Sampling...A to Z

1. SAMPLING:
A sample is “a smaller collection of units from a population
used to determinetruths about that population”
Methodof sampling:
Randomsampling – a methodof sampling that uses of random
selection so that all units/ cases in the populationhave an equal
probabilityof being chosen.
Non- Random sampling – does not involve random selection and
methodsare not based on the rationale of probability theory.
Randomsamplingmethod:
• Simple random sampling
• Systematic random sampling
• Stratified random sampling
• Multistage sampling
Non-random Sampling method:
• Convenience sampling
• Judgment sampling
• Quota sampling
• Snowball sampling

2. Randomsamplingmethod:
Simplerandom sampling:
A samplingprocedure in which every element in the populationhas
a known and equal chance of being selected as a subject (e.g., drawing
names out of a hat).
Example:
Stratifiedsampling:
Populationis dividedon the basis of characteristic of interest in the
populatione.g. male and female may have different consumption
patterns.
Example:

3. Systematicsampling:
If a sample size of n is desired from a populationcontaining N
elements, we might sample one element for every n/N element in the
population.
Example:
Multi-stage sampling:
The MultistageSampling is the probabilitysampling technique
wherein the sampling is carried out in several stages such that the sample
size gets reduced at each stage.
Example:

4. Non-random Sampling method:
Judgmentsampling:
Judgmental sampling is a non-probability sampling
technique where the researcher selects units to be sampled based on
their knowledge and professionaljudgment.
Example:
Quotasampling:
A quota sample is a type of non-probability sample in which the
researcher selects people according to some fixed standard. That is,
units are selected into a sample on the basis of pre-specified
characteristics so that the total sample has the same distribution
of characteristics assumed to exist in the population being studied.

5. Example:
Conveniencesampling:
A convenience sample is one of the main types of non-probability
sampling methods.A convenience sample is made up of people who are
easy to reach.
Example:

6. Snowballsampling:
Snowball sampling is a non-probabilitysamplingtechnique that is used by
researchers to identify potentialsubjects in studies where subjects are hard
to locate.
Example: