  Complex search tasks - such as those from the Search as Learning (SAL) domain
- often result in users developing an information need composed of several
aspects. However, current models of searcher behaviour assume that individuals
have an atomic need, regardless of the task. While these models generally work
well for simpler informational needs, we argue that searcher models need to be
developed further to allow for the decomposition of a complex search task into
multiple aspects. As no searcher model yet exists that considers both aspects
and the SAL domain, we propose, by augmenting the Complex Searcher Model (CSM),
the Subtopic Aware Complex Searcher Model (SACSM) - modelling aspects as
subtopics to the user's need. We then instantiate several agents (i.e.,
simulated users), with different subtopic selection strategies, which can be
considered as different prototypical learning strategies (e.g., should I deeply
examine one subtopic at a time, or shallowly cover several subtopics?).
Finally, we report on the first large-scale simulated analysis of user
behaviours in the SAL domain. Results demonstrate that the SACSM, under certain
conditions, simulates user behaviours accurately.
