RESEARCH METHOD COHEN ok

ALLOTTING ELEMENTS TO CONSTRUCTS 437
would be strengthened by the additional statement
that ‘persons resemble each other in their
construction of events’.
Can the practice of providing constructs to
subjects be reconciled with the individuality
corollary assumptions A review of a substantial
body of research suggests a qualified ‘yes’:
[While] it seems clear in the light of research
that individuals prefer to use their own elicited
constructs rather than provided dimensions to
describe themselves and others ... the results of
several studies suggest that normal subjects, at
least, exhibit approximately the same degree of
differentiation in using carefully selected supplied
lists of adjectives as when they employ their own
elicited personal constructs.
(Adams-Webber l970)
However, see Fransella and Bannister (1977) on
elicited versus supplied constructs as a ‘gridgenerated’
problem.
Bannister and Mair (1968) support the use
of supplied constructs in experiments where
hypotheses have been formulated and in those
involving group comparisons. The use of elicited
constructs alongside supplied ones can serve
as a useful check on the meaningfulness of
those that are provided, substantially lower
inter-correlations between elicited and supplied
constructs suggesting, perhaps, the lack of
relevance of those provided by the researcher. The
danger with supplied constructs, Bannister and
Mair (1968) argue, is that researchers may assume
that the polar adjectives or phrases they provide
are the verbal equivalents of the psychological
dimensions in which they are interested.
Allotting elements to constructs
When a subject is allowed to classify as many or
as few elements at the similarity or the contrast
pole, the result is often a very lopsided construct
with consequent dangers of distortion in the
estimation of construct relationships. Bannister
and Mair (1968) suggest two methods for dealing
with this problem which we illustrate in Box 20.2.
The first, the ‘split-half form’, requires the subject
to place half the elements at the similarity pole
of each construct, by instructing the subject to
decide which element most markedly shows the
characteristics specified by each of the constructs.
Those elements that are left are allocated to
the contrast pole. As Bannister (1970) observes,
this technique may result in the discarding of
constructs (for example, male–female) which
cannot be summarily allocated. A second method,
the ‘rank order form’, as its name suggests,
requires the subject to rank the elements from
the one which most markedly exhibits the
particular characteristic (shown by the similarity
pole description) to the one which least exhibits
it. As the second example in Box 20.2 shows,
a rank order correlation coefficient can be
used to estimate the extent to which there is
similarity in the allotment of elements on any
two constructs. Following Bannister (1970), a
‘construct relationship’ score can be calculated
by squaring the correlation coefficient and
multiplying by 100. (Because correlations are not
linearly related they cannot be used as scores.)
The construct relationship score gives an estimate
of the percentage variance that the two constructs
share in common in terms of the rankings on the
two grids.
Athirdmethodofallottingelementsisthe
‘rating form’. Here, the subject is required to judge
each element on a 7-point or a 5-point scale,
for example, absolutely beautiful (7) to absolutely
ugly (1). Commenting on the advantages of the
rating form, Bannister and Mair (1968) note that it
offers the subject greater latitude in distinguishing
between elements than that provided for in the
original form proposed by Kelly. At the same time
the degree of differentiation asked of the subject
may not be as great as that demanded in the
ranking method. As with the rank order method,
the rating form approach also allows the use of
most correlation techniques. The rating form is
the third example illustrated in Box 20.2.
Alban-Metcalf (1997: 317) suggests that there
are two principles that govern the selection of
elements in the repertory grid technique. The
first is that the elements must be relevant to
that part of the construct system that is being
Chapter 20