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arXiv 1505.04413stat.ML
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流形上的调和指数族

Harmonic Exponential Families on Manifolds

Taco S. Cohen, Max Welling

摘要:

在包括地球科学、分子生物学、机器人学和计算机视觉在内的一系列领域中,人们会遇到涉及流形上的随机变量的问题。目前,缺乏快速且易于训练的流形上的灵活概率模型。我们定义了一个非常灵活的类指数族分布流形上,如环面,球,旋转组,并表明,对于这些分布的对数似然的梯度可以有效地计算使用非交换的推广的快速傅立叶变换(FFT)。我们讨论应用贝叶斯相机运动估计(谐波指数家庭作为共轭先验),地震的空间分布在地球表面的建模。我们的实验结果表明,谐波密度产生显着更高的可能性比最好的竞争方法,而数量级更快的训练。

英文摘要:

In a range of fields including the geosciences, molecular biology, robotics and computer vision, one encounters problems that involve random variables on manifolds. Currently, there is a lack of flexible probabilistic models on manifolds that are fast and easy to train. We define an extremely flexible class of exponential family distributions on manifolds such as the torus, sphere, and rotation groups, and show that for these distributions the gradient of the log-likelihood can be computed efficiently using a non-commutative generalization of the Fast Fourier Transform (FFT). We discuss applications to Bayesian camera motion estimation (where harmonic exponential families serve as conjugate priors), and modelling of the spatial distribution of earthquakes on the surface of the earth. Our experimental results show that harmonic densities yield a significantly higher likelihood than the best competing method, while being orders of magnitude faster to train.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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