CHAPTER: TWO
FUNDAMENTAL
CONCEPT ON RESEARCH
2.1 Hypothesis
2.2 Sampling, it’s characteristics,
types, benefits and problems
2.3 Field work
2.4 Validity
2.5 Reliability
2.1-Hypothesis
Hypothesis
is a tentative assumption made in order to draw out and test its logical or
empirical consequences.
To
clarify the concept of hypothesis, some definitions are considered,
According
to,
Black and champion:
Hypothesis is a tentative statement of something, the valid of which is usually
unknown.
Bailey: Hypothesis
is a proposition that is stated in a testable forms and that predicts a
particular relationship between two or more variables. In other words if we
think that the relationship exist, we first state if as a hypothesis and then
test the hypothesis in the field.
A
hypothesis is thus a statement about the relationship between two or more
variables which needs to be investigated for its truth. It is basically a
working assumption.
Characteristics/Attributes/Qualities of good Hypothesis
We know that a hypothesis is a proposed explanation for a particular
phenomenon. It is usually considered the principal instrument in research. The
result of hypothesis are not certain and hundred percent true. A good
hypothesis possesses the following certain attributes.
1. A hypothesis should
be simple specific and conceptually clear, i.e. there is no place for ambiguity
in the construction of hypothesis as ambiguity will make the verification of
hypothesis almost impossible.
For example: The
average age of male students in the class is higher than that of female.
2. A hypothesis should
be capable of verification, i.e. methods and techniques most be available for data
collection and analysis. There is no point in formulating a hypothesis if it
cannot subjected to verification.
However this does not necessary mean that we should not formulate a hypothesis
for which there are no methods of verifications during our research work.
3. A hypothesis should
be operationaizable,
i.e. it can be expressed in terms of something that can be measured. If it
cannot be measured, it cannot be tested and no conclusions can be drawn.
4. Hypothesis should
be focused on a specific problem.
5. Hypothesis should
state the condition and circumstances under which it is suppose to apply. The
context and study units must be cleared.
Functions of hypothesis:
Hypothesis
are inevitable in scientific research. They have the following function to
perform.
1. The formulation of
hypothesis provides study with focus. It tells us what specific aspects of
research problem to investigate.
2. A hypothesis tells
us what data to collect and what not to collect.
3. As hypothesis
provides a focus, the construction of hypothesis enhances objectivity in the
study
4. A hypothesis may
enable us to add to the formulation of theory. It enable us to conclude what is true and what is false.
Testing of Hypothesis:
Testing
of hypothesis consists of three phases:
a)
Construction of hypothesis.
b)
Collecting data and evidences.
c)
Analysis data and evidences to draw conclusion.
Sources of hypothesis A
hypothesis may be formulated through a number of sources. Following are the
main sources of hypothesis. 1. -Previous study 2. -Personal experience 3. -Imagination and
thinking 4. -Observation 5. -Scientific theory 6. -General culture
2.2-Sampling Sample:
Sample
is the collection of units which has been specially selected to represent a
large population with certain attributes of interest. Which
population the sample should be? How
large the sample should be. What
is mean by specially selected.
Population:
Population
is the collection of specified group of human being or non-human identities
such as objects, educational institution, geographical areas. Population may be
finite or infinite. This group usually has some common characteristics that
define it. In sampling theory population means the large group from which the
sample are taken to draw conclusion. A parameter is a measure that describe the
whole population.
Census:
The
measurement of examination of every element in population is census. Census gives
more reliable data when, -The
population is very large. -Quick
results are required. -In
minimizing the cost and time of inquiry. -When
the population is hypothetical.
Sampling:
Sampling
may be define as the selection of part of population on the basis of which
judgement or inferences about the universes made.
Types of sampling: Sampling
methods
There
are many sampling techniques that can be used depending on the research
question, the population of interest and other factors. 1. Random / probability sampling a.) Simple Random Sampling -Simplest
method and forms the basis of all other methods. -The
units are selected in such a way that each and every units of population has a
equal chance of being selected. -The
selection of an item depends on chance and not on judgement of the
investigator. Therefore this method is also known as method of chance
selection. Merits: -It
is free from personal biased of the investigator. -Relatively
cheap and simple and can be easily performed in short period of time. Demerits: -Can
be used when we have complete list of population, such list always not
available. -Becomes
costly and time consuming when the field of inquiry is very large and scattered. -Results
will be miss leading if the size of sample is not sufficiently large.
b.) Stratified Random Sampling -In
simple random sampling, the population to be sampled is treated as homogenous
and individual elements are drawn at random from the universe. But if the
population is heterogenous with respect to variable or characteristics under
consideration, stratified random sampling is generally applied in order to
obtain representative sample. -The
population is divided into various homogenous groups or strata on the basis of
certain characteristics so that various strata are non-overlapping. Then a
simple random sampling is used to select a sample from each strata. These
samples are then combined to form a single sample of the universe. -The
procedure where we have stratification first and then random sampling technique
is known as stratified random sampling. Merits: -The
investigator first uses his/her judgement to divide the population into various
strata. The selection is then done by random sampling technique. So this method
enjoys that benefit of both the judgement method and simple random method. -In
many field of highly skewed distribution, stratification is very effective and
valuable too -As
different strata are taken into account, each group of the population will be
adequately represented in the sample. Demerits:
-Results
will not be reliable if each stratum does not contain homogenous unit. -Will
not be effective if different strata are overlapping . -Does
not help when data are needed about options with a low probability of choice in
population.
c.) Systematic Random Sampling -Such
method of sampling in which the first sample unit is selected at random and the
remaining units are automatically selected at fixed equal interval from one
another. -Successfully
used when the complete and upto date information of sampling units is
available. Merits:
-The
method is very simple and convenient. -Saves
time, money, and efforts. -More
efficient than simple random sampling if the list of is complete and unit are
serially arranged at random. Demerits: -If
the list of units is not arranged in random order result may be misleading. -In
some cases the sample will not represented the universe.
d.)
Clustered Sampling -Methods
of random sampling in which the population is divided into groups called
cluster in such a way that characteristics with in the cluster are heterogenous
and between the cluster are homogenous, so that the number of sampling units in
each cluster should be approximately same and then a simple random sampling
technique is applied. These individual cluster are the representative of
population as a whole. -The
difference stratified random sampling and cluster random sampling is that
stratified random sampling is used when each group has same variation within
itself but there is wide variation between the groups whereas the cluster
sampling is used when there is considerable variation with each group but the
groups are essentially similar to each other. Merits: -Elements
selected by well designed cluster sampling procedure is easier, faster,
cheaper, and more convenient than simple random sampling and stratified random
sampling. -Used
when the population under study is infinite, where a list of units of population
does not exist, when the geographical distribution of units is scattered or
when sampling of individual units is not convenient for several administrative
regions. Demerits: -Sampling
efficiency of cluster sampling methods is likely to decrease with increase in
cluster size. -Not
to be recommended for taking samples from private residential homes, business
and industrial complexes due to widely varying number of persons are
households.
Stratified Random Sampling Cluster Sampling
e.)
Multistage Sampling -It is the development of cluster
sampling. -It is a case of random sampling but
sampling is done in various stages. -At first stage universe is divided
into large sampling unit and sample is selected at random from them. -At second stage the sample selected at
first stage are divided into smaller sampling units again from which a further
random sample is taken. -Sampling in any other stages may be
done in same way till we get the required result. Merits: -Quite
convenient when the area of investigation is large. -As
the sample size is reduced at each stage, this method saves time and cost. Demerits: -Generally
less accurate other sample of same size which has been selected by a suitable
single stage method. 2. Non-Random / Non-Probability
Sampling a.)
Judgment/purposive/Deliberate Sampling -Samples
are taken at the judgement of researcher as that fulfils his/her purpose. -It
refers to the sample selected on the basis of what some experts thinks.
b.)
Convenience Sampling -In
this method selection of sample depends of the convenience of researcher. -The
sample then would not necessarily be representative.
c.)
Quota Sampling -Derives
its name from the practice of assigning proportion of kind of people to
interview. -Some
Quota are divided to each grow and then samples are selected. -Chances
of biasness exist.
d.)
Snowball Sampling -Snowball
sampling is a non-probability sampling method where new units are selected by
other units to form the part of sample. -Also
known as chain sampling or network sampling. Snowball sampling begin with one
or more study participants, it then continuous on the basis of retrials from
those participants. This process continues until the desire sample is achieved. -It
is the useful way to conduct research about people with specific
characteristics who might otherwise be difficult to identify. E.g. A person with a rare disease.
Advantages of Sampling -Save
time and resources. -In-depth
study can be carried out. -Easy
to work in limited scope. -Limited
number of surveyor are used, there it is easy to provide direction to the
surveyor.
Disadvantage of Sampling -Difficult
to define sample size and characteristics. -Does
not gives good result it sample is biased. -Difficult
to judge, the sample and good representation of population or not. -Sometime
it is difficult to rely on sample and difficult to convenience people about
finding and validity of research.
Sampling Error -Sampling
survey involves the study of small portion of population and drawing insure
about the population and such there will be on insecurely or errors. Such
errors are known as sampling errors. -Those
errors which arise due to the use of sample survey due to chance are sampling
error. If the censes is taken, sampling error could be expected disappear. The
magnitude of sampling error depends upon the nature of the population and the
size of same. Sampling error is inversely proportional to the size of sample.
Non-Sampling Error -That
portions of difference that can be specifically assign to carelessness in the
design of sampling scheme on in planning and of survey, on in collection,
processing and analysis of data. -Non-sampling
error occurs in all survey, whether it be census or a sample. -Larger
the size of sample, larger will be the non-sampling error.
Sampling Biased -Sampling
biased is caused by mistake made when defining population. -Sampling
biased differ from the sampling. -Sampling
biased effect not only the variability under the mean of the estimated
parameter but the value themselves, thus has more sever distortion of the
surveyor result.
Type
1 Error It
is the rejection of null hypothesis when it is true.
Type
2 Error It
is the acceptance of null hypothesis when it is false.
2.3-Field
Work Organized,
systematic, data based scientific investigation in specific situation under
taken with the objective of gathering information that enables one to gained
familiarity with the situation and generate more knowledge about phenomena
under investigation. Key points to be considered during
field work 1.) Selection of field -Field
area should be identified clearly. -It
should be relevant to topic. àIt
should be easy geographically, socially and environmentally. 2.)
Preparation for field work a.)
Preparation of individual surveyor -Surveyor
should be mentally and physically prepare. -Should
be clear about study and scope. -Should
be compatible to work in adverse situation. -Should
be expert in his/her field. b.)
Preparation of equipment that may include stationary material, maps, camera,
clothes, food and medicine c.)
Preliminary survey -Preliminary
study of concerned literature, inquire with the experts of that field. -Rehearsal
of field study. d.)
Report -The
surveyor should not be biased. -He/she
should talk less and listen more. -He/she
should not be politically influenced. -He/she
shall have a good moral character.
e.)
Use of keys information -Key
information about the society or field of study that may contribute for
reliable data. f.)
Note Taking -All
information should be noted. -The
surveyor group should not be distributed and interrupted during interview.
Activities involved during Field Work 1.)
Pre-Field activities -Selection
of study area that depends upon interest of the surveyor, capability and
fusibility of the study. -Selection
of study skill such as case study or fusibility study. -Selection
of organization. -Preparation
for plane, data collection method and instruments. -Consulting
library for more information. -Taking
feedback and suggestion from the experts.
2.)
Field Work Activities a.)
Initial phase -One
should be introduced him/herself to the
organization. This includes meeting with the stoke holders and collection of
relevant material. b.)
Observation phase -This
is the practical of field work. One should study and observe the action of the
organization. They need to collect relevant data and observe the work system
environment. c.)
Concluding phase -Rapping
of the collected material or observed system.
3.)
Post Field Work Activities Final
stage of field work means one needs to be prepared for report writing. It
includes: -Organizing
data in a meaningful way. -Presenting
observations wherever appropriate. -Writing
the field work report in the recommended format and reporting the field work
report. -Submitting
the report.
2.4-Validity The
concept of appropriateness and accuracy as applied to a research process is
called validity. As inquries can be introduced into a study at any stage, the
concept validity can be applied to the research process as a whole or to any of
its steps. Broadly there are two prospectives on validity: a.)
Is the researcher investigation providing answers to the researcher questions
for which it was undertaken. b.)
If so is it providing these answers using appropriate methods procedures. Validity
refers to the truthfulness of findings. It determines whether the research
truly measured when it was intended to measure or how truthful the research
results are. Validity
is also define as the degree to which the researcher has measure what he/she
has setout to measure.
2.5-Reliability The
extends to which results are consistent over time and then accurate
representation of total population under study is referred to as reliability,
and if the results of the study can be reproduced under a similar methodology,
then the research instrument is consider to be reliable. Relation between Validity and
Reliability 1.)
High reliability but low validity -The
indicators measure something consistently but not the intended concept. 2.)
High validity but low reliability -The
indicators represent the concept but doesn’t produce consistent measurement. 3.)
Low validity but high reliability -It
is the worst case where the indicators neither measure the concept nor produce
consistent result of whatever they measure. 4.)
High validity but low reliability -The
indicators consistently measure what they intend to measure.
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