32,763 research outputs found
Complexity Hierarchies Beyond Elementary
We introduce a hierarchy of fast-growing complexity classes and show its
suitability for completeness statements of many non elementary problems. This
hierarchy allows the classification of many decision problems with a
non-elementary complexity, which occur naturally in logic, combinatorics,
formal languages, verification, etc., with complexities ranging from simple
towers of exponentials to Ackermannian and beyond.Comment: Version 3 is the published version in TOCT 8(1:3), 2016. I will keep
updating the catalogue of problems from Section 6 in future revision
Dominance Measuring Method Performance under Incomplete Information about Weights.
In multi-attribute utility theory, it is often not easy to elicit precise values for the scaling weights representing the relative importance of criteria. A very widespread approach is to gather incomplete information. A recent approach for dealing with such situations is to use information about each alternative?s intensity of dominance, known as dominance measuring methods. Different dominancemeasuring methods have been proposed, and simulation studies have been carried out to compare these methods with each other and with other approaches but only when ordinal information about weights is available. In this paper, we useMonte Carlo simulation techniques to analyse the performance of and adapt such methods to deal with weight intervals, weights fitting independent normal probability distributions orweights represented by fuzzy numbers.Moreover, dominance measuringmethod performance is also compared with a widely used methodology dealing with incomplete information on weights, the stochastic multicriteria acceptability analysis (SMAA). SMAA is based on exploring the weight space to describe the evaluations that would make each alternative the preferred one
Visitors to the city of Évora: Who are they?
Nowadays, driven by multiple factors, tourist demand presents patterned behaviour which is subdivided into several typologies according to destination, product consumed and visitor profile features. In the case of cultural tourism, a good example is that of historic
cities, which have their own cultural identity and heritage, and compete to make themselves different
from one another through many marketing strategies. This study presents the profile of
visitors to the World Heritage City of Évora, including their travel motivations and level of satisfaction with the attributes. Subsequently, the main purpose of this study is to determine
the cultural profile of visitors to the World Heritage City of Évora. The data collection technique applied was a visitor survey. The process adopted for the sample definition was a probabilistic sampling, namely the adoption of a stratified sampling plan, by place of residence.
Further analysis shows that the most important motivations for visitors in selecting Évora are leisure, heritage/monuments and having a new cultural experience. However they indicate the
fact that Évora is considered World Heritage City by UNESCO did influence the decision to
visit this destination. Several findings provide the opportunity to establish adequate managerial and marketing strategies to suit the needs of the visitors
QCBA: Postoptimization of Quantitative Attributes in Classifiers based on Association Rules
The need to prediscretize numeric attributes before they can be used in
association rule learning is a source of inefficiencies in the resulting
classifier. This paper describes several new rule tuning steps aiming to
recover information lost in the discretization of numeric (quantitative)
attributes, and a new rule pruning strategy, which further reduces the size of
the classification models. We demonstrate the effectiveness of the proposed
methods on postoptimization of models generated by three state-of-the-art
association rule classification algorithms: Classification based on
Associations (Liu, 1998), Interpretable Decision Sets (Lakkaraju et al, 2016),
and Scalable Bayesian Rule Lists (Yang, 2017). Benchmarks on 22 datasets from
the UCI repository show that the postoptimized models are consistently smaller
-- typically by about 50% -- and have better classification performance on most
datasets
- …