Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Bayesian Approach to Comparing Cosmic Ray Energy Spectra   A common problem in ultra-high energy cosmic ray physics is the comparison of
energy spectra. The question is whether the spectra from two experiments or two
regions of the sky agree within their statistical and systematic uncertainties.
We develop a method to directly compare energy spectra for ultra-high energy
cosmic rays from two different regions of the sky in the same experiment
without reliance on agreement with a theoretical model of the energy spectra.
The consistency between the two spectra is expressed in terms of a Bayes
factor, defined here as the ratio of the likelihood of the two-parent source
hypothesis to the likelihood of the one-parent source hypothesis. Unlike other
methods, for example chi^2 tests, the Bayes factor allows for the calculation
of the posterior odds ratio and correctly accounts for non-Gaussian
uncertainties. The latter is particularly important at the highest energies,
where the number of events is very small.

29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org