"ad hoc category" is correct and usable in written English.
It is often used to describe a group or category created for a specific purpose, often on the fly or for a particular purpose. For example, "The team created an ad hoc category of personnel to handle the unexpected surge in customer inquiries."
Another important thing to note is that ad hoc categories can turn into more permanent goal-related categories when they are used more often (Barsalou 1991).
Whereas concepts have only one place in the natural categorization classification, they can be simultaneously part of a number of ad hoc categories.
For example, although petrol will be by default a member of the category fuel, it can end up in several ad hoc categories because of the different attributes of the concept.
The latter task employs typical exemplars (lion) of well defined semantic categories (animal, vegetable), whereas Damian's task used ad hoc categories (bigger or smaller than a 20 cm square).
Combinations of the quantitative structure-based models into ITSs (Hartung et al. 2013b), sometimes (OECD 2012a, b) also described as Integrated Approaches to Testing and Assessment (IATA) (Fig. 2), are technically demanding, but an important goal, since it may provide a more objective and robust approach compared to ad hoc categories and groups formed based on a narrative of available data.
After this step the database included 346 items To facilitate the detection of redundant items in this large item set, all items were first classified into ad-hoc categories (e.g. physical, social, household, energy) that were set up by the reviewers.
In Table 3, we present the definitions for the named ad hoc decision-making categories.
Table 2 summarises the named ad hoc decision-making categories, the frequencies and percentages of our coding, the participants in the study, the total observation times and intercoder reliability values with Cohen's κ values.
