Qualitative_data_analysis

Table 12.4 Boolean operators for category retrievals
this means BOTH categories have been assigned and it excludes those where only
one OR the other has been applied. In our other retrieval we asked the computer to
collect all examples where one category BUT NOT the other has been assigned to
the data. Using ‘X’ and ‘Y’ for our categories, we can see that our retrievals are based
on the following operations:
retrieve all ‘X’ AND ‘Y’
retrieve all ‘X’ NOT ‘Y’
These are often called ‘boolean’ operators after the nineteenth century logician,
George Boole, who first distinguished them. There is another operator we may find
useful as a basis for retrievals:
retrieve all ‘X’ OR ‘Y’
MAKING CONNECTIONS 183
This would allow us to retrieve all the data which has been assigned to either of two
different categories. For example, we could retrieve all the databits assigned to
‘dentist suffering’ and ‘patient suffering’. Notice that in ordinary language, we tend
to use ‘and’ rather than ‘or’ when we refer to retrieving all the databits for each of the
categories—meaning ‘all X and all Y’. Confusion arises if we think about the results
of the retrieval—which will include all ‘X’ and all ‘Y’—rather than the decisions on
which it is based. To avoid confusion, we need to consider how the retrieval
‘operates’ on each databit. It is this decision which we must be clear about: i.e. do
we include this databit or not? The boolean operators provide a logical basis for
deciding on inclusion or exclusion in terms of how our categories have been
assigned (Table 12.4)
Cross-tabulations based on such retrievals involve looking for connections where
categories do or do not concur. The evidence these retrievals produce is embedded
within each databit. The databits within each cell have no relationship to each
other, other than that they have been assigned to the same category or categories.