RESEARCH METHOD COHEN ok

142 VALIDITY AND RELIABILITY
social sciences have been put. One writer, for
example, comments:
Much research has employed particular methods or
techniques out of methodological parochialism or
ethnocentrism. Methodologists often push particular
pet methods either because those are the only ones
they have familiarity with, or because they believe
their method is superior to all others.
(Smith 1975)
The use of triangular techniques, it is argued,
will help to overcome the problem of ‘methodboundedness’,
as it has been termed; indeed
Gorard and Taylor (2004) demonstrate the
value of combining qualitative and quantitative
methods.
In its use of multiple methods, triangulation may
utilize either normative or interpretive techniques;
or it may draw on methods from both these
approaches and use them in combination.
Referring us back to naturalistic inquiry, Lincoln
and Guba (1985: 315) suggest that triangulation is
intended as a check on data, while member checking,
and elements of credibility, are to be used as a
check on members’ constructions of data.
Types of triangulation and their
characteristics
We have just seen how triangulation is
characterized by a multi-method approach to
a problem in contrast to a single-method
approach. Denzin (1970b) has, however, extended
this view of triangulation to take in several other
types as well as the multi-method kind which he
terms ‘methodological triangulation’:
Time triangulation: this type attempts to take
into consideration the factors of change
and process by utilizing cross-sectional and
longitudinal designs. Kirk and Miller (1986)
suggest that diachronic reliability seeks stability
of observations over time, while synchronic
reliability seeks similarity of data gathered in
the same time.
Space triangulation: this type attempts to overcome
the parochialism of studies conducted in
the same country or within the same subculture
by making use of cross-cultural techniques.
Combined levels of triangulation: this type uses
more than one level of analysis from the three
principal levels used in the social sciences,
namely, the individual level, the interactive
level (groups), and the level of collectivities
(organizational, cultural or societal).
Theoretical triangulation: this type draws upon
alternative or competing theories in preference
to utilizing one viewpoint only.
Investigator triangulation: this type engages
more than one observer, data are discovered
independently by more than one observer
(Silverman 1993: 99).
Methodological triangulation: this type uses
either the same method on different occasions,
or different methods on the same object of
study.
Many studies in the social sciences are
conducted at one point only in time, thereby
ignoring the effects of social change and
process. Time triangulation goes some way to
rectifying these omissions by making use of crosssectional
and longitudinal approaches. Crosssectional
studies collect data at one point in
time; longitudinal studies collect data from the
same group at different points in the time
sequence. The use of panel studies and trend
studies may also be mentioned in this connection.
The former compare the same measurements
for the same individuals in a sample at several
different points in time; and the latter examine
selected processes continually over time. The
weaknesses of each of these methods can be
strengthened by using a combined approach to
a given problem.
Space triangulation attempts to overcome the
limitations of studies conducted within one
culture or subculture. As Smith (1975) says,
‘Not only are the behavioural sciences culturebound,
they are sub-culture-bound. Yet many
such scholarly works are written as if basic
principles have been discovered which would
hold true as tendencies in any society, anywhere,
anytime’. Cross-cultural studies may involve the