The Living Thing / Notebooks :

Warping and registration of curves

TBD. Various notes on a.e. continuous monotonic changes of index to align two process, and estimation thereof.

Warping, registration problems. Especially interesting for functional data analysis,

TODO: understand computational complexity of this. High, intuition suggests.

Mass transport problems - do these relate?

Warping of point processes

A special interest of mine, at the intersection of functional data analysis, point processes and warping.


Though the study of multiple realisations of point processes has been considered prior to the emergence of FDA (see, e.g., Karr [22]), treating realisations of point processes as individual data objects within a functional data analysis context is a more recent development offering important advan- tages; a key paper is that of WuMZ13 (also see Chiou and Müller [10] and ChWH05). Such data may be an object of interest in themselves (see, e.g., WuMZ13, ArMü14, WuSr12) but may also arise as landmark data in an otherwise classical functional data analysis (see, e.g., GaKn95, ArMü14). The recent surge of interest is exemplified in an upcoming discussion paper by WuSr14, whose discussion documents early progress and challenges in the field.

Other warps

Does the CTC warp-robust loss function (GFGS06) fit here?


Connectionist Temporal Classification is a loss function useful for performing supervised learning on sequence data, without needing an alignment between input data and labels. For example, CTC can be used to train end-to-end systems for speech recognition, which is how we have been using it at Baidu’s Silicon Valley AI Lab.


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Arribas-Gil, A., & Müller, H.-G. (2014) Pairwise dynamic time warping for event data. Computational Statistics & Data Analysis, 69, 255–268. DOI.
Arribas-Gil, A., & Romo, J. (2012) Robust depth-based estimation in the time warping model. Biostatistics (Oxford, England), 13(3), 398–414. DOI.
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Gillian, N., Knapp, B., & O’Modhrain, S. (2011) Recognition of multivariate temporal musical gestures using n-dimensional dynamic time warping.
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