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arXiv · 1712.00206

Distributed Stratified Locality Sensitive Hashing for Critical Event Prediction in the Cloud

Alessandro De Palma·Erik Hemberg·Una-May O'Reilly
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Abstract

The availability of massive healthcare data repositories calls for efficient tools for data-driven medicine. We introduce a distributed system for Stratified Locality Sensitive Hashing to perform fast similarity-based prediction on large medical waveform datasets. Our implementation, for an ICU use case, prioritizes latency over throughput and is targeted at a cloud environment. We demonstrate our system on Acute Hypotensive Episode prediction from Arterial Blood Pressure waveforms. On a dataset of $1.37$ million points, we show scaling up to $40$ processors and a $21\times$ speedup in number of comparisons to parallel exhaustive search at the price of a $10\%$ Matthews correlation coefficient (MCC) loss. Furthermore, if additional MCC loss can be tolerated, our system achieves speedups up to two orders of magnitude.

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Alessandro De Palma, Erik Hemberg, Una-May O'Reilly. 2017-12-01. Distributed Stratified Locality Sensitive Hashing for Critical Event Prediction in the Cloud. https://arxiv.org/abs/1712.00206

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