quota sampling

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A PRESENTATION ON “QUOTA SAMPLING” Presented By: (ARYAN’S) Abishek Kumar Ajit Kumar Gaganjit singh Praveen Kumar

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Page 1: Quota Sampling

A PRESENTATION ON “QUOTA SAMPLING”

Presented By: (ARYAN’S) Abishek Kumar Ajit Kumar Gaganjit singh Praveen Kumar Sumanto Sharan Swapnil Adahalli

Page 2: Quota Sampling

SAMPLING Sampling may be defined as the selection of some part of an aggregate or totality on the basis of which a judgement or inference about the aggregate or totality is made.

It is the process of obtaining information about an entire population by examining only a part of it.

The process of selecting sample from the population is called sampling.

Page 3: Quota Sampling

WHY SAMPLE ?

Saves moneySaves timeA sample can be more accurate; it has fewer “nonsampling” errors than a census.

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TYPES OF SAMPLING

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PROBABILITY SAMPLING

Simple random sampling Systematic random sampling Stratified sampling Cluster sampling Multi-stage sampling

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NON-PROBABILITY SAMPLING

Deliberate sampling Quota sampling Sequential sampling Snowball sampling Panel sampling Shopping mall sampling

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QUOTA SAMPLING

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In quota sampling the selection of the sample is made by the interviewer, who has been given quotas to fill from specified sub-groups of the population.

For example, an interviewer may be told to sample 50 females between the age of 45 and 60.

QUOTA SAMPLING

Page 9: Quota Sampling

In quota sampling the selection of the sample is non-random.

For example interviewers might be tempted to interview those who look most helpful. The problem is that these samples may be biased because not everyone gets a chance of selection. This random element is its greatest weakness and quota versus probability has been a matter of controversy for many years

CONT…..

Page 10: Quota Sampling

Pre-plan number of subjects in specified categories (e.g. 100 men, 100 women) In uncontrolled quota sampling, the subjects chosen for those categories are a convenience sample, selected any way the interviewer chooses

In controlled quota sampling, restrictions are imposed to limit interviewer’s choice No call-backs or other features to eliminate convenience factors in sample selection

QUOTA SAMPLING…..

Page 11: Quota Sampling

Quota Sampling Most commonly used non-probability method Select a sample on specified criteria (usually to make similar to target population)

Pick people to fill quota on characteristics especially important to research goals

Example: Studying political issues, set quota on party identification

Sample of 200 Registered Republicans 50% Sampled Republicans 100 Registered Democrats 40% SampledDemocrats 80 Registered Independents 10% SampledIndependents 20

Using quotas for several criteria

Race/Ethnicity Black White Latino/a Asian Gender Gender Gender Gender

Political M F M F M F M F Affiliation Democratic Republican Independent

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Quick and cheap to organise

Advantages

Not as representative of the population as a whole as other sampling methods Because the sample is non-random it is impossible to assess the possible sampling error

Disadvantages

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Quota Vs Stratified Sampling

QUOTA SAMPLING STRATIFIED SAMPLING

In Quota Sampling, interviewer selects first available subject who

meets criteria: is a convenience sample.

In Stratified Sampling, selection of subject is

random. Call-backs are used to get that particular

subject

Highly controlled quota sampling uses probability sampling down to the last

block or telephone exchange

Stratified sampling without call-backs may

not, in practice, be much different from quota

sampling.

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THANK YOU