12,341 research outputs found
Information Presentation in Spoken Dialogue Systems
To tackle the problem of presenting a large number of options in spoken dialogue systems, we identify compelling options based on a model of user preferences, and present tradeoffs between alternative options explicitly. Multiple attractive options are structured such that the user can gradually refine her request to find the optimal tradeoff. We show that our approach presents complex tradeoffs understandably, increases overall user satisfaction, and significantly improves the user's overview of the available options. Moreover, our results suggest that presenting users with a brief summary of the irrelevant options increases users' confidence in having heard about all relevant options
Order-by-order Analytic Solution to the BFKL Equation
We propose a regularization of the BFKL equation which allows for its
solution in each order of perturbation theory by means of a sum over multiple
poles. This sum can be presented in a rather simple formula for the Fourier
transform in the azimuthal angle of the gluon Green function. In order to test
our method, we have compared a few orders in the expansion to previous results
by Del Duca, Dixon, Duhr and Pennington, finding agreement. Our formalism is
general and can be applied to other, more complicated, kernels.Comment: 23 pages, 1 figur
What would you do? An investigation of stated-response data
When analysing choices or policy impacts, economists generally rely on what people actually do, rather than what they say they would do. The "stated response" approach is treated with scepticism due, for example, to concerns regarding the effect of strategic or social considerations on what people say, and a belief that people may not adequately consider such a hypothetical question. This paper evaluates an example of this approach; the direct questioning of parents as to whether they would withdraw their children from school if the Familias en Accion education subsidies were withdrawn. Our results suggest that these concerns are not entirely invalid but that the stated responses do provide important information and correlate in the expected manner with child and household characteristics. We conclude by emphasising the importance of good question design, which may allow researchers to use the "stated response" method as a complement to more typical quantitative methodologies
Two aspects of the Regge limit in QCD: Double Logs in Exclusive observables and Infrared Effects in Cross Sections
Two relevant points related to the application of the BFKL formalism to
phenomenology are discussed. First, we have presented a set of observables
characterizing multi-jet configurations event by event (average transverse
momentum, average azimuthal angle, average ratio of jet rapidities) which can
be used to find distinct signals of BFKL dynamics at the LHC. A numerical
analysis has been shown using the Monte Carlo event generator BFKLex, modified
to include higher-order collinear corrections in addition to the
transverse-momentum implementation of the NLO kernel. We require to have two
tagged forward/backward jets in the final state. Second, the structure of the
BFKL equation changes if infrared boundary conditions are imposed when
considering the running of the coupling. The cut in the complex angular
momentum plane becomes an infinite series of Regge poles. Integrating along a
contour off the real axis we find a strong dependence of the intercepts and
collinear regions on the choice of the boundary conditions. The mean transverse
scales dominant in the gluon ladder increase. This could have interesting
phenomenological consequences.Comment: 6 pages, presented by A. Sabio Vera at the 25th International
Workshop on Deep Inelastic Scattering and Related Topics, 3-7 April 2017,
Birmingham, U
Random l-colourable structures with a pregeometry
We study finite -colourable structures with an underlying pregeometry. The
probability measure that is used corresponds to a process of generating such
structures (with a given underlying pregeometry) by which colours are first
randomly assigned to all 1-dimensional subspaces and then relationships are
assigned in such a way that the colouring conditions are satisfied but apart
from this in a random way. We can then ask what the probability is that the
resulting structure, where we now forget the specific colouring of the
generating process, has a given property. With this measure we get the
following results: 1. A zero-one law. 2. The set of sentences with asymptotic
probability 1 has an explicit axiomatisation which is presented. 3. There is a
formula (not directly speaking about colours) such that, with
asymptotic probability 1, the relation "there is an -colouring which assigns
the same colour to and " is defined by . 4. With asymptotic
probability 1, an -colourable structure has a unique -colouring (up to
permutation of the colours).Comment: 35 page
Gluon Regge trajectory at two loops from Lipatov's high energy effective action
We present the derivation of the two-loop gluon Regge trajectory using
Lipatov's high energy effective action and a direct evaluation of Feynman
diagrams. Using a gauge invariant regularization of high energy divergences by
deforming the light-cone vectors of the effective action, we determine the
two-loop self-energy of the reggeized gluon, after computing the master
integrals involved using the Mellin-Barnes representations technique. The
self-energy is further matched to QCD through a recently proposed subtraction
prescription. The Regge trajectory of the gluon is then defined through
renormalization of the reggeized gluon propagator with respect to high energy
divergences. Our result is in agreement with previous computations in the
literature, providing a non-trivial test of the effective action and the
proposed subtraction and renormalization framework.Comment: 22 page
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