Going beyond simple sample size calculations: a practitioner's guide

Basic methods to compute required sample sizes are well understood and supported by widely available software. However, the sophistication of the methods commonly used has not kept pace with the complexity of commonly employed experimental designs. We compile available methods for sample size calculations for continuous and binary outcomes with and without covariates, for both clustered and non-clustered RCTs. Formulae for both panel data and unbalanced designs are provided. Extensions include methods to: (1) optimise the sample when costs constraints are binding, (2) compute the power of a complex design by simulation, and (3) adjust calculations for multiple testing

Examining Teaching Practices that Increase Student Mathematical Achievement

The current data in the United States surrounding mathematics shows that there are issues that must be addressed with teaching and learning math in the K-12 setting. In the perfect world, all students would meet grade level expectations in math prior to moving to another grade; however, this is not what is taking place. Students are not meeting proficiency, and as a result teachers and students alike are not gaining confidence in teaching/learning mathematics. This project looks at the Math Workshop Model as being one alternative to the more traditional teaching practices that are used today in the ABC School District. Through a review of literature, this project identifies four components of an effective Math Workshop Model, specifically geared for elementary aged students. Furthermore, a continuous professional development plan is established with resources such as surveys, data tracking spreadsheets, formative assessments, a slideshow presentation, professional development calendars/outlooks, and documents that support the implementation of the Math Workshop Model

Evolution of ecosystems for Language-Driven Engineering

Language-Driven Engineering (LDE) is a means to model-driven software development by creating Integrated Modeling Environments (IMEs) with Domain/Purpose-Specific Languages (PSLs), each tailored towards a specific aspect of the respective system to be modeled, thereby taking the specific needs of developers and other stakeholders into account. Combined with the powerful potential of full code generation, these IMEs can generate complete executable software applications from descriptive models. As these products themselves may again be IMEs, this approach leads to LDE Ecosystems of modeling environments with meta-level dependencies. This thesis describes new challenges emerging from changes that affect single components, multiple parts or even the whole LDE ecosystem. From a top-down perspective, this thesis discusses the necessary support by language definition technology to ensure that corresponding IMEs can be validated, generated and tested on demand. From a bottom-up perspective, the formulation of change requests, their upwards propagation and generalization is presented. Finally, the imposed cross-project knowledge sharing and transfer is motivated, fostering interdisciplinary teamwork and cooperation. Based on multifaceted contributions to full-blown projects on different meta-levels of an exemplary LDE ecosystem, this thesis presents specific challenges in creating and continuously evolving LDE ecosystems and deduces a concept of PUTD effects to systematically address various dynamics and appropriate actions to manage both product-level requests that propagate upwards in the meta-level hierarchy as well as the downward propagation of changes to ensure product quality and adequate migration of modeled artifacts along the dependency paths. Finally, the effect of language-driven modeling on the increasingly blurred line between building and using software applications is illustrated to emphasize that the distinction between programming and modeling becomes a mere matter of perspective

EUD-MARS: End-User Development of Model-Driven Adaptive Robotics Software Systems

Empowering end-users to program robots is becoming more significant. Introducing software engineering principles into end-user programming could improve the quality of the developed software applications. For example, model-driven development improves technology independence and adaptive systems act upon changes in their context of use. However, end-users need to apply such principles in a non-daunting manner and without incurring a steep learning curve. This paper presents EUD-MARS that aims to provide end-users with a simple approach for developing model-driven adaptive robotics software. End-users include people like hobbyists and students who are not professional programmers but are interested in programming robots. EUD-MARS supports robots like hobby drones and educational humanoids that are available for end-users. It offers a tool for software developers and another one for end-users. We evaluated EUD-MARS from three perspectives. First, we used EUD-MARS to program different types of robots and assessed its visual programming language against existing design principles. Second, we asked software developers to use EUD-MARS to configure robots and obtained their feedback on strengths and points for improvement. Third, we observed how end-users explain and develop EUD-MARS programs, and obtained their feedback mainly on understandability, ease of programming, and desirability. These evaluations yielded positive indications of EUD-MARS

Harvesting models from web 2.0 databases

International audienceData rather than functionality are the sources of competitive advantage for Web2.0 applications such as wikis, blogs and social networking websites. This valuable information might need to be capitalized by third-party applications or be subject to migration or data analysis. Model-Driven Engineering (MDE) can be used for these purposes. However, MDE first requires obtaining models from the wiki/blog/website database (a.k.a. model harvesting). This can be achieved through SQL scripts embedded in a program. However, this approach leads to laborious code that exposes the iterations and table joins that serve to build the model. By contrast, a Domain-Specific Language (DSL) can hide these "how" concerns, leaving the designer to focus on the "what", i.e. the mapping of database schemas to model classes. This paper introduces Schemol, a DSL tailored for extracting models out of databases which considers Web2.0 specifics. Web2.0 applications are often built on top of general frameworks (a.k.a. engines) that set the database schema (e.g.,MediaWiki, Blojsom). Hence, table names offer little help in automating the extraction process. In addition, Web2.0 data tend to be annotated. User-provided data (e.g., wiki articles, blog entries) might contain semantic markups which provide helpful hints for model extraction. Unfortunately, these data end up being stored as opaque strings. Therefore, there exists a considerable conceptual gap between the source database and the target metamodel. Schemol offers extractive functions and view-like mechanisms to confront these issues. Examples using Blojsom as the blog engine are available for download

Achieving non-intrusive interoperability between models for involving users in modeling tasks

[EN] Model-Driven Development (MDD) promotes models as the cornerstone in the software development process, thereby displacing source code as the development process's main feature. Although this model-centric schema claims advantages over traditional software development (e.g., the code could be automatically generated from the models), it does not have the level of adoption that has been expected. The literature review reveals a broad agreement in the fact that end-users may develop and adapt systems themselves but the complexity in modeling standards and the lack of modeling skills prevents their active involvement in modeling tasks of existing MDD processes. To overcome this, end-users should be provided with different modeling languages that use concepts, which fit their particular skills, context and needs. This challenge is the main goal of this thesis, which is addressed by combining the End-user Development and the Model-Driven Development fields. This work starts with the involvement of end-users into the modeling tasks using a tool-supported visual modeling language that allows end-users to select and customize system features of pervasive systems using closer concepts for them. Afterwards, this thesis shows the necessity of enriching existing MDD processes for supporting the development of a new generation of software systems (e.g., smart health) that require expertise in a variety of domains. Consequently, different types of users (e.g., scientists, engineers and end-users) must actively participate in the description of model fragments that depend on their expertise using a different modeling language. Thus, users are able to collaborate to obtain a unified system description. At this point, it becomes necessary to provide mechanisms that transforms models fragments from one modeling language to another, delimits which model fragments are described by a different user, and integrates those model fragments. To provide this, the presented approach encompasses variability management in a novel way to enable collaborative modeling by supporting both the selection of model fragments of the system that may be described using a different modeling language, and the integration of those model fragments once they are described. Furthermore, interoperability mechanisms bridge two different modeling languages in a non-intrusive way with the structure of models by transforming the description of gaps. Thus, our proposal could enrich models of existing MDD processes with model fragments that have been described using a different modeling language, which could make users feel confident to adopt models for describing domain-specific content and could help to adopt MDD processes. The proposal has been validated in three case studies from different levels of complexity and domains: smart home systems, web information systems, and biomechanical protocols. The results have proven the applicability and feasibility of our approach to actively involve different types of users (end- users with software professionals, domain experts with software development experts, and doctors with biomedical engineers, respectively) in model descriptions of existing MDD processes using a different modeling language.[ES] En el Desarrollo de Software Dirigido por Modelos (DSDM) los modelos son la piedra angular del proceso de desarrollo de software, desplazando así al código fuente como artefacto principal. Aunque este enfoque centrado en modelos ofrece ventajas sobre el desarrollo de software tradicional (por ejemplo, la generación de código de forma automática a partir de los modelos) no tiene el nivel de adopción esperado. La literatura científica revela un amplio acuerdo en el hecho de que los usuarios finales puedan ellos mismos desarrollar y adaptar los sistemas pero la complejidad de los estándares de modelado y la carencia de habilidades de modelado impide su participación activa en procesos DSDM existentes. Para lograrlo, los usuarios finales deben disponer de lenguajes de modelado diferentes con conceptos adaptados a sus habilidades, contexto y necesidades. Este desafío es el objetivo principal de esta tesis que se aborda combinando las ideas del desarrollo orientado al usuario final y el DSDM. Este trabajo comienza involucrando usuarios finales en tareas de modelado con una herramienta que les proporciona un lenguaje de modelado visual para seleccionar y personalizar características de un sistema pervasivo utilizando conceptos familiares para ellos. Después, esta tesis motiva la necesidad de enriquecer procesos de DSDM existentes para soportar el desarrollo de una nueva generación de sistemas software (por ejemplo, salud inteligente) que requieren conocimientos especializados en una variedad de dominios. Consecuentemente, diferentes tipos de usuarios (por ejemplo, científicos, ingenieros y usuarios finales) deben participar activamente en la descripción de fragmentos de modelos que dependen de su experiencia utilizando un lenguaje de modelado diferente. De este modo, los usuarios pueden colaborar para obtener una descripción del sistema unificada. En este punto, es necesario proporcionar mecanismos que transformen e integren los fragmentos de un lenguaje de modelado a otro y delimiten qué fragmentos se describen por un usuario diferente. Para proporcionar esto, la propuesta presentada utiliza la gestión de variabilidad de forma novedosa para permitir modelado colaborativo seleccionando fragmentos de un modelo del sistema que pueden ser descritos utilizando un lenguaje de modelado diferente y, la integración de esos fragmentos una vez que hayan sido descritos. Además, la propuesta utiliza mecanismos de interoperabilidad para conectar dos lenguajes de modelado diferentes transformando la descripción de los fragmentos de una manera no invasiva con su estructura. Por tanto, nuestra propuesta puede enriquecer los modelos de procesos DSDM existentes con fragmentos de modelos que han sido descritos con un lenguaje diferente y esto, podría hacer que los usuarios se sientan seguros al adoptar modelos para describir contenido de dominio específico y podría ayudar a adoptar procesos DSDM. La propuesta ha sido validada en tres casos de estudio con diferentes niveles de complejidad y dominios: sistemas para el hogar inteligente, sistemas de información web y protocolos biomecánicos. Los resultados han demostrado la aplicabilidad y viabilidad de nuestra propuesta para involucrar diferentes tipos de usuarios (usuarios finales con profesionales de software, expertos en el dominio con expertos en desarrollo de software y, médicos con ingenieros biomédicos, respectivamente) en descripciones de modelos de procesos DSDM existentes utilizando un lenguaje de modelado diferente.[CA] En el Desenvolupament de Programari Dirigit per Models (DPDM) els models són la pedra angular del procés de desenvolupament de programari, desplaçant així al codi font com a artefacte principal. Encara que aquest enfocament centrat en models ofereix avantatges sobre el desenvolupament de programari tradicional (per exemple, la generació de codi de forma automàtica a partir dels models) no té el nivell d'adopció esperat. La literatura científica revela un ampli acord en el fet que els usuaris finals puguen ells mateixos desenvolupar i adaptar els sistemes però la complexitat dels estàndards de modelatge i la falta d'habilitats de modelatge impedeix la seua participació activa en processos DPDM existents. Per a aconseguir-ho, els usuaris finals han de disposar de llenguatges de modelatge diferents amb conceptes adaptats a les seues habilitats, context i necessitats. Aquest desafiament és l'objectiu principal d'aquesta tesi que s'aborda combinant les idees del desenvolupament orientat a l'usuari final i el DPDM. Aquest treball comença involucrant usuaris finals en tasques de modelatge amb una eina que els proporciona un llenguatge de modelatge visual que permet als usuaris finals seleccionar i personalitzar característiques d'un sistema pervasiu utilitzant conceptes familiars per a ells. Després, aquesta tesi motiva la necessitat d'enriquir processos de DPDM existents per a suportar el desenvolupament d'una nova generació de sistemes programari (per exemple, salut intel¿ligent) que requereixen coneixements especialitzats en una varietat de dominis. Conseqüentment, diferents tipus d'usuaris (per exemple, científics, enginyers i usuaris finals) han de participar activament en la descripció de fragments de models que depenen de la seua experiència utilitzant un llenguatge de modelatge diferent. D'aquesta manera, els usuaris poden col¿laborar per a obtenir una descripció del sistema unificada. En aquest punt, és necessari proporcionar mecanismes que transformen i integren els fragments d'un llenguatge de modelatge a un altre i delimiten quins fragments es descriuen per un usuari diferent. Per a proporcionar açò, la proposta presentada utilitza la gestió de variabilitat de forma nova per a permetre modelatge col.laboratiu seleccionant fragments d'un model del sistema que poden ser descrits utilitzant un llenguatge de modelatge diferent i, la integració d'aqueixos fragments una vegada que hagen sigut descrits. A més, la proposta utilitza mecanismes d'interoperabilitat per a connectar dos llenguatges de modelatge diferents transformant la descripció dels fragments d'una manera no invasiva amb la seua estructura. Per tant, la nostra proposta pot enriquir els models de processos DPDM existents amb fragments de models que han sigut descrits amb un llenguatge diferent i açò, podria fer que els usuaris se senten segurs en adoptar models per a descriure contingut de domini específic i podria ajudar a adoptar processos DPDM. La proposta ha sigut validada en tres casos d'estudi amb diferents nivells de complexitat i dominis: sistemes per a la llar intel¿ligent, sistemes d'informació web i protocols biomecànics. Els resultats han demostrat l'aplicabilitat i viabilitat de la nostra proposta per a involucrar diferents tipus d'usuaris (usuaris finals amb professionals de programari, experts en el domini amb experts en desenvolupament de programari i, metges amb enginyers biomèdics, respectivament) en descripcions de models de processos DPDM existents utilitzant un llenguatge de modelatge diferent.Pérez Pérez, MF. (2015). Achieving non-intrusive interoperability between models for involving users in modeling tasks [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/58429TESI