Collection of Secondary Data – Sources & Reliability

Secondary Data = Second-Hand Data! Like buying a used car - cheaper and quicker, but you must check its condition first! 🚗

What is Secondary Data?

[!NOTE] Definition: Data which has already been collected by someone else for some other purpose, and is now being used by the investigator.

Also called: Second-hand data, Finished data.

Example:

• Using Census 2011 data for your research project.
• Using RBI reports to study inflation.
• Using cricket scores from Cricinfo.

Sources of Secondary Data 📚

Sources are broadly classified into two: Published and Unpublished.

1. Published Sources 📖

Data made available to the public.

1. Government Publications:

   • Census of India: Population data.
   • NSSO Reports: Employment, consumption.
   • RBI Bulletins: Banking, inflation, currency.
   • Statistical Abstract of India: General stats.

2. International Publications:

   • UNO, WHO, IMF, World Bank reports.
   • Example: WHO report on Covid-19 cases.

3. Semi-Official Publications:

   • Municipal Corporations (Birth/Death rates).
   • District Boards.

4. Reports of Committees & Commissions:

   • Finance Commission Report.
   • Pay Commission Report.

5. Trade Associations & Chambers of Commerce:

   • FICCI, CII reports on industry trends.
   • Stock Exchange reports (BSE/NSE).

6. Journals & Newspapers:

   • Economic Times, Business Standard.
   • Research journals (EPW).

2. Unpublished Sources 📂

Data collected but not published. Usually for internal use.

• Office Records: Company's past sales records, employee records.
• Research Scholars: Unpublished PhD theses.
• Private Agencies: Data collected by consulting firms (McKinsey, Nielsen) for clients.

Precautions While Using Secondary Data ⚠️

"Secondary data should not be accepted at face value." - Connor.

Before using secondary data, you MUST check:

1. Reliability of Source

• Who collected it?
• Is the agency reputed? (RBI vs Random Blog).
• Is the source biased? (Tobacco company funding cancer research?).

2. Suitability of Purpose

• Why was it collected?
• If the original purpose matches your purpose.
• Example: Data on "Unemployed" may define unemployment differently than you do.

3. Adequacy of Data

• Is the sample size enough?
• Is the area coverage sufficient?
• Example: Data from Mumbai cannot be applied to rural Bihar.

4. Method of Collection

• How was it collected?
• Was it a sample or census? Was the method scientific?

5. Time Period

• Is it outdated?
• Example: Using 2010 mobile usage data for 2024 study is useless.

6. Accuracy

• Check for errors.
• Does the data look consistent?

Primary vs Secondary Data: Comparison ⚔️

Summary

• Secondary Data = Already existing data.
• Sources: Published (Govt, International, Journals) & Unpublished (Office records).
• Crucial: Always verify Reliability, Suitability, and Adequacy.
• Cheaper & Faster than primary data but risky if not checked.

The Bottom Line: Use secondary data whenever possible to save money, but use it with caution! 🕵️‍♂️