitions and units
• Checking adequacy and accuracy
These points are frequently asked in long-answer questions.
Advantages and Disadvantages of Primary Data
Advantages:
• More reliable
• More authentic
• More valid
Disadvantages:
• Costly
• Time-consuming
• Requires effort
These are explained in detail.
Why This Solutions PDF Is Useful
From my experience, this solutions PDF is extremely helpful because:
• It explains answers clearly
• It saves revision time
• It improves exam-writing skills
• It strengthens conceptual understanding
Students who use this guide regularly perform better.
How to Use This PDF Effectively
• Solve the worksheet yourself first
• Compare with solutions
• Note mistakes
• Revise weak areas
• Practise descriptive answers
