Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonlinear Quality of Life Index   We present details of the analysis of the nonlinear quality of life index for
171 countries. This index is based on four indicators: GDP per capita by
Purchasing Power Parities, Life expectancy at birth, Infant mortality rate, and
Tuberculosis incidence. We analyze the structure of the data in order to find
the optimal and independent on expert's opinion way to map several numerical
indicators from a multidimensional space onto the one-dimensional space of the
quality of life. In the 4D space we found a principal curve that goes "through
the middle" of the dataset and project the data points on this curve. The order
along this principal curve gives us the ranking of countries. Projection onto
the principal curve provides a solution to the classical problem of
unsupervised ranking of objects. It allows us to find the independent on
expert's opinion way to project several numerical indicators from a
multidimensional space onto the one-dimensional space of the index values. This
projection is, in some sense, optimal and preserves as much information as
possible. For computation we used ViDaExpert, a tool for visualization and
analysis of multidimensional vectorial data (arXiv:1406.5550).

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The categories of this paper are: gr-qc
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The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
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The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
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The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: cmp-lg