4,762 research outputs found
Local Subspace-Based Outlier Detection using Global Neighbourhoods
Outlier detection in high-dimensional data is a challenging yet important
task, as it has applications in, e.g., fraud detection and quality control.
State-of-the-art density-based algorithms perform well because they 1) take the
local neighbourhoods of data points into account and 2) consider feature
subspaces. In highly complex and high-dimensional data, however, existing
methods are likely to overlook important outliers because they do not
explicitly take into account that the data is often a mixture distribution of
multiple components.
We therefore introduce GLOSS, an algorithm that performs local subspace
outlier detection using global neighbourhoods. Experiments on synthetic data
demonstrate that GLOSS more accurately detects local outliers in mixed data
than its competitors. Moreover, experiments on real-world data show that our
approach identifies relevant outliers overlooked by existing methods,
confirming that one should keep an eye on the global perspective even when
doing local outlier detection.Comment: Short version accepted at IEEE BigData 201
EU ENLARGEMENT TO TURKEY: POTENTIAL IMPACTS ON AGRICULTURAL MARKETS AND HOW THEY ARE SHAPED BY CHANGES IN MACROECONOMIC CONDITIONS
The potential accession of Turkey to the EU, and the related adoption of the CAP by Turkey, is expected to influence agricultural markets in both the EU and Turkey. The extent of the accession impacts depends on the one hand on the way the CAP will be implemented in Turkey, while on the other hand impacts are expected to be also shaped by macroeconomic conditions (like exchange rates, GDP growth and inflation levels). In this paper we provide a comprehensive model-based assessment of the potential impacts on agricultural markets of a Turkish accession to the EU. We first assess the impacts under the assumption of standard macroeconomic projections, then we analyse how a different TL/Euro exchange rate, a doubling of the Turkish inflation rate or a doubling of the Turkish GDP growth rate would influence the accession impacts. Results of the Turkish EU-membership simulation show that the impacts on agricultural markets in Turkey are significant, while effects on EU markets are rather limited. The main impact on Turkish agriculture is a reduction of producer prices. With market prices and produced quantities declining, and as the coupled Turkish direct payments and the input subsidies will be replaced by lower payments of the CAP, agricultural income is expected to be reduced especially for Turkish crop producers (except for tobacco). In contrast, accession effects on the Turkish livestock sector are projected to be positive, mainly due to lower feed costs. Furthermore, the demand levels of most commodities are projected to increase due to lower prices, thus Turkish consumers are expected to gain from an accession to the EU. The further analysis reveals that in particular a depreciation of the Turkish lira alters the results of the accession scenario.Turkey, EU enlargement, agricultural markets, macro economy, AGMEMOD Zusammenfassung, Türkei, EU Erweiterung, Agrarmärkte, Makroökonomie, AGMEMOD, Agribusiness, Agricultural and Food Policy, Agricultural Finance,
ICT, Innovation and Business Performance in Services: Evidence for Germany and the Netherlands
Using panel data for German and Dutch firms from the services sector, this paper analyses the importance of ICT capital deepening and innovation for productivity. We employ a model that takes into account that innovation and ICT use may be complementary. The results show that the contribution of ICT capital deepening is raised when firms combine ICT use and technological innovations on a more permanent basis. Moreover, the joint impact of ICT use and permanent technological innovation on productivity appears to be of the same order of magnitude in the two countries. However, the direct impacts of innovation on multi-factor productivity seems to be more robust for Germany than for the Netherlands. --Productivity,Information and Communication Technologies,Innovation,Services,Panel Data
The physiology of movement
Movement, from foraging to migration, is known to be under the influence of the environment. The translation of environmental cues to individual movement decision making is determined by an individual's internal state and anticipated to balance costs and benefits. General body condition, metabolic and hormonal physiology mechanistically underpin this internal state. These physiological determinants are tightly, and often genetically linked with each other and hence central to a mechanistic understanding of movement. We here synthesise the available evidence of the physiological drivers and signatures of movement and review (1) how physiological state as measured in its most coarse way by body condition correlates with movement decisions during foraging, migration and dispersal, (2) how hormonal changes underlie changes in these movement strategies and (3) how these can be linked to molecular pathways. We reveale that a high body condition facilitates the efficiency of routine foraging, dispersal and migration. Dispersal decision making is, however, in some cases stimulated by a decreased individual condition. Many of the biotic and abiotic stressors that induce movement initiate a physiological cascade in vertebrates through the production of stress hormones. Movement is therefore associated with hormone levels in vertebrates but also insects, often in interaction with factors related to body or social condition. The underlying molecular and physiological mechanisms are currently studied in few model species, and show -in congruence with our insights on the role of body condition- a central role of energy metabolism during glycolysis, and the coupling with timing processes during migration. Molecular insights into the physiological basis of movement remain, however, highly refractory. We finalise this review with a critical reflection on the importance of these physiological feedbacks for a better mechanistic understanding of movement and its effects on ecological dynamics at all levels of biological organization
Resistance risk assessment of the novel complex II inhibitor pyflubumide in the polyphagous pest Tetranychus urticae
Pyflubumide is a novel selective carboxanilide acaricide that inhibits mitochondrial complex II of spider mite species such as Tetranychus urticae. We explored the baseline toxicity and potential cross-resistance risk of pyflubumide in a reference panel of T. urticae strains resistant to various acaricides with different modes of action. A cyenopyrafen-resistant strain (JPR) was identified as the only strain with low-to-moderate level of cross-resistance to pyflubumide (LC50 = 49.07 mg/L). In a resistance risk assessment approach, JPR was subsequently selected which led to two highly resistant strains JPR-R1 (RR = 466.7) and JPR-R2 (RR = 614.8). Interestingly, compared to adult females, resistance was much less pronounced in adult males and eggs of the two JPR-R strains. In order to elucidate resistance mechanisms, we first sequenced the complex II subunits in susceptible and resistant strains, but target-site insensitivity could not be detected. In contrast, synergism/antagonism experiments strongly suggested that cytochrome P450 monooxygenases are involved in pyflubumide resistance. We therefore conducted genome-wide gene expression experiments to investigate constitutive and induced expression patterns and documented the overexpression of five cytochrome P450 and four carboxyl/choline esterase genes in the JPR-R strains after pyflubumide exposure. Together, we provide a first resistance risk assessment of a novel complex II inhibitor and provide first evidence for metabolic resistance mediated by cytochrome P450s in T. urticae
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