Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Empirically Classifying Network Mechanisms   Network models are used to study interconnected systems across many physical,
biological, and social disciplines. Such models often assume a particular
network-generating mechanism, which when fit to data produces estimates of
mechanism-specific parameters that describe how systems function. For instance,
a social network model might assume new individuals connect to others with
probability proportional to their number of pre-existing connections
('preferential attachment'), and then estimate the disparity in interactions
between famous and obscure individuals with similar qualifications. However,
without a means of testing the relevance of the assumed mechanism, conclusions
from such models could be misleading. Here we introduce a simple empirical
approach which can mechanistically classify arbitrary network data. Our
approach compares empirical networks to model networks from a user-provided
candidate set of mechanisms, and classifies each network--with high
accuracy--as originating from either one of the mechanisms or none of them. We
tested 373 empirical networks against five of the most widely studied network
mechanisms and found that most (228) were unlike any of these mechanisms. This
raises the possibility that some empirical networks arise from mixtures of
mechanisms. We show that mixtures are often unidentifiable because different
mixtures can produce functionally equivalent networks. In such systems, which
are governed by multiple mechanisms, our approach can still accurately predict
out-of-sample functional properties.

2
The categories of this paper are: math
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph