RESEARCH METHOD COHEN ok

164 VALIDITY AND RELIABILITY
operationalization of an unseen, half-guessed-at
construct or phenomenon. The community of
scholars has a role to play here. For a full discussion
of validity see Messick (1993). To conclude this
chapter, we turn briefly to consider validity and
reliability in life history accounts.
Validity and reliability in life histories
Three central issues underpin the quality of data
generated by life history methodology. They are to
do with representativeness, validity and reliability.
Plummer draws attention to a frequent criticism
of life history research, namely that its cases
are atypical rather than representative. To avoid
this charge, he urges intending researchers to,
‘work out and explicitly state the life history’s
relationship to a wider population’ (Plummer
1983) by way of appraising the subject on
a continuum of representativeness and nonrepresentativeness.
Reliability in life history research hinges upon
the identification of sources of bias and the
application of techniques to reduce them. Bias
arises from the informant, the researcher, and the
interactional encounter itself. Box 6.1, adapted
from Plummer (1983), provides a checklist of some
aspects of bias arising from these principal sources.
Several validity checks are available to
intending researchers. Plummer (1983) identifies
the following:
The subject of the life history may present
an autocritique of it, having read the entire
product.
A comparison may be made with similar
written sources by way of identifying points
of major divergence or similarity.
Acomparisonmaybemadewithofficialrecords
by way of imposing accuracy checks on the life
history.
Box 6.1
Principal sources of bias in life history research
Source: Informant
Is misinformation (unintended) given
Has there been evasion
Is there evidence of direct lying and deception
Is a ‘front’ being presented
What may the informant ‘take for granted’ and
hence not reveal
How far is the informant ‘pleasing you’
How much has been forgotten
How much may be self-deception
Source: Researcher
Attitudes of researcher: age, gender, class, race,
religion, politics etc.
Demeanour of researcher: dress, speech, body
language etc.
Personality of researcher: anxiety, need for
approval, hostility, warmth etc.
Scientific role of researcher: theory held (etc.),
researcher expectancy
Source: The interaction
The encounter needs to be examined. Is bias
coming from:
The physical setting – ‘social space’
The prior interaction
Non-verbal communication
Vocal behaviour
Source: adapted from Plummer 1983: Table 5.2, p. 103
Acomparisonmaybemadebyinterviewing
other informants.
Essentially, the validity of any life history lies in
its ability to represent the informant’s subjective
reality, that is to say, his or her definition of the
situation.