29,658 research outputs found
Prompt Delay
Delay games are two-player games of infinite duration in which one player may
delay her moves to obtain a lookahead on her opponent's moves. Recently, such
games with quantitative winning conditions in weak MSO with the unbounding
quantifier were studied, but their properties turned out to be unsatisfactory.
In particular, unbounded lookahead is in general necessary. Here, we study
delay games with winning conditions given by Prompt-LTL, Linear Temporal Logic
equipped with a parameterized eventually operator whose scope is bounded. Our
main result shows that solving Prompt-LTL delay games is complete for
triply-exponential time. Furthermore, we give tight triply-exponential bounds
on the necessary lookahead and on the scope of the parameterized eventually
operator. Thus, we identify Prompt-LTL as the first known class of well-behaved
quantitative winning conditions for delay games. Finally, we show that applying
our techniques to delay games with \omega-regular winning conditions answers
open questions in the cases where the winning conditions are given by
non-deterministic, universal, or alternating automata
How Much Lookahead is Needed to Win Infinite Games?
Delay games are two-player games of infinite duration in which one player may
delay her moves to obtain a lookahead on her opponent's moves. For
-regular winning conditions it is known that such games can be solved
in doubly-exponential time and that doubly-exponential lookahead is sufficient.
We improve upon both results by giving an exponential time algorithm and an
exponential upper bound on the necessary lookahead. This is complemented by
showing EXPTIME-hardness of the solution problem and tight exponential lower
bounds on the lookahead. Both lower bounds already hold for safety conditions.
Furthermore, solving delay games with reachability conditions is shown to be
PSPACE-complete.
This is a corrected version of the paper https://arxiv.org/abs/1412.3701v4
published originally on August 26, 2016
Measuring consumption smoothing in CEX data
This paper proposes and implements a new method of measuring the degree of consumption smoothing using data from the Consumer Expenditure Survey. The structure of this Survey is such that estimators previously used in the literature are inconsistent, simply because income is measured annually and consumption is measured quarterly. We impose an AR(1) structure on the income process to obtain a proxy for quarterly income through a projection on annual income. By construction, this proxy gives rise to a measurement error which is orthogonal to the proxy itself - as opposed to the unobserved regressor - leading to a consistent estimator. We contrast our estimates with the output of two estimators used in the literature. We show that while the first (OLS) estimator tends to overstate the degree of risk sharing, the second (IV) estimator grossly understates it <br><br> Keywords; risk sharing, consumption smoothing, income risk, projection
Discovering Scholarly Orphans Using ORCID
Archival efforts such as (C)LOCKSS and Portico are in place to ensure the
longevity of traditional scholarly resources like journal articles. At the same
time, researchers are depositing a broad variety of other scholarly artifacts
into emerging online portals that are designed to support web-based
scholarship. These web-native scholarly objects are largely neglected by
current archival practices and hence they become scholarly orphans. We
therefore argue for a novel paradigm that is tailored towards archiving these
scholarly orphans. We are investigating the feasibility of using Open
Researcher and Contributor ID (ORCID) as a supporting infrastructure for the
process of discovery of web identities and scholarly orphans for active
researchers. We analyze ORCID in terms of coverage of researchers, subjects,
and location and assess the richness of its profiles in terms of web identities
and scholarly artifacts. We find that ORCID currently lacks in all considered
aspects and hence can only be considered in conjunction with other discovery
sources. However, ORCID is growing fast so there is potential that it could
achieve a satisfactory level of coverage and richness in the near future.Comment: 10 pages, 5 figures, 5 tables accepted for publication at JCDL 201
On the Number of Membranes in Unary P Systems
We consider P systems with a linear membrane structure working on objects
over a unary alphabet using sets of rules resembling homomorphisms. Such a
restricted variant of P systems allows for a unique minimal representation of
the generated unary language and in that way for an effective solution of the
equivalence problem. Moreover, we examine the descriptional complexity of unary
P systems with respect to the number of membranes
Extending Sitemaps for ResourceSync
The documents used in the ResourceSync synchronization framework are based on
the widely adopted document format defined by the Sitemap protocol. In order to
address requirements of the framework, extensions to the Sitemap format were
necessary. This short paper describes the concerns we had about introducing
such extensions, the tests we did to evaluate their validity, and aspects of
the framework to address them.Comment: 4 pages, 6 listings, accepted at JCDL 201
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