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SNOWBALL SAMPLING

PRESENTED BY,

SREESHMA S

M ED FIRST YEAR

ROLL NO 39

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  • SNOWBALL SAMPLING OR CHAIN REFERRAL SAMPLING
  • Non probability(non-random)

sampling method

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TYPES

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TYPE-1

Linear snowball sampling

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TYPE-2

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Exponential non-discriminative snowball sampling

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TYPE-3

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Exponential discriminative snowball sampling

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APPLICATIONS

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APPLICATIONS

  1. Medical practices
  2. Social research
  3. Cases of discord

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EXAMPLES

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  1. No official list of names of the members
  2. Difficulty to locate people
  3. People who are not willing to be identified
  4. Secretiveness about their identity

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ADVANTAGES

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ADVANTAGES

  • Ability to recruit hidden populations
  • Possibility to collect primary data in a cost effective manner
  • Less time consuming method
  • A very little planning is required

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DISADVANTAGES

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DISADVANTAGES

  • Over sampling can lead to bias
  • May raise ethical concerns
  • No guarantee about the samples
  • Absence of random selection of samples

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Thank you…..

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