17,096 research outputs found
Fully Dynamic Connectivity in Amortized Expected Time
Dynamic connectivity is one of the most fundamental problems in dynamic graph
algorithms. We present a randomized Las Vegas dynamic connectivity data
structure with amortized expected update time and
worst case query time, which comes very close to the
cell probe lower bounds of Patrascu and Demaine (2006) and Patrascu and Thorup
(2011)
Weighted dynamic finger in binary search trees
It is shown that the online binary search tree data structure GreedyASS
performs asymptotically as well on a sufficiently long sequence of searches as
any static binary search tree where each search begins from the previous search
(rather than the root). This bound is known to be equivalent to assigning each
item in the search tree a positive weight and bounding the search
cost of an item in the search sequence by
amortized. This result is the strongest finger-type bound to be proven for
binary search trees. By setting the weights to be equal, one observes that our
bound implies the dynamic finger bound. Compared to the previous proof of the
dynamic finger bound for Splay trees, our result is significantly shorter,
stronger, simpler, and has reasonable constants.Comment: An earlier version of this work appeared in the Proceedings of the
Twenty-Seventh Annual ACM-SIAM Symposium on Discrete Algorithm
GP-HD: Using Genetic Programming to Generate Dynamical Systems Models for Health Care
The huge wealth of data in the health domain can be exploited to create
models that predict development of health states over time. Temporal learning
algorithms are well suited to learn relationships between health states and
make predictions about their future developments. However, these algorithms:
(1) either focus on learning one generic model for all patients, providing
general insights but often with limited predictive performance, or (2) learn
individualized models from which it is hard to derive generic concepts. In this
paper, we present a middle ground, namely parameterized dynamical systems
models that are generated from data using a Genetic Programming (GP) framework.
A fitness function suitable for the health domain is exploited. An evaluation
of the approach in the mental health domain shows that performance of the model
generated by the GP is on par with a dynamical systems model developed based on
domain knowledge, significantly outperforms a generic Long Term Short Term
Memory (LSTM) model and in some cases also outperforms an individualized LSTM
model
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