RESEARCH METHOD COHEN ok

FACTOR ANALYSIS: AN EXAMPLE 571
scored on a continuum ranging from ‘strongly
disagree’ to ‘strongly agree’. A further 38 items
had to do with possible sources of occupational
stress. Here, respondents rated the intensity of
the stress they experienced when exposed to
each source. Stress items were judged on a scale
ranging from ‘no stress’ to ‘extreme stress’. In yet
another section of the questionnaire, respondents
rated how responsible they felt certain nominated
persons or institutions were for the occupational
stress that they, the respondents, experienced.
These entities included self, pupils, superiors,
the Department of Education, the government
and society itself. Finally, the teacher-participants
were asked to complete a 14-item locus of control
scale, giving a measure of internality/externality.
‘Internals’ are people who see outcomes as a
function of what they themselves do; ‘externals’ see
outcomes as a result of forces beyond their control.
The items included in this lengthy questionnaire
arose partly from statements about teacher stress
used in earlier investigations, but mainly as a
result of hunches about blame for occupational
stress that the researchers derived from attribution
theory. As Child (1970) observes:
Box 25.8
Factor analysis of responsibility for stress items
Factor groupings of responsibility items with factor
loadings and (rounded) percentages of teachers
responding in the two most extreme categories of
much stress and extreme stress.
Loading Percentage
Factor 1: School structure
Superiors 0.85 29
School organization 0.78 31
Peers 0.77 13
Factor 2: Bureaucratic
authority
Department of Education 0.89 70
Government 0.88 66
Factor 3: Teacher–student
relationships
Students 0.85 45
Society 0.60 60
Yourself 0.50 20
Source:McCormickandSolman1992
Chapter 25
In most instances, the factor analysis is preceded by a
hunch as to the factors that might emerge. In fact, it
would be difficult to conceive of a manageable analysis
which started in an empty-headed fashion....
Even the ‘let’s see what happens’ approach is pretty
sure to have a hunch at the back of it somewhere. It is
this testing and the generation of hypotheses which
forms the principal concern of most factor analysts.
(Child 1970: 8)
The 90-plus-item inventory was completed by 387
teachers. Separate correlation matrices composed
of the inter-correlations of the 32 items on
the satisfaction scale, the 8 items in the
persons/institutions responsibility measure and the
38 items on the stress scale were factor analysed.
The procedures followed by McCormick and
Solman (1992), Principal Components, which
were subsequently rotated, parallel those we have
outlined earlier. (Readable accounts of factor
analysis may be found in Child 1970; Kerlinger
1970.)
In the factor analysis of the 8-item responsibility
for stress measure, the researchers identified three
factors. Box 25.8 shows those three factors with
what are called their ‘factor loadings’. As we have
seen, these are like correlation coefficients, ranging
from −1.0 to+1.0 andareinterpretedsimilarly.
That is to say they indicate the correlation
between the person/institution responsibility items
shown in Box 25.8, and the factors. Looking at
factor 1, ‘School structure’, for example, it can
be seen that in the 3 items loading there are,
in descending order of weight, superiors (0.85),
school organization (0.78) and peers (0.77).
‘School structure’ as a factor, the authors suggest,
is easily identified and readily explained. But
what of factor 3, ‘Teacher–student relationships’,
which includes the variables students, society and
yourself McCormick and Solman (1992) proffer
the following tentative interpretation:
An explanation for the inclusion of the variable
‘yourself’ in this factor is not readily at hand.