Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Experimental design for MRI by greedy policy search   In today's clinical practice, magnetic resonance imaging (MRI) is routinely
accelerated through subsampling of the associated Fourier domain. Currently,
the construction of these subsampling strategies - known as experimental design
- relies primarily on heuristics. We propose to learn experimental design
strategies for accelerated MRI with policy gradient methods. Unexpectedly, our
experiments show that a simple greedy approximation of the objective leads to
solutions nearly on-par with the more general non-greedy approach. We offer a
partial explanation for this phenomenon rooted in greater variance in the
non-greedy objective's gradient estimates, and experimentally verify that this
variance hampers non-greedy models in adapting their policies to individual MR
images. We empirically show that this adaptivity is key to improving
subsampling designs.

24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci