Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Searching for a source without gradients: how good is infotaxis and how
  to beat it   Infotaxis is a popular search algorithm designed to track a source of odor in
a turbulent environment using information provided by odor detections. To
exemplify its capabilities, the source-tracking task was framed as a partially
observable Markov decision process consisting in finding, as fast as possible,
a stationary target hidden in a 2D grid using stochastic partial observations
of the target location. Here we provide an extended review of infotaxis,
together with a toolkit for devising better strategies. We first characterize
the performance of infotaxis in domains from 1D to 4D. Our results show that,
while being suboptimal, infotaxis is reliable (the probability of not reaching
the source approaches zero), efficient (the mean search time scales as expected
for the optimal strategy), and safe (the tail of the distribution of search
times decays faster than any power law, though subexponentially). We then
present three possible ways of beating infotaxis, all inspired by methods used
in artificial intelligence: tree search, heuristic approximation of the value
function, and deep reinforcement learning. The latter is able to find, without
any prior human knowledge, the (near) optimal strategy. Altogether, our results
provide evidence that the margin of improvement of infotaxis toward the optimal
strategy gets smaller as the dimensionality increases.

31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex