Damm, Hans (1857 - )

This biographical summary was created by the Works Progress Administration (WPA) between 1936 and 1939

Why and how selection patterns in classroom networks differ between students : the potential influence of networks size preferences, level of information, and group membership

Los estudiantes de secundaria pueden escoger compañeros como nuevos amigos utilizando un repertorio de modalidades. Pueden querer activamente crear nuevas amistades, utilizar la estructura existente de la red y/o utilizar la información, escasa y a menudo errónea, sobre los "candidatos". En este artículo teórico argumentamos que dichas modalidades de selección no deben ser estudiadas como resultado de reglas generales tal y como se viene haciendo en los estudios sobre redes sociales. En concreto, afirmamos que las preferencias relativas al tamaño de las redes, el nivel de información sobre los atributos de los compañeros de clase y la pertenencia a grupos pueden ser distintas para cada alumno y, por ello, también sus modalidalidades de selección pueden ser distintas. En este artíclo se esbozan las articulaciones teóricas entre ellos.High school students can select class mates for new friendships using a repertoire of patterns. They can actively pursue new friendships, make use of the existing network structure, and/ or use the scarce and often erroneous information about candidates. In this theoretical paper, we argue that such selection patterns should not be studied as the result of general rules, as is usually done in social network studies. Specifically, we state that network size preferences, the level of information about individual attributes of fellow classmates, and group membership are likely to differ among high school students, and that as a result, also their selection patterns are likely to be different. In this paper we sketch the theoretical articulations between these

Cómo y por qué los modelos de selección difieren entre estudiantes. La influencia potencial de los tamaños de la red, el nivel de información y la pertenencia a grupos

High school students can select class mates for new friendships using a repertoire of patterns. They can actively pursue new friendships, make use of the existing network structure, and/ or use the scarce and often erroneous information about candidates. In this theoretical paper, we argue that such selection patterns should not be studied as the result of general rules, as is usually done in social network studies. Specifically, we state that network size preferences, the level of information about individual attributes of fellow classmates, and group membership are likely to differ among high school students, and that as a result, also their selection patterns are likely to be different. In this paper we sketch the theoretical articulations between these.Los estudiantes de secundaria pueden escoger compañeros como nuevos amigos utilizando un repertorio de modalidades. Pueden querer activamente crear nuevas amistades, utilizar la estructura existente de la red y/o utilizar la información, escasa y a menudo errónea, sobre los “candidatos”. En este artículo teórico argumentamos que dichas modalidades de selección no deben ser estudiadas como resultado de reglas generales tal y como se viene haciendo en los estudios sobre redes sociales. En concreto, afirmamos que las preferencias relativas al tamaño de las redes, el nivel de información sobre los atributos de los compañeros de clase y la pertenencia a grupos pueden ser distintas para cada alumno y, por ello, también sus modalidalidades de selección pueden ser distintas. En este artíclo se esbozan las articulaciones teóricas entre ellos

"How May I Help You?": Modeling Twitter Customer Service Conversations Using Fine-Grained Dialogue Acts

Given the increasing popularity of customer service dialogue on Twitter, analysis of conversation data is essential to understand trends in customer and agent behavior for the purpose of automating customer service interactions. In this work, we develop a novel taxonomy of fine-grained "dialogue acts" frequently observed in customer service, showcasing acts that are more suited to the domain than the more generic existing taxonomies. Using a sequential SVM-HMM model, we model conversation flow, predicting the dialogue act of a given turn in real-time. We characterize differences between customer and agent behavior in Twitter customer service conversations, and investigate the effect of testing our system on different customer service industries. Finally, we use a data-driven approach to predict important conversation outcomes: customer satisfaction, customer frustration, and overall problem resolution. We show that the type and location of certain dialogue acts in a conversation have a significant effect on the probability of desirable and undesirable outcomes, and present actionable rules based on our findings. The patterns and rules we derive can be used as guidelines for outcome-driven automated customer service platforms.Comment: 13 pages, 6 figures, IUI 201

Approximate modelling of the multi-dimensional learner

This paper describes the design of the learner modelling component of the LeActiveMath system, which was conceived to integrate modelling of learners' competencies in a subject domain, motivational and affective dispositions and meta-cognition. This goal has been achieved by organising learner models as stacks, with the subject domain as ground layer and competency, motivation, affect and meta-cognition as upper layers. A concept map per layer defines each layer's elements and internal structure, and beliefs are associated to the applications of elements in upper-layers to elements in lower-layers. Beliefs are represented using belief functions and organised in a network constructed as the composition of all layers' concept maps, which is used for propagation of evidence

Reduced somatostatin signalling leads to hypersecretion of glucagon in mice fed a high-fat diet

Objectives:&nbsp;Elevated plasma glucagon is an early symptom of diabetes, occurring in subjects with impaired glucose regulation. Here, we explored alpha-cell function in female mice fed a high-fat diet (HFD)&mdash;a widely used mouse model of prediabetes. Methods:&nbsp;We fed female mice expressing the Ca2+&nbsp;indicator GCaMP3 specifically in alpha-cells an HFD or control (CTL) diet. We then conducted&nbsp;in&nbsp;vivo&nbsp;phenotyping of these mice, as well as experiments on isolated (ex&nbsp;vivo) islets and in the&nbsp;in situ&nbsp;perfused pancreas. Results:&nbsp;In&nbsp;vivo,&nbsp;HFD-fed mice exhibited increased fed plasma glucagon levels and a reduced response to elevations in plasma glucose. Glucagon secretion from isolated islets and in the perfused mouse pancreas was elevated under both hypo- and hyperglycaemic conditions. In mice fed a CTL diet, increasing glucose reduced intracellular Ca2+&nbsp;([Ca2+]i) (oscillation frequency and amplitude). This effect was also observed in HFD mice; however, both the frequency and amplitude of the [Ca2+]i&nbsp;oscillations were higher than those in CTL alpha-cells. Given that alpha-cells are under strong paracrine control from neighbouring somatostatin-secreting delta-cells, we hypothesised that this elevation of alpha-cell output was due to a lack of somatostatin (SST) secretion. Indeed, SST secretion in isolated islets from HFD mice was reduced but exogenous SST also failed to suppress glucagon secretion and [Ca2+]i&nbsp;activity from HFD alpha-cells, in contrast to observations in CTL mice. Conclusions:&nbsp;These findings suggest that reduced delta-cell function, combined with intrinsic changes in alpha-cell sensitivity to somatostatin, accounts for the hyperglucagonaemia in mice fed an HFD.</p