7. High level of subjectivity
Research findings can never be 100%
representatives of population.
The presence of group level information
is required
9. Elements are chosen from among the whole
population based on purpose of the study
Main objective is that the researcher with
his good decision and appropriate policy
chooses those elements which are meant for
fulfilling the research objective
10. ADVANTAGES
Moderately economic in terms of cost and
time because of small sample size
Closely related to the problem of study
Useful for certain types of forecasting
11. DISADVANTAGES
Useful only when the researcher has the
complete knowledge about the population
More biased
Impurities of the sample cannot be judged
12. SNOWBALL SAMPLING
Non probability sampling technique
Snowball sampling technique works as a
chaining system
14. LINEAR SNOWBALL SAMPLING
Formation of a sample group starts with only
subject and subject provides only one referral.
The referral is recruited into the sample group and
he or she also provides only one new referral.
This pattern is continued until the sample group is
fully formed.
15. EXPONENTIAL NON DISCRIMINATIVE
SAMPLING
The first subject recruited to the sample
group provides multiple referrals.
Each new referral is explored until primary
data from sufficient amount of samples are
collected.
16. EXPONENTIAL DISCRIMINATIVE
SAMPLING
Subjects give multiple referrals, however
only one new subject is recruited among
them
The choice of a new subject is guided by the
aim and objectives of the study
17. ADVANTAGES
Ability to recruit hidden populations.
Possibility to collect primary data in cost
effective manner.
A very little planning is required to staet
primary data collection.
18. DISADVANTAGES
Over sampling of a particular network of
peers can lead to bias.
It is not possible to determine sampling
errors.
There is no guarantee about the
representatives of samples.
Editor's Notes
The researcher is well aware of attributes and characteristics of the population unit.
The sample is selected keeping the problem of study in mind for its purposeful solution.
The results obtained are policy affected and bit biased.
Understanding of the whole group is not very easy.
Statistically the obtained results through this technique are less reliable.
Mostly researchers used this sampling technique where participants are difficult to locate in a general population.
2 imp points to be remember,
To find one or more research participants for research
To take reference of participants to get more sample size in research.
Respondants may be hesitant to provide names of peers and asking them to do so may raise ethical concerns.
It is not possible to determine the actual pattern of distribution.
It is not possible to determine the sampling errors and make statistical interferences from the sample to the population due to the absence of random selection of samples.