Collection of Data
Class 11 Economics · Statistics for Economics · Chapter 2
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Economics
2~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
All 2 books, one purchase- Economics
Physics, Chemistry, Maths + English
7~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Every subject, one purchase- Mathematics
- Physics
- + 3 more
Physics, Chemistry, Biology + English
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Every subject, one purchase- Physics
- Chemistry
- + 3 more
Accountancy, Business Studies, Economics + English
7~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Every subject, one purchase- Accountancy
- Business Studies
- + 3 more
Economics
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Economics
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Accountancy
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
All 2 books, one purchase- Accountancy
Hindi Elective
2~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
All 2 books, one purchase- हिंदी
Hindi Core
2~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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Chemistry
2~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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Political Science
2~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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Urdu Elective
2~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
All 2 books, one purchase- اردو
- Urdu Elective
Hindustani Music (Vocal / Melodic)
2~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
All 2 books, one purchase- हिंदुस्तानी संगीत
Home Science
2~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
All 2 books, one purchase- Home Science
English Core
2~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
All 2 books, one purchase- Hornbill
- Snapshots
Geography
3~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
All 3 books, one purchase- Geography
Sociology
2~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
All 2 books, one purchase- Sociology
Physics
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
All 2 books, one purchase- Physics
Mathematics
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
TrendingRevise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Physics
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Physics
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Chemistry
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Chemistry
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Biology
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Accountancy
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
TrendingRevise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Accountancy
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Business Studies
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
History
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Geography
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Geography
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Geography
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Political Science
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Political Science
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Sociology
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Sociology
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Psychology
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
English Core · Hornbill
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
English Core · Snapshots
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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- Charts from the book's own data
- Traps corrected
English Elective · Woven Words
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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- Traps corrected
हिंदी (आधार)
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
हिंदी (आधार)
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
हिंदी (ऐच्छिक)
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
हिंदी (ऐच्छिक)
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
संस्कृतम् (केन्द्रिकम्)
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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संस्कृत (ऐच्छिक)
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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- Charts from the book's own data
- Traps corrected
اردو (کور)
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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- Charts from the book's own data
- Traps corrected
اردو (اختیاری)
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Urdu Elective
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Computer Science
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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- Charts from the book's own data
- Traps corrected
Informatics Practices
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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- Charts from the book's own data
- Traps corrected
Home Science
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Home Science
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
Revise all of it in about an hour- Space weighted by unit marks
- Charts from the book's own data
- Traps corrected
Fine Art · Painting
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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Biotechnology
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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Knowledge Traditions
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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सृजनात्मक लेखन और अनुवाद
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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Health and Physical Education
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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हिंदुस्तानी संगीत (गायन / वादन)
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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- Charts from the book's own data
- Traps corrected
हिंदुस्तानी संगीत (गायन / वादन)
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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- Charts from the book's own data
- Traps corrected
हिंदुस्तानी संगीत (तबला / पखावज)
~140days leftAnnual exams · school dates varyFeb–Mar 2027 · school-specific · tentative
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- Charts from the book's own data
- Traps corrected
Summary
After knowing why data matter, the next step is to collect them, since data help understand a problem by providing evidence. A quantity that varies, like food-grain output across years, is a variable (denoted X, Y or Z), and each value is an observation. Data come from two sources: primary data are gathered first-hand through an enquiry, while secondary data have already been collected and processed by another agency and reused from reports, books, newspapers or websites; the same figures are primary to the body that first compiles them and secondary to all who borrow them later. A survey gathers information through a questionnaire whose questions should be short, clear and unambiguous, avoid double negatives and leading phrasing, and move from general to specific. Data can be collected by personal interview, mailed questionnaire or telephone interview, differing in cost, response rate and reach; a pilot survey pre-tests the questionnaire first. A survey may cover every unit (a census or complete enumeration, done in India every ten years) or only a representative sample, which is cheaper. Samples are chosen by random methods, where every unit has an equal chance, or non-random methods relying on judgement. Errors are of two kinds: sampling errors, the gap between a sample estimate and the true value, which shrink with larger samples, and non-sampling errors from bias, non-response or faulty recording. The Census of India and the National Sample Survey are key agencies.
Collection of Data
Key terms
Primary data
Data collected first-hand by the investigator through an original enquiry or survey.
Secondary data
Data already collected and processed by another agency and reused by the investigator.
Census
A survey that covers every unit of the population; complete enumeration, done in India every ten years.
Sample
A representative section of the population from which information is gathered at lower cost and time.
Sampling error
The difference between a sample estimate and the corresponding true population value.
Pilot survey
A small try-out of the questionnaire before the main survey, to pre-test it for shortcomings.
Extra questions & answers
Try one from this chapter
Data collected first-hand by the investigator are called: