learning qualitative model
Learning Qualitative Models from Numerical Data: Extended abstract
Žabkar, Jure (University of Ljubljana) | Možina, Martin (University of Ljubljana) | Bratko, Ivan (University of Ljubljana) | Demšar, Janez (University of Ljubljana)
Qualitative models are predictive models that describe how changes in values of input variables affect the output variable in qualitative terms, e.g. increasing or decreasing. We describe Padé, a new method for qualitative learning which estimates partial derivatives of the target function from training data and uses them to induce qualitative models of the target function. We formulated three methods for computation of derivatives, all based on using linear regression on local neighbourhoods. The methods were empirically tested on artificial and real-world data. We also provide a case study which shows how the developed methods can be used in practice.
Learning Qualitative Models by Demonstration
Hinrichs, Thomas R. (Northwestern University) | Forbus, Kenneth D. (Northwestern University)
Creating software agents that learn interactively requires the ability to learn from a small number of trials, extracting general, flexible knowledge that can drive behavior from observation and interaction. We claim that qualitative models provide a useful intermediate level of causal representation for dynamic domains, including the formulation of strategies and tactics. We argue that qualitative models are quickly learnable, and enable model-based reasoning techniques to be used to recognize, operationalize, and construct more strategic knowledge. This paper describes an approach to incrementally learning qualitative influences by demonstration in the context of a strategy game. We show how the learned model can help a system play by enabling it to explain which actions could contribute to maximizing a quantitative goal. We also show how reasoning about the model allows it to reformulate a learning problem to address delayed effects and credit assignment, such that it can improve its performance on more strategic tasks such as city placement.