3,771 research outputs found
Long and Diverse Text Generation with Planning-based Hierarchical Variational Model
Existing neural methods for data-to-text generation are still struggling to
produce long and diverse texts: they are insufficient to model input data
dynamically during generation, to capture inter-sentence coherence, or to
generate diversified expressions. To address these issues, we propose a
Planning-based Hierarchical Variational Model (PHVM). Our model first plans a
sequence of groups (each group is a subset of input items to be covered by a
sentence) and then realizes each sentence conditioned on the planning result
and the previously generated context, thereby decomposing long text generation
into dependent sentence generation sub-tasks. To capture expression diversity,
we devise a hierarchical latent structure where a global planning latent
variable models the diversity of reasonable planning and a sequence of local
latent variables controls sentence realization. Experiments show that our model
outperforms state-of-the-art baselines in long and diverse text generation.Comment: To appear in EMNLP 201
SALSA-TEXT : self attentive latent space based adversarial text generation
Inspired by the success of self attention mechanism and Transformer
architecture in sequence transduction and image generation applications, we
propose novel self attention-based architectures to improve the performance of
adversarial latent code- based schemes in text generation. Adversarial latent
code-based text generation has recently gained a lot of attention due to their
promising results. In this paper, we take a step to fortify the architectures
used in these setups, specifically AAE and ARAE. We benchmark two latent
code-based methods (AAE and ARAE) designed based on adversarial setups. In our
experiments, the Google sentence compression dataset is utilized to compare our
method with these methods using various objective and subjective measures. The
experiments demonstrate the proposed (self) attention-based models outperform
the state-of-the-art in adversarial code-based text generation.Comment: 10 pages, 3 figures, under review at ICLR 201
Neural representation in active inference: using generative models to interact with -- and understand -- the lived world
This paper considers neural representation through the lens of active
inference, a normative framework for understanding brain function. It delves
into how living organisms employ generative models to minimize the discrepancy
between predictions and observations (as scored with variational free energy).
The ensuing analysis suggests that the brain learns generative models to
navigate the world adaptively, not (or not solely) to understand it. Different
living organisms may possess an array of generative models, spanning from those
that support action-perception cycles to those that underwrite planning and
imagination; namely, from "explicit" models that entail variables for
predicting concurrent sensations, like objects, faces, or people - to
"action-oriented models" that predict action outcomes. It then elucidates how
generative models and belief dynamics might link to neural representation and
the implications of different types of generative models for understanding an
agent's cognitive capabilities in relation to its ecological niche. The paper
concludes with open questions regarding the evolution of generative models and
the development of advanced cognitive abilities - and the gradual transition
from "pragmatic" to "detached" neural representations. The analysis on offer
foregrounds the diverse roles that generative models play in cognitive
processes and the evolution of neural representation
Predictive World Models from Real-World Partial Observations
Cognitive scientists believe adaptable intelligent agents like humans perform
reasoning through learned causal mental simulations of agents and environments.
The problem of learning such simulations is called predictive world modeling.
Recently, reinforcement learning (RL) agents leveraging world models have
achieved SOTA performance in game environments. However, understanding how to
apply the world modeling approach in complex real-world environments relevant
to mobile robots remains an open question. In this paper, we present a
framework for learning a probabilistic predictive world model for real-world
road environments. We implement the model using a hierarchical VAE (HVAE)
capable of predicting a diverse set of fully observed plausible worlds from
accumulated sensor observations. While prior HVAE methods require complete
states as ground truth for learning, we present a novel sequential training
method to allow HVAEs to learn to predict complete states from partially
observed states only. We experimentally demonstrate accurate spatial structure
prediction of deterministic regions achieving 96.21 IoU, and close the gap to
perfect prediction by 62% for stochastic regions using the best prediction. By
extending HVAEs to cases where complete ground truth states do not exist, we
facilitate continual learning of spatial prediction as a step towards realizing
explainable and comprehensive predictive world models for real-world mobile
robotics applications. Code is available at
https://github.com/robin-karlsson0/predictive-world-models.Comment: Accepted for IEEE MOST 202
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