A Full Probabilistic Model for Yes/No Type Crowdsourcing in Multi-Class Classification

Crowdsourcing has become widely used in supervised scenarios where training sets are scarce and difficult to obtain. Most crowdsourcing models in the literature assume labelers can provide answers to full questions. In classification contexts, full questions require a labeler to discern among all possible classes. Unfortunately, discernment is not always easy in realistic scenarios. Labelers may not be experts in differentiating all classes. In this work, we provide a full probabilistic model for a shorter type of queries. Our shorter queries only require "yes" or "no" responses. Our model estimates a joint posterior distribution of matrices related to labelers' confusions and the posterior probability of the class of every object. We developed an approximate inference approach, using Monte Carlo Sampling and Black Box Variational Inference, which provides the derivation of the necessary gradients. We built two realistic crowdsourcing scenarios to test our model. The first scenario queries for irregular astronomical time-series. The second scenario relies on the image classification of animals. We achieved results that are comparable with those of full query crowdsourcing. Furthermore, we show that modeling labelers' failures plays an important role in estimating true classes. Finally, we provide the community with two real datasets obtained from our crowdsourcing experiments. All our code is publicly available.Comment: SIAM International Conference on Data Mining (SDM19), 9 official pages, 5 supplementary page

Evaluacion de las propiedades fisicas y mecanicas de la madera de olivillo (Aetoxicon puctatum) de la Region del Maule

83 p.El siguiente estudio consiste en la evaluación de las propiedades físicas y mecánicas de la madera nativa de olivillo proveniente de tres sectores de la región del Maule, Molina, Empedrado y Linares. Con el objetivo de entregar mayor información y complementar la ya existente en fomento de una especie nativa de la región, para una mejor utilización de esta madera. En las propiedades físicas son analizados la densidad, contracción radial y tangencial y el contenido de humedad. De cada sector son distintos los diámetros y cantidad de anillos de crecimiento, obteniendo 36 probetas en total, 12 por sector.Las propiedades mecánicas a estudiar son dureza con 21 probetas, compresión paralela y perpendicular, con 36 y 18 probetas respectivamente y flexión 18 probetas. El número de probetas en este caso resultó ser variable debido a las características del material. Los ensayos fueron realizados en el Laboratorio del Centro Tecnológico del Álamo en la Universidad de Talca. Las trozas provenientes de los tres sectores son procesadas en el Centro Regional de Tecnología en Industrias de la Madera (CERTIM) ubicado en la Universidad de Talca hasta obtener las probetas. Los pasos a seguir para la realización de los ensayos se encuentran en las normas chilenas por lo que las probetas deben estar acondicionadas a un contenido de humedad del 12%. Debido a esto se secan las probetas a una temperatura muy baja y se llevan a cámara de clima por algún tiempo. A traves de un análisis descriptivo se analizan las propiedades físicas y mecánicas y con análisis estadistico las físicas y una mecánica correspondiente a compresión paralela.Los análisis estadísticos demuestran que no existe diferencia significativa entre los distintos sectores. Las propiedades resultan similares a lo que dice la referencia, clasificándola como una madera densidad media, de clase mediana que puede ser utilizada para muebles, revestimientos y tableros./ SUMMARY: The following study is the evaluation of the physical and mechanical properties of wood of native olivillo from three areas of the Maule region, Molina Linares and Empedrado. With the main purpuse to give and to complement the information already existing of the a native species in order to make it more valueble for a better use of the wood. In the physical properties the density, radial contraccion and tangencial and moisture content are analyzed. Of sector the diameters are different and tha number of growing rings, giving a total of 36 samples, 12 per sector. The mechanical properties to study are hardness with 21 samples, compression parallel and perpendicular, with 36 and 18 samples respectively and flexibility 18 samples. The number of samples in this case turned out to be variable due to the characteristics of the material. The trials were carried out in the Laboratory of the Alamo Technological Center in the Universidad de Talca. The logs coming from the three sectors are processed in the Centro Regional de Tecnología en Industrias de la Madera (CERTIM) located in the Universidad de Talca until obtaining the samples. The steps to follow for the execution of the trials are found in the chilenas norms for which the samples should be conditioned to a content of humidity of the 12%. Due to this the samples are dried to a very low temperature and they are taken to a camera of climate for a period. The physical and mechanical properties a descriptive analysis are analyzed and with a statistical analysis the physical and mechanical parallelcompression properties. The statistical the analyzes brove that does not exist significant differences among the different sectors. The properties turn out to be similar to what the reference says, classifying it as an average density wood, of medium class that can be used for furniture, coverings and panel

Analyzing the institutional challenges for the agricultural (re)use of wastewater in developing countries

Wastewater reuse has great potential to reduce pressure on water resources, especially for the agricultural sector. At the same time, wastewater reuse needs to be addressed because of the risks it represents for public health and the environment. As water becomes scarce in many regions around the world and informal use of wastewater for irrigation propagates particularly in developing countries, it is important to reconsider wastewater reuse within the broader concept of water resources management. However, water resources management and wastewater management in particular are complex and challenging because water problems are heterogeneous and variable over time and space. Solutions to water problems will depend not only on water availability, but on a range of other factors that influence the water sector such as the institutional capacity, legal and regulatory frameworks, sociopolitical and environmental conditions, educational and development conditions, financial resources, technology, attitudes and perceptions, and modes of governance including issues like political interference, transparency and corruption. Given this complexity, the need to unravel the institutional dimensions of wastewater reuse, in order to understand the challenges for its formalization becomes evident. In the light of this challenge, the objective of this research is to provide understanding on the incentives and drivers for a (step-wise) change of the institutional settings, moving wastewater reuse in agriculture from its informal status towards a formal, safe and productive use. This is done by comparing countries with different governance structures along a trajectory towards formalization

A Industrialização e o m ercado de trabalho brasileiro perante reestruturação produtiva.

TCC (graduação)- Universidade Federal de Santa Catarina,Centro Sócio-Econômico, Curso de Ciências Econômicas.Este trabalho é a sistematização pedagógica e científica resultante da realização do curso de Graduação em Ciências Econômicas. Tem por objetivo principal analisar as relações ocorridas no mercado de trabalho, entre trabalhadores e empresas, bem como contextualizar essas relações no atual processo de Reestruturação Produtiva. A pesquisa procura analisar as relações trabalhistas entre trabalhadores e empresas no Brasil, apontando o contexto histórico e as características pertinentes para compreensão da estrutura atual do mercado de trabalho. A metodologia baseia-se em uma pesquisa exploratória e qualitativa, de caráter documental. Ao concluir o trabalho observou-se a importância das instituições representativas após a inserção brasileira no contexto de reestruturação produtiva na década de noventa

Deliberate self-harm in a clinical sample: the impact of schema modes, parental bonding and perceived stress

Introduction: Deliberate self-harm is being increasingly recognised as a behaviour with significant clinical importance. Yet, there remains uncertainty regarding which forms of psychological therapy are most effective for its treatment. Schema Therapy is an integrative psychotherapy blending elements of cognitive behaviour therapy, object relations and gestalt therapy into a unified approach for the treatment of individuals with complex and chronic psychological conditions. The current thesis aimed to provide a better understanding of the Schema Therapy model and its association with deliberate self-harm. Systematic Review: Despite the increasing evidence base for the efficacy of Schema Therapy, less is known about the evidence for its theoretical underpinnings. To address this gap in the literature a systematic review was undertaken to explore the following question: How empirically supported is the theoretical underpinning of Schema Therapy? In a systematic search of the literature conducted until 01 June 2012, studies based on cross-sectional, longitudinal, intervention, meditational and experimental designs were considered. These studies underwent detailed quality analysis culminating in 19 articles being included in the current review. Overall these studies indicate that many of the key theoretical assumptions in Schema Therapy are supported by the literature. Empirical Study: Schema Therapy has recently been expanded to include the ‘schema mode’ concept, with a number of researchers highlighting an association between particular schema modes and a number of chronic psychological conditions. Although the schema mode model allows a method for understanding moment-to-moment emotional states it has not previously been explored in relation to deliberate self-harm. The current project aimed to explore the relationship between these variables and their association with early experiences of parental bonding and current levels of perceived stress. 70 psychiatric outpatients with a history of deliberate self-harm completed a number of measures including the Deliberate Self-Harm Inventory, Schema Mode Inventory, Parental Bonding Instrument and Perceived Stress Scale. Results revealed significant associations between deliberate self-harm, maladaptive schema modes, perceived stress and patterns of parental care. Maladaptive schema modes significantly mediated the relationship between parental care and deliberate self-harm. The Punitive Parent and Angry Child modes were significant mediators in this relationship. Conclusion: Results from the systematic review support the notion that Schema Therapy has a good theoretical underpinning. The empirical study also supports Schema Therapy by highlighting the meditational role of maladaptive schema modes in the relationship between low parental care in childhood and deliberate self-harm in adulthood. These findings provide further support for the Schema Therapy model and suggest that individuals with deliberate self-harm may benefit from this treatment

A Phenomenological Case Study of Pakistani Science Teachers’ Experiences of Professional Development

Effective teacher development is significant for any educational system to remain competitive in the global arena (Bayar, 2014). However, science teachers’ professional development activities have often been found to be ineffective (Opfer & Pedder, 2011). Science teachers also minimally participate in such activities due to their ineffective experiences (Chval, Abell, Pareja, Musikul & Ritzka, 2007). Understanding how science teachers’ experiences are constructed is also crucial to create programs to meet their needs (Schneider & Plasman, 2011). It is essential in the construction of professional development experiences to recognize who is being served in professional development (Saka, 2013). But rigorous methods are required to understand the outcomes of professional development (Koomen, Blair, Young-Isebrand & Oberhauser, 2014). The purpose of this phenomenological case study was to study how secondary school science teachers describe their lived experiences of professional development in Punjab (Pakistan). How do these teachers understand, make sense, and use of those intended goals of professional development opportunities and change their practices through the implementation of learned knowledge of professional development? This study used purposive sampling to collect the qualitative data from fifteen secondary school science teachers of Punjab (Pakistan). The data collection was done through conducting semi-structured in-depth phenomenological interviews with these science teachers (Seidman, 2013). The data were analyzed using three-stage coding methods, and thematic analysis. Three main themes emerged from the analysis of data. The first theme of sense making is about their understanding and description of intended meaning of professional development activities. The second theme of meaningful experiences captured the participants perceived benefits from the PD activities. The third theme of contextual and cultural factors is focused on the understanding the impact of these factors in imparting of professional development experiences. The findings of the study communicate the significance of science teachers’ role in professional development activities. Science teachers’ voices, needs and active involvement must be taken into consideration in the designing and implementation of such activities