What is Sample in research and its selection criteria in qualitative and quantitative research

1.  Sumbul Fatima
 B.Ed(Hons)
 UNIVERSITY OF EDUCATION

2. According Webster(1985), research is to
search or investigate exhaustively. It is
a careful or diligent search, studious
inquiry or examination especially
investigation or experimentation
aimed at the discovery and
interpretation of facts,

3. Revision of accepted theories or laws in
the light of new facts or practical
application of such new or revised
theories or laws, it can also be the
collection of information about a
particular subject.

5.  A sample is a finite part of a statistical
population whose properties are
studied to gain information about the
whole(Webster,1985) When dealing
with people.
 It can be defined as a set of
respondents(people) selected from a
larger population for the purpose of a
survey.

9.  To draw conclusions about populations
from samples
 We must use inferential statistics which
enables us to determine a population`s
characteristics by directly observing only
a portion (or sample) of the population
 It is cheaper to observe a part rather
than the whole

10.  Quantitative research is the collection
and analysis of numerical data to
describe, explain, predict, or control
phenomena of interest
 A quantitative research approach
entails more than just the use of
numerical data

11.  At the outset of a study, quantitative
researchers state the hypotheses to be
examined and specify the research
procedures that will be used to carry out
the study.
 Many quantitative researchers have little
personal interaction with the participants
they study because they frequently
collect data using paper-and-pencil,
non-interactive instruments.

13.  Quantitative researchers generally do not
gather data from the entire population—
it’s rarely necessary and even more
rarely feasible, especially if the
population of interest is large or
geographically scattered
 If a sample is well selected, the results of
a study testing that sample should be
generalizable to the population.

14.  That is, the results of the research will be
applicable to other samples selected
from the same population
 Several relatively simple sampling
techniques can be applied to select what
is known as a representative sample
 These procedures do not guarantee that
the sample will be perfectly
representative of the population, but
they definitely increase the odds

17.  A population is all the individuals or units of
interest; typically, there is not
 available data for almost all individuals in a
population.
 The first step in sampling is to define the
population to which results will be
generalizable.


18.  all 10th-grade students in the United States
 all gifted elementary school children in Utah
 all first-grade students in Utopia County who
have physical disabilities and have
participated in preschool training

19.  These examples illustrate two important
points about populations.
 First, populations may be any size and may
cover almost any geographical area. Second,
the entire group of interest to the researcher
is rarely available

20.  Random sampling
Simple random sampling
Stratified sampling
Cluster sampling
Systematic sampling
 Non random sampling
Convenience sampling
Purposive sampling
Quota sampling

21. In quantitative research, a good sample is one that is
representative of the population from which it was
selected, and selecting a representative sample is
not a haphazard process.
A random sample is a subset of individuals that are
unsystematically selected from a population of
interest. Random sampling are also known as
probability sampling

22. There are four basic techniques or procedures
for selecting a random sample.
Simple random sampling
 stratified sampling
Cluster sampling
Systematic sampling

23. Simple random sampling is the process of selecting
a sample in such a way that all individuals in the
defined population have an equal and independent
chance of selection for the sample. Random
sampling is the best way to obtain a representative
sample.

24.  Identify and define population
 Determine the desired sample size
 List all members of population
 Assign all individuals on the list a consecutive
number from zero to the required number.
 Select an arbitrary number in the table of
random numbers.

25. Stratified sampling is a way to guarantee
desired representation of relevant subgroups
within the sample. In other words some
population can be subdivided into subgroups.
Stratified sampling involves strategically
selecting participants from each subgroup.

26.  Identify and define population
 Determine desired sample size
 Identify the variable and subgroups
 Classify all members of population as
members of one of the identified
subgroups.
 Randomly select an equal number of
individuals from each subgrouo.

27. Cluster sampling intact groups not individuals, are
randomly selected. Any location within which we
find an intact groups of population member with
similar characteristics is a cluster.

28.  Identify and define population
 Determine the desired sample size
 Identify and define a logical cluster
 List all cluster that make up the population
of clusters
 Estimate the average number of population
 Include in your study all population members
in each selected cluster.

29. Systematic sampling is sampling in whichever kth
individual is selected from a list. The list includes all
the individuals in the population, and k is a variable
determined by dividing the number of individuals on
the list by the number of subjects desired for the
sample.

30.  Identifying and define population
 Determine the desired sample size
 Obtain a list of population
 Start at some random place in the population
list. Close your eyes and stick your finger on
a name.
 Starting at that point, take every kth name
on the list until the desired sample size is
reached.

31. Non random sampling is the process of
selecting a sample using a technique that does
not permit the researcher to specify the
probability, or chance that each member of a
population has of being selected for sample.
Non random sampling includes:
Convenience sampling
Purposive sampling
Quota sampling

32. Convenience sampling also referred to as
accidental sampling or haphazard sampling,
is the process of including whoever happens
to be available at the time

33. Purposive sampling also referred to as
judgment sampling, is the process of
selecting a sample that is believed to be
representative of a given population, or
researcher selects the sample using his
experience and knowledge of the group to be
sampled.

34. Quota sampling is the process of selecting a
sample based on required, exact numbers or
quotas of individuals or groups with varying
characteristics.

36.  Qualitative Research is primarily exploratory
research. It is used to gain an understanding
of underlying reasons, opinions, and
motivations. It provides insights into the
problem or helps to develop ideas or
hypotheses for potential quantitative
research.
 In simple words it is consisting on its two
participants which are characteristics and
knowledge of the required area.

38.  A research participant, also called a human
subject or an experiment, trial, or study
participant or subject, is a person who
participates in human subject research by
being the target of observation by
researchers.

39.  Qualitative research most often deals with
small, purposive samples. The researchers
insights, gained through first-hand
experience in the research setting, guide the
selection of participants.
 Purposive sampling approaches include
intensity sampling, homogeneous sampling,
criterion sampling, snowball sampling and
random purposive sampling.

41.  Criterion sampling involves selecting cases
that meet some predetermined criterion of
importance (Patton, 2001, p. 238). For
example: ... Criterion sampling can be useful
for identifying and understanding cases that
are information rich.

43.  Purposive sampling, also known as
judgmental, selective or subjective sampling,
is a type of non-probability sampling
technique.

45.  There are no hard and fast numbers that
represent the correct numbers of participants
in a qualitative study. Qualitative studies can
be carried out with a single participant or,
when studying multiple contexts, may have
as many as 60 or 70 participants.
 Two general indicators used to determine
whether a sample is of sufficient as
representativeness and redundancy of
information.