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Organizational
Psychology (PSY510)
VU
LESSON
02
METHODOLOGIES
OF DATA COLLECTION
Psychologists
use some of the following
methods for research and
data collection:
Experimental
Method
The
experimental research design is when a
cause-and-effect relationship between an independent
and a
dependent
variable of interest is to be clearly
established, then all other
variable that might contaminate
or
confound
the relationship have been tightly
controlled. In other words, the
possible effects of
other
variables
on the dependent variable have been
accounted for in some
way.
(a)
Independent
Variable
An
independent variable is one that
influences the dependent variable in either a
positive or
negative
way. That is, when the
independent variable is present, the dependent
variable, there is an
increase
or decrease in the dependent variable
also. In other words, the
variance in the dependent
variable
is accounted for by the independent
variable. To establish causal
relationships, the
independent
variable is manipulated.
(b)
Dependent
Variable
The
dependent variable is the variable of primary interest
to the researcher. The researcher's
goal is
to
understand and describe the
depend variable, or to explain its
variability, or predict it. In
other
words,
it is the main variable that lends
itself for investigation as a viable
factor. Through the
analysis
of the dependent variable (i.e., finding
what variables influence it), it is
possible to find
answers
or solutions to the problem. For this purpose, the
researcher will be interested
in
quantifying
and measuring the dependent variable, as
well as the other variables
that influence this
variable.
(c)
Intervening
Variable
An
intervening variable is one that
surfaces between the time the independent
variables start
operating
to influence the dependent variable and the time
their impact is felt on it.
The intervening
variable
surfaces as a function of the independent
variable(s) operating in any situation,
and helps
to
conceptualize and explain the influence of the
independent variable(s) on the dependent
variable.
Control
When
we postulate cause-and-effect relationships
between two variables X and
Y, it is possible that
some
other
factors, say A, might also
influence the dependent variable Y. In such a
case, it will not be
possible to
determine
the extent to which Y occurred only
because of X, since we do not
know how much of the
total
variation
of Y was caused by the presence of the
other factor A. For instance
a Human Resource
Development
manager might arrange for
special training to a set of newly
recruited secretaries in creating
web
pages, to prove to his boss
that such training would
cause them to function more
effectively. However,
some
of the new secretaries might
function more effectively
than others, mainly or partly
because they have
had
previous intermittent experienced with
the web. In this case the manager cannot
prove that the
special
training
alone caused greater
effectiveness, since the previous
intermittent experience of some
secretaries
with
the webs is a contamination factor. If the true effect
of the training on learning is to be assessed,
then
the
learner's previous experience has to be
controlled. This is what be mean when we
say we have to
control
the contamination factors.
Observational
method
It
is possible to gather data
without asking questions of
respondents. People can be
observed in their
natural
work environment or in the lab setting,
and their activities and
behaviours or other items of
interest
can
be noted and
recorded.
Apart
from the activities performed by the
individuals under study, their movements,
work habits, the
statements
made and meetings conducted
by them, their facial
expressions of joy, anger,
and other
emotions,
and body language can be
observed. Other environmental
factors such as layout,
work-flow
patterns,
the closeness of the seating arrangement,
and the like, can also be
noted. This is called
observational
method of collecting data.
Case
design: study of a particular
case
Case
studies involve in-depth contextual
analyses of similar situations in
other organizations, where
the
nature
and definition of the problem
happen to be the same as experienced in
the current situation.
Hypothesis
can be developed in case studies as
well.
3
Organizational
Psychology (PSY510)
VU
Longitudinal
methods
The
researcher might want to study people or
phenomenon at more than one
point in time in order to
answer
the research question. For
instance, the researcher might want to
study employees' behaviour
before
an
after a change in the top management, so
as to know what effects change
accomplished. Here, because
data
are gathered at two
different points in time, the study is
carried longitudinally across a
period of time.
Such
studies are called
longitudinal studies and the
method as longitudinal
methods.
Survey
design; Study of
aggregates
Survey
design may be called the
study of aggregates which
means that the data are
colleted through various
instruments
such as questionnaires, interviews etc.
to gather the information about the
variables.
Cross
sectional methods
A
study can be done in which
data are gathered just
once, perhaps over a period
of days or weeks or
months,
in order to answer a research
question. Such studies are
called one-shot or cross-sectional
studies.
Concepts
of Reliability and Validity
Reliability
The
reliability of a measure indicates the
extent to which it is without bias
(error free) and hence
ensures
consistent
measurement across time and
across the various items in the
instrument. In other words, the
reliability
of a measure is an indication of the
stability and consistency
with which the instrument
measure
the
concept and helps to assess
the "goodness" of a measure
Stability
of Measures
The
ability of a measure to remain the
same over time--despite
uncontrollable testing conditions or
the
state
of the respondents themselves--is indicative of
its stability and low
vulnerability to changes in the
situation.
This attests to its "goodness" because
the concept is stably measured, no
matter when it is done.
Two
tests of stability are
test-retest reliability and
parallel-form reliability.
Test-retest
Reliability
The
reliability coefficient obtained with a
repetition of the same measure on a
second occasion is called
test-
retest
reliability. That is, when a
questionnaire containing some
items that are supposed to
measure a
concept
is administered to a set of respondents
now, and again to the same
respondents, say several
weeks
to
6monts later then the correlation
between the scores obtained at the two
different times from one
and
the
same sets of respondents is
called test-retest coefficient. The
higher it is the better the test--
retest
reliability,
and consequently, the stability of the
measure across time.
Parallel-Form
Reliability
When
responses on two comparable
sets of measures tapping the
same construct are highly
correlated, we
have
parallel-form reliability Both forms
have similar items and the
same response format, the
only changes
being
the wording and the order or
sequence of the questions. What we
try to establish here is the
error
variability
resulting from wording and
ordering of the questions. If two
such comparable forms are
highly
correlated
(say 8 and above), we may be
fairly certain that the
measures are reasonably reliable,
with minimal
error
variance caused by wording,
order, or other factors.
Examples (test-retest, split
half.
Split-Half
Reliability
It
is another measure or reliability which
measure the internal consistency of
measures. The
internal
consistency
of measures is indicative of the homogeneity of the
items in the measure that tap the
construct.
In
other words, the items should
"hang together as a set, " and be
capable of independently measuring
the
same
concept so that the respondents
attach the same overall
meaning to each of the
items.
Split-half
reliability reflects the correlations
between two halves of an instrument.
The estimates would
vary
depending
on how the items in the measure
are split into two
halves. For example, if we
split a question are
into
two parts and administer
them independently, we may be able to
check if the answers to the first
half
are
consistent with those to the
second.
Validity
It
refers to the fact that when we ask a
set of questions (i.e., develop a
measuring instrument) with the
hope
that
we are tapping the concept,
how can be we reasonably
certain that we are indeed
measuring the
concept
we set out to do and not
something else? This can be
determined by applying certain validity
tests.
Several
types of validity tests are
used to test the goodness of
measures and writers use
different terms to
denote
them. However, validity
tests may the grouped under the following
headings:
4
Organizational
Psychology (PSY510)
VU
Content
validity
Content
validity ensures that the
measure includes an adequate
and representative set of
items that tap the
concept.
The more the scale items
represent the domain or universe of the
concept being measured, the
greater
the content validity. To put it
differently, content validity is a
function of how well the
dimensions
and
elements of a concept have
been delineated.
A
panel of judges can attest
to the content validity of the instrument. Kidder
and Judd (1986) cite
the
example
where a test designed to
measure degrees of speech impairment
can be considered as having
validity
if it is so evaluated by a group of expert
judges (i.e., professional
speech therapists).
Predictive/Criterion
validity
It
is established when the measure differentiates
individuals on a criterion it is expected
to predict. This can
be
done by establishing concurrent validity or predictive
validity. Concurrent validity is
established when the
scale
discriminates individuals who
are known to be different;
that is, they should score
differently on the
instrument.
Predictive
validity indicates the ability of the
measuring instrument to differentiate
among individuals
with
reference
to a future criterion. For
example, if an aptitude or ability test
administered to employees at
the
time
of recruitment is to differentiate individuals on the
basis of their future job
performance, then
those
who
score low on the test should be
poor performers and those
with high scores good
performers.
Construct
validity
It
testifies to how well the
results obtained from the
use of the measure fit the
theories around which the
test
is designed. In other words, it
shows relationship of characteristic with
other observable
constructs.
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