Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Approximately Efficient Bilateral Trade   We study bilateral trade between two strategic agents. The celebrated result
of Myerson and Satterthwaite states that in general, no incentive-compatible,
individually rational and weakly budget balanced mechanism can be efficient.
I.e., no mechanism with these properties can guarantee a trade whenever buyer
value exceeds seller cost. Given this, a natural question is whether there
exists a mechanism with these properties that guarantees a constant fraction of
the first-best gains-from-trade, namely a constant fraction of the
gains-from-trade attainable whenever buyer's value weakly exceeds seller's
cost. In this work, we positively resolve this long-standing open question on
constant-factor approximation, mentioned in several previous works, using a
simple mechanism.

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The categories of this paper are: comp-gas
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The categories of this paper are: solv-int
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
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The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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The categories of this paper are: nlin
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The categories of this paper are: cmp-lg
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The categories of this paper are: eess
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The categories of this paper are: nucl-th
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The categories of this paper are: nucl-ex
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The categories of this paper are: astro-ph
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The categories of this paper are: ao-sci