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Page 1: Various Sampling Techniques
Page 2: Various Sampling Techniques

Refers to those methods which are used for making judgments and taking actions based on sample(taken from population).POPULATION: The larger group of items having common measurable characteristics.SAMPLE: The limited number of items selected from the larger group which itself represents the whole population.NEED: It saves time , money and energy.

Page 3: Various Sampling Techniques

BASIC SAMPLING DESIGN TYPES

RANDOM/ PROBABILITY SAMPLING: Every unit has equal chance to be selected in sample.

NON RANDOM / NON PROBABILITY SAMPLING: Every unit has no equal chance to be selected in sample.

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METHODS

Page 5: Various Sampling Techniques

Each and every unit in the population has an equal and independent chance of being included in the sample .

The method of selection is specified , objective and replicable.

Types:Simple random sampling with replacementSimple random sampling without

replacement.

SIMPLE RANDOM SAMPLING

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MERITS: DEMERITS:Easy to use. Requires up- to

date & complete list of population.Eliminate personal Time consuming & biasedness. costly in case of scattered

information.

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STRATIFIED RANDOM SAMPLING

It is used when population is heterogeneous in nature .

Techniques of stratification(division into different layers or groups) is used.

Methods of allocation of sample size:Proportional allocation Equal allocation

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MERITS:

It gives more representative sample in case of heterogeneous sample.Improves sampling design & brings administrative convenience.

DEMERITS:

Result will be biased in case of faulty stratification.

Difficult to classify in case of small size of population.

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SYSTEMATIC SAMPLING

In this type of sampling only the first sample unit is selected at random and the remaining units are automatically selected in a definite sequence at equal spacing from one another.

MERITS: DEMERITS:

Easy to operate and checking Complete and accurate list of sample is needed. Save time and labour Relative efficiency depends upon properties of population.

Page 10: Various Sampling Techniques

It is used when area is very big. The area is divided in to small overlapping or neighboring areas called CLUSTER.

CLUSTER SAMPLING

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MERITS :

More economical and easy to operate

DEMERITS:

Less efficient.

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First selecting the clusters and then selecting only some elements of the selected clusters.

MULTI-STAGE SAMPLING

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MERITS:More flexible as compared to other methods of

sampling.Different sampling techniques can be used at

different stages.DEMERITS:Errors are likely to be greater due to variability

of the estimates .

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Based on hand picking of the individual elements.

Selection is done by choice not by chance .MERITS: Useful information can be obtained .DEMERITS:Influenced by personal biasness.

NON- RANDOM /NON –PROBABILITY SAMPLING:

Purposive / judgment sampling

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Consist of simply taking the cases that are available.

MERITS:Convenient to useDEMERITS:Personal biasness.

CONVENIENCE SAMPLING

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Used when population size is large and abundant.Used to improve representativeness of the study.LOGIC:Certain relevant characteristics describe the

dimensions of the whole population.MERITS:Used in surveys particularly in the commercial

world .Used to reduce the cost of surveys.DEMERITS:Biasness is there.

QUOTA SAMPLING

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Special type of non probability sampling where respondents are difficult to identify thus best located through referral network.

MERITS :Reduced sample size and cost .DEMERITS:Biasness is likely to enter.

SNOWBALL (Network or chain) SAMPLING

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SPEEDECONOMYADAPTABILITYSCIENTIFIC APPROACHLEADS TO GOOD RESULTS

ADVANTAGES OF SAMPLING

TECHNIQUES:

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Various sampling techniques adopted for investigation usually offers great advantages as to cost, time & sometime even to quality of results .

Simple random & purposive sampling techniques are mostly used at M.Sc. & PhD level.

Multistage sampling and stratified sampling should be used to get proper representation of population.

CONCLUSION:

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Research Methodology by C.R.KothariResearch Methods by John Adams/Hafiz

T.A.KhanResearch for marketing decision by Paul.

E.Green.Marketing management by Arun Kumar.

REFERENCES:

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POSTIVE CRITISISM AND SUGESTIONS ARE WELCOME