Census Sample Investigation

1. CENSUS & SAMPLECENSUS & SAMPLE
INVESTIGATIONINVESTIGATION

2. MEANING OF UNIVERSEMEANING OF UNIVERSE
By Universe we mean all the statisticalthe statistical
units of the statistical area which haveunits of the statistical area which have
some common specialities. The group ofsome common specialities. The group of
all the units of the given problem is calledall the units of the given problem is called
universe.universe.
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3. TYPES OF UNIVERSETYPES OF UNIVERSE
i. FINITE & INFINITE UNIVERSE
ii. REAL & HYPOTHETICAL UNIVERSE
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4. MEANING OF CENSUSMEANING OF CENSUS
ENQUIRYENQUIRY
When every unit of the universe is studied
for collection of data then this kind of
enquiry is called census enquiry.
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5. SUITABILITY OF CENSUSSUITABILITY OF CENSUS
ENQUIRYENQUIRY
i. SCOPE IS LIMITED
ii. UNITS ARE OF VARIOUS QUALITIES
iii. DETAIL STUDY IS REQUIRED
iv. HIGH LEVEL OF ACCURACY IS
REQUIRED
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6. MERITS OF CENSUSMERITS OF CENSUS
ENQUIRYENQUIRY
i. MORE RELIABILITY
ii. DETAILED INFORMATION
iii. SUITABLE WHERE UNITS ARE OF
DIFFERENT QUALITIES
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7. DEMERITS OF CENSUSDEMERITS OF CENSUS
ENQUIRYENQUIRY
i. EXPENSIVE
ii. MORE LABOUR & TIME
iii. UNSUITABLE IF UNIVERSE IS
INFINITE
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8. MEANING OF SAMPLEMEANING OF SAMPLE
ENQUIRYENQUIRY
The enquiry in which some units are
selected from a group on some basis and
then those selected units are studied in
detail is known as sample enquiry.
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9. SUITABILITY OF SAMPLESUITABILITY OF SAMPLE
ENQUIRYENQUIRY
i. WIDE SCOPE & LESS ACCURACY
ii. INFINITE STATISTICAL UNIVERSE
iii. DESTRUCTIVE UNITS
iv. IMPOSSIBILITY OF CENSUS ENQUIRY
v. HOMOGENEITY
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10. MERITS OF SAMPLEMERITS OF SAMPLE
ENQUIRYENQUIRY
i. ECONOMICAL
ii. DETAILED STUDY
iii. RELIABILITY
iv. SUITABILITY
v. MORE SCIENTIFIC
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11. DEMERITS OF SAMPLEDEMERITS OF SAMPLE
ENQUIRYENQUIRY
i. LOW LEVEL OF ACCURACY
ii. HETROGENEOUS DATA
iii. AFFECTED BY BIASED FEELING
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12. ESSENTIALS OF SAMPLINGESSENTIALS OF SAMPLING
i. REPRESENTATIVENESS
ii. INDEPENDENCE
iii. HOMOGENEITY
iv. ADEQUACY
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13. OBJECTIVES OF SAMPLINGOBJECTIVES OF SAMPLING
i. TO RECEIVE INFORMATION OF
UNIVERSE
ii. TO ESTIMATE THE PARAMETERS OF
UNIVERSE
iii. TO CHECK ACCURACY
iv. TO CHECK THE TRUTH OF CENSUS 13

19. SIZE OF SAMPLESIZE OF SAMPLE
 The more is the size – more reliable & represent the
universe; suitable for large universe.
 Small sample – not represent the universe; suitable for
small universe.
 Organisation of large sample is difficult & expensive.
 Size depends upon – nature, size of universe , nature
of units, expected accuracy, etc.
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20. TEST OF RELIABILITY OFTEST OF RELIABILITY OF
SAMPLESAMPLE
Test of reliability of sample can be checked
by two methods:
1.Various samples are collected of the same
size & compared with the result of original one.
(similarity then sample is reliable)
2.The selected sample is divided into two equal
parts & qualities are studied separately.
(qualities are same then sample is reliable
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21. RELIABILITY OF SAMPLERELIABILITY OF SAMPLE
It is generally believed that whatever holds
true for a sample by & large holds true for
the entire universe. This belief is based on
two principles:
1.PRINCIPLE OF INERTIA OF LARGE
NUMBERS
2.PRINCIPLE OF STATISTICAL
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22. 1. PRINCIPLE OF INERTIA OF
LARGE NUMBERS
The principle states that, other thingsThe principle states that, other things
being equal, larger the size of the sample,being equal, larger the size of the sample,
more accurate the results are likely to be.more accurate the results are likely to be.
This is because larger numbers are moreThis is because larger numbers are more
stable than small ones.stable than small ones.
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23. 2. PRINCIPLE OF
STATISTICAL REGULARITY
This principle points out that if a sampleThis principle points out that if a sample
is taken at random from a population, it isis taken at random from a population, it is
likely to possess almost the samelikely to possess almost the same
characteristics as those of the population.characteristics as those of the population.
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24. MERITS OF DELIBERATEMERITS OF DELIBERATE
SAMPLINGSAMPLING
i. SIMPLE
ii. SUITABLE WHERE DATA IS
HOMOGENEOUS
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25. DEMERITS OF DELIBERATEDEMERITS OF DELIBERATE
SAMPLINGSAMPLING
i. SELECTION ENTIRELY DEPENDS UPON
PERSONAL FEELING
ii. INACCURATE RESULTS
iii. SUCCESS OF THIS METHOD DEPENDS
UPON KNOWLEDGE, EXPERIENCE,
HONESTY & RELIABILITY OF
INVESTIGATOR
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26. MERITS OF RANDOMMERITS OF RANDOM
SAMPLINGSAMPLING
i. BIASED FREE METHOD
ii. ECONOMY
iii. REAL REPRESENTATION
iv. MEASUREMENT OF SAMPLING
ERROR
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27. DEMERITS OF RANDOMDEMERITS OF RANDOM
SAMPLINGSAMPLING
i. SMALL SIZE OF SAMPLE
ii. HETROGENEOUS SAMPLE
iii. SIZE OF UNIVERSE IS SMALL
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28. MERITS OF SAMPLINGMERITS OF SAMPLING
i. ECONOMY OF COST
ii. ECONOMY OF TIME
iii. RELIABILITY
iv. MINIMUM ERRORS
v. FOLLOW –UP
vi. INFORMATION IN DEPTH
vii. INDESPENSABILITY
viii. CHECKING CENSUS RESULTS 28

29. DEMERITS OF SAMPLINGDEMERITS OF SAMPLING
i. SERVICES OF EXPERTS ARE
REQUIRED
ii. STUDY OF INDIVIDUAL
CONSTITUENT IS REQUIRED
iii. CAREFUL PROPER PLAN IS
REQUIRED
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