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The present study investigated how information about situational characteristics typically encountered by backcountry recreationists influenced their perceived likelihood of skiing backcountry slopes exposed to avalanche danger. Sensation seeking and previous direct and indirect experiences with avalanche accidents were evaluated as relevant individual predictors. Data was collected by implementing randomized textual scenarios, using a sample of 376 backcountry recreationists from North-Italy (84% male; age: M = 39.68, SD = 9.72). Results of multilevel analyses indicated that forecasted avalanche danger level and slope inclination were associated with lower self-reported likelihood of skiing the slopes, while sensation-seeking, familiarity with the slope area, the availability of safety equipment and the presence of tracks on the slope were positively related with selfreported likelihood of skiing. Previous direct involvement in avalanche accidents was also positively associated with perceived likelihood of skiing, suggesting the existence of confidence-enhancing effects related to avalanche survival experiences.

When there is an interest in tracking longitudinal trends of student educational achievement using standardized tests, the most common linking approach generally involves the inclusion of a common set of items across adjacent test administrations. However, this approach may not be feasible in the context of high-stakes testing due to undesirable exposure of administered items. In this paper, we propose an alternative design, which allows for the equating of multiple operational tests with no items in common based on the inclusion of common items in an anchor test administered in a post-test condition. We tested this approach using data from the assessment program implemented in Italy by the National Institute for the Educational Evaluation of Instruction and Training for the years 2010–2012, and from a convenience sample of 832 8th grade students. Additionally, we investigated the impact on functioning of common items of varying item position and orders across test forms. Linking of tests was performed using multiple-group Item Response Theory modeling. Results of linking indicated that operational tests showed little variation in difficulty over the years. Investigation of item position and order effects showed that changes in item position closer to the end of the test, as well as the positioning of difficult items at the beginning or in the middle section of a test lead to a significant increase in difficulty of common items. Overall, findings indicate that this approach represents a viable linking design, which can be useful when the inclusion of common items across operational tests is not possible. The impact of differential item functioning of common items on equating error and the ability to detect ability trends is discussed.

Empirical auto-tuning and machine learning techniques have been showing high potential to improve execution time, power consumption, code size, reliability and other important metrics of various applications for more than two decades. However, they are still far from widespread production use due to lack of native support for auto-tuning in an ever changing and complex software and hardware stack, large and multi-dimensional optimization spaces, excessively long exploration times, and lack of unified mechanisms for preserving and sharing of optimization knowledge and research material. We present a possible collaborative approach to solve above problems using Collective Mind knowledge management system. In contrast with previous cTuning framework, this modular infrastructure allows to preserve and share through the Internet the whole auto-tuning setups with all related artifacts and their software and hardware dependencies besides just performance data. It also allows to gradually structure, systematize and describe all available research material including tools, benchmarks, data sets, search strategies and machine learning models. Researchers can take advantage of shared components and data with extensible meta-description to quickly and collaboratively validate and improve existing auto-tuning and benchmarking techniques or prototype new ones. The community can now gradually learn and improve complex behavior of all existing computer systems while exposing behavior anomalies or model mispredictions to an interdisciplinary community in a reproducible way for further analysis. We present several practical, collaborative and model-driven auto-tuning scenarios. We also decided to release all material atc-mind.org/repoto set up an example for a collaborative and reproducible research as well as our new publication model in computer engineering where experimental results are continuously shared and validated by the community.

We consider the problem of managing a hybrid computing infrastructure whose processing elements are comprised of in-house dedicated machines, virtual machines acquired on-demand from a cloud computing provider through short-term reservation contracts, and virtual machines made available by the remote peers of a best-effort peer-to-peer (P2P) grid. Each of these resources has different cost basis and associated quality of service guarantees. The applications that run in this hybrid infrastructure are characterized by a utility function: the utility gained with the completion of an application depends on the time taken to execute it. We take a business-driven approach to manage this infrastructure, aiming at maximizing the profit yielded, that is, the utility produced as a result of the applications that are run minus the cost of the computing resources that are used to run them. We propose a heuristic to be used by a contract planner agent that establishes the contracts with the cloud computing provider to balance the cost of running an application and the utility that is obtained with its execution, with the goal of producing a high overall profit. Our analytical results show that the simple heuristic proposed achieves very high relative efficiency in the use of the hybrid infrastructure. We also demonstrate that the ability to estimate the grid behaviour is an important condition for making contracts that allow such relative efficiency values to be achieved. On the other hand, our simulation results with realistic error predictions show only a modest improvement in the profit achieved by the simple heuristic proposed, when compared to a heuristic that does not consider the grid when planning contracts, but uses it, and another that is completely oblivious to the existence of the grid. This calls for the development of more accurate predictors for the availability of P2P grids, and more elaborated heuristics that can better deal with the several sources of non-determinism present in this hybrid infrastructure.

Tramite un questionario strutturato e stata rilevata la preparazione ai disastri, la preoccupazione e la probabilitŕ di accadimento per un evento alluvionale, intervistando un campione di 407 persone residenti in 9 comuni della Valle del Lys (Valle d'Aosta). Le analisi descrittive mostrano una relazione diretta fra la valutazione della probabilitŕ di accadimento e la preoccupazione; fra quest'ultima e l'adozione di comportamenti preventivi e ulteriori relazioni con alcune caratteristiche socio-demografiche ed esperienziali degli intervistati. Le analisi multivariate, inoltre, evidenziano come la preparazione ai disastri sia positivamente associata alla preoccupazione, ma non alla valutazione della probabilitŕ di accadimento.

There is still limited knowledge about the interrelations among the age of initiation of different substances and the diverse aspects of adolescent functioning. The present cross-national study aimed at exploring the presence of a time-order pattern of age of initiation of different substances and the relationships with personal and relational resources and vulnerabilities, drawn from the problem behaviour theory by Jessor et al. (1991). The sample consisted of 970 adolescents from Italy and The Netherlands, of whom 198 were fully initiated in alcohol, first tobacco use, regular tobacco smoking and marijuana. In both countries, cumulative scale analyses showed the presence of a pattern of age of initiation in the different types of substances. The earlier the age of onset of one substance, the earlier the age of onset of the other substances. Furthermore, the higher the personal resources and the healthy, conventional parents and friend models, the older the age of initiation of different substances by both Dutch and Italian adolescents. With respect to the use of alcohol, the higher the relational resources, the older the age of initiation. Conversely, the higher the adolescents perceived relational vulnerabilities, the younger their age of initiation in drugs. These findings suggest that preventive interventions might be more successful when they are precocious, enhance personal capabilities, and produce changes in the adolescent life context.

English This study aims to investigate how affective states are described in the Old Testament. Three psychology researchers were asked to read the first five books of the first Italian version (from the 18th century) of the Old Testament (Pentateuch, or Torah) and to select all the terms that referred to an emotion or a feeling. For each selected term, they also had to pinpoint its position in the text (i.e. book, chapter) and the various characteristics of the affective episode in which it appeared (i.e. experiencing subject, situational antecedent, intentional object, instrumental behaviors). The textual analysis showed that the affective terms most frequently cited referred to four categories: “fear, awe”, “anger, hate”, “affliction, pain, sadness” and “love, joy, happiness”. These categories were significantly associated with specific instrumental behaviors and characters of the narration. Multivariate analysis also indicated that the frequency of citation of the affective categories varied significantly as a function of the book in which they appeared. In the conclusions, the authors discuss the conception of emotions and feelings issuing from the Pentateuch analysis. French L'article se propose d'analyser de quelle manière les expériences affectives sont décrites et évaluées dans la Bible. On a demandé à trois chercheurs psychologues de lire les cinq premiers livres de la première version italienne (du 18ème siècle) de la Bible (le Pentateuque, ou Torah) et d'y sélectionner tous les termes se référant à des expériences affectives (émotions et sentiments). Pour chaque terme sélectionné, ils devaient aussi indiquer sa position dans le texte (livre, chapitre) et les différentes composantes de l'épisode au cours duquel l'émotion ou le sentiment étaient expérimentés (le sujet qui expérimentait l'expérience affective, la situation qui la causait, l'objet intentionnel auquel elle se référait, le comportement réactif du sujet, l'évaluation morale de l'expérience). Les résultats de la sélection ont mis en évidence que les termes affectifs les plus fréquents se réfèrent à quatre catégories d'émotions, à savoir, dans l'ordre, la peur, la colère, la tristesse, la joie. Ces émotions sont expérimentées à des fréquences différentes par les principaux personnages de la narration (Dieu, les hommes, le Peuple d'Israël). L'émotion le plus souvent expérimentée par Dieu est la colère et par les différents personnages humains, la peur. Aucune évaluation morale négative quant aux expériences affectives n'émerge de l'analyse du texte. L'analyse multivariée met en évidence le fait que la fréquence des citations des catégories émotionnelles change sensiblement en fonction des cinq livres du Pentateuque. Dans leurs conclusions, les auteurs examinent la conception implicite des émotions et des sentiments qui semble émerger du Pentateuque.

Adolescent substance use is constantly high or increasing in Western countries. There is still limited knowledge about the interrelations between the different substances and the diverse aspects of adolescent functioning that may affect this phenomenon. The present cross-national study is aimed to explore the presence of a constellation of different substances and the relationships between substance use and personal and relational resources and vulner-abilities drawn from the problem behaviour theory by Jessor, Donovan, and Costa (1991). The sample consisted of 970 Italian and Dutch adolescents. In both countries, cumulative scale analyses showed the presence of a constellation among the different types of substances. Furthermore, the higher the personal resources and the more positive the models the lower the use of different substances by both Dutch and Italian adolescents. Conversely, the higher the relational vulnerabilities the higher also was the involvement in drugs. However, the explained variance...

We investigate the facial expression of emotions in very young congenitally blind children to ” nd out whether these are objectively and subjectively recognisable. We also try to see whether the adequacy of the facial expression of emotions changes as the children get older. We video recorded the facial expressions of 10 congenitally blind children and 10 sighted children (as a control group) in seven everyday situations considered as emotion elicitors. The recorded sequences were analysed according to the Maximally Discriminative Facial Movement Coding System (Max; Izard, 1979) and then judged by 280 decoders who used four scales (two dimensional and two categorical) for their answers. The results showed that all the subjects (both the blind and the sighted) were able to express their emotions facially, though not always according to the theoretically expected pattern. Recognition of the various expressions was fairly accurate, but some emotions were systematically confused with others. The decoders’ answers to the dimensional and categorical scales were similar for both blind and sighted subjects. Our ” ndings on objective and subjective judgements show that there was no decrease in the facial expressiveness of the blind children in the period of development considered.

Performance analysis and tuning is an important step in programming multicore- and manycore-based parallel architectures. While there are several tools to help developers analyze application performance, no tool provides recommendations about how to tune the code. The AutoTune project is extending Periscope, an automatic distributed performance analysis tool developed by Technische Universitat Munchen, with plugins for performance and energy efficiency tuning. The resulting Periscope Tuning Framework will be able to tune serial and parallel codes for multicore and manycore architectures and return tuning recommendations that can be integrated into the production version of the code. The whole tuning process --- both performance analysis and tuning --- will be performed automatically during a single run of the application.

Previous work produced a parallel and moderately scalable wavefront sensor model as part of a larger integrated telescope model. This relied on traditional high performance computing (HPC) techniques using optimised C and MPI based parallelism to marry maximum performance with the productive high-level modelling environment of MATLAB. In the intervening period the computational power and flexibility offered by graphics processors (GPUs) has increased dramatically. This presents both new options in terms of the level of hardware required to perform simulations and also new capabilities in terms of the scope of such simulations. We present a discussion of the currently available approaches and test case performance results based on a port to a GPU platform.

Peer-to-peer (P2P) desktop grids have been proposed as an economical way to increase the processing capabilities of information technology (IT) infrastructures. In a P2P grid, a peer donates its idle resources to the other peers in the system, and, in exchange, can use the idle resources of other peers when its processing demand surpasses its local computing capacity. Despite their cost-effectiveness, scheduling of processing demands on IT infrastructures that encompass P2P desktop grids is more difficult. At the root of this difficulty is the fact that the quality of the service provided by P2P desktop grids varies significantly over time. The research we report in this paper tackles the problem of estimating the quality of service of P2P desktop grids. We base our study on the OurGrid system, which implements an autonomous incentive mechanism based on reciprocity, called the Network of Favours (NoF). In this paper we propose a model for predicting the quality of service of a P2P desktop grid that uses the NoF incentive mechanism. The model proposed is able to estimate the amount of resources that is available for a peer in the system at future instants of time. We also evaluate the accuracy of the model by running simulation experiments fed with field data. Our results show that in the worst scenario the proposed model is able to predict how much of a given demand for resources a peer is going to obtain from the grid with a mean prediction error of only 7.2%.