<p> Learning to predict how an environment will evolve and the consequences of one’s actions is an important ability for autonomous agents, and can enable planning with relatively few interactions with the environment which may be slow or costly. However, learning an accurate forward model is often difficult in practice due to several features often present in complex environments. First, many environments exhibit long-term dependencies which require the system to learn to record and maintain relevant information in its memory over long timescales. Second, the envi- ronment may only be partially observed, and the aspects of the environment which are observed may depend on parts of the environment which are hidden. Third, many observed processes contain some form of apparent or inherent stochasticity, which makes the task of predicting future states ill-defined. </p><p> In this thesis, we propose approaches to tackle and better understand these different challenges associated with learning predictive models of the environment and using them for planning. We first provide an analysis of recurrent neural network (RNN) memory, which sheds light on the mechanisms by which RNNs are able to store different types of information in their memory over long timescales through the analysis of two synthetic benchmark tasks. We then introduce a new neural network architecture which keeps an estimate of the state of the environment in its memory, and can deal with partial observability by reasoning based on what is observed. We next present a new method for performing planning using a learned model of the environment with both discrete and continuous actions. Finally, we propose an approach for model-based planning in the presence of both environment uncertainty and model uncertainty, and evaluate it on a new real-world dataset and environment with applications to autonomous driving.</p><p>
| Identifer | oai:union.ndltd.org:PROQUEST/oai:pqdtoai.proquest.com:10928805 |
| Date | 17 November 2018 |
| Creators | Henaff, Mikael |
| Publisher | New York University |
| Source Sets | ProQuest.com |
| Language | English |
| Detected Language | English |
| Type | thesis |
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