Hacker Newsnew | past | comments | ask | show | jobs | submitlogin
Corrupt, sparse, irregular and ugly: Deep learning on time series (notion.so)
92 points by dsalaj on June 21, 2020 | hide | past | favorite | 6 comments


Was prepared for an introduction to some novel never-before-seen method near the end, but this was a nice and well-structured summary regardless! Wanted to tack on a couple of questions/thoughts:

1. Is the author familiar with all of the recent work around neural differential equations? Latent (Neural) ODEs[1] and Neural Controlled Differential Equations[2] are already able to match or exceed the performance of GRU-D when working with certain sparse and irregularly-sampled time series.

2. More of a nitpick, but most of the models covered as working with EHR data are using clinical data instead of raw physiological signals. For example, measurements from a high-frequency physiological waveform such as an ECG are usually synthesized into something like a per-minute heart rate in a medical record. Most research working with physiological signals directly is using either traditional signal processing approaches or some form of CNN (this includes 1-D resnets and wavenet-like architectures). RNNs do pop up occasionally when dealing with dramatically downsampled signals, but seem to suffer pretty badly from catastrophic forgetting and other issues when run on longer, higher-frequency data.

[1] http://papers.nips.cc/paper/8773-latent-ordinary-differentia... [2] https://arxiv.org/abs/2005.08926


Yeah, irregularly spaced time series data seemed to be the killer app of Neural ODEs according to my understanding.


Thanks for the great tips! I'll make sure to update the content with these points.


Didn’t realise Notion was being used to write blog posts too. It does make quite a bit of sense to use the same interface to take notes and then occasionally combine and refine those into a blog post.


That use case has been the topic of a recent, well-received Show HN thread: https://news.ycombinator.com/item?id=23514682


Thanks for sharing the link, that looks fantastic!




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: