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BACKGROUND: Model-Driven Engineering claims a positive impact on software productivity and satisfaction. However, few efforts have been made to collect evidences that assess its true benefits and limitations. OBJECTIVE: To compare the productivity and satisfaction of junior Web developers during the development of the business layer of a Web 2.0 Application when using either a code-centric, a model-based (UML) or a Model-Driven Engineering approach (OOH4RIA). RESEARCH METHOD: We designed a full factorial, intra-subject experiment in which 26 subjects, divided into five groups, were asked to develop the same three modules of a Web application, each one using a different method. We measured their productivity and satisfaction with each approach. RESULTS: The use of Model-Driven Engineering practices seems to significantly increase both productivity and satisfaction of junior Web developers, regardless of the particular application. However, modeling activities that are not accompanied by a strong generation environment make productivity and satisfaction decrease below code-centric practices. Further experimentation is needed to be able to generalize the results to a different population, different languages and tools, different domains and different application sizes.

Usability and accessibility are crucial factors in Web application development. The ease or difficulty that users experience with Web applications determines their success or failure. According to recent studies, an estimated 90 sites and applications suffer from usability and/or accessibility problems. As user satisfaction has increased in importance, the need for usable and accessible Web applications has become more critical. To achieve usability for a Web product (e.g., a service, a model, a running application, a portal), the attributes of Web artefacts must be clearly defined. Otherwise, assessment of usability is left to the intuition or to the responsibility of people who are in charge of the process. In this sense, quality models (describing all the usability sub-characteristics, attributes and their relationships) should be built, and usability evaluation methods should be used during the requirements, design and implementation stages based on these models. Similarly, identifying the set of characteristics that make the Web more accessible for everybody, including those with disabilities, is necessary to systematize the way practitioners deal with accessibility issues.

In the last years, the need for a sound integration of the requirements engineeringdiscipline with the model driven developmentparadigm has promoted the definition of a myriad of requirements metamodels. However, most existing proposals still lack backward (alignment with business goals) or forward (connection with validation methods such as measures) traceability, which hampers their usefulness. In this paper, we present a `measurable requirements metamodel' that connects goals, requirements, and measures, thus fostering a goal-oriented measurable requirements engineeringperspective. In order to provide this metamodel with a familiar notation, we also present a UML profile based on the i* framework, which facilitates its adoption in the context of any UML-based software engineering process.

According to recent studies, an estimated 90% of Web sites and applications suffer from usability and/or accessibility problems. As user satisfaction has increased in importance, the need for usable and accessible Web applications has become more critical. To achieve usability for a Web product (e.g., a service, a model, a running application, a portal), the attributes of Web artefacts must be clearly defined. Otherwise, assessment of usability is left to the intuition or to the responsibility of people who are in charge of the process. In this sense, usability models (describing all the usability sub-characteristics, attributes and their relationships) should be built, and Usability Evaluation Methods (UEMs) should be used during the requirements, design and implementation stages based on these models. Similarly, identifying the set of characteristics that make the Web more accessible for everybody, including those with disabilities is necessary to systematize the way practitioners face accessibility issues.

WE practices lack an impact on industry, partly due to a WE field that is not quality-aware. In fact, it is difficult to find WE methodologies that pay explicit attention to quality aspects. However, the use of a systematic process that includes quality concerns from the earliest stages of development can contribute to easing the building up of quality-guaranteed Web applications without drastically increasing development costs and time-to-market. In this kind of process, quality issues should be taken into account while developing each outgoing artifact, from the requirements model to the final application. Also, quality models should be defined to evaluate the quality of intermediate WE artifacts and how it contributes to improving the quality of the deployed application. In order to tackle its construction while avoiding some of the most common problems that existing quality models suffer from, in this paper we propose a number of WE quality models to address the idiosyncrasies of the different stakeholders and WE software artifacts involved. Additionally, we propose that these WE quality models are supported by an ontology-based WE measurement meta-model that provides a set of concepts with clear semantics and relationships. This WE Quality Metamodel is one of the main contributions of this paper. Furthermore, we provide an example that illustrates how such a metamodel may drive the definition of a particular WE quality model.

Navigability is a main concern in the design of Web applications. In order to assess such navigability a number of measures has been proposed. From them, measures defined on conceptual models are specially relevant, as it is well known that high quality conceptual models are critical to the success of the deployed system. However, measurement methods associated to such measures, as well as the design modifications that need to be performed on the models in order to improve their values, are usually tightly coupled with particular Web Engineering approaches. This fact compromises their effectiveness and their propagation capacity to different environments and/or methodologies. Our aim in this paper is to illustrate how navigability measures can be captured in a general manner. In this way, not only is it possible to define a reusable set of relevant measures for a given family of applications, but also such measures can be queried in the context of MDA transformation rules. These rules capture both the measure decision criteria and the design modifications that should take place if the measure value for a given navigational model does not match such criteria.

The continuous advances in Web technologies are posing new challenges to Web Engineering proposals, which now require the inclusion Software Architecture techniques in order to integrate the explicit consideration of non-functional features in the Web application design process. In this article we propose a new approach called WebSA, based on the the MDA (Model Driven Architecture) paradigm. WebSA specifies a model driven process that adds to the traditional Web-related functional viewpoint a new software architectural viewpoint that permits, by means of successive model transformations, to establish the desired target application structure.

This article presents an extension of the OO-H conceptual modelling approach to address the particulars associated with the design and specification of dynamic personalization. We describe how conventional navigation and presentation diagrams are influenced by personalization properties. The main benefit is that personalization specification can be modified without recompile the rest of the application modules.

Database prototyping is a technique widely used both to validate user requirements and to verify certain application functionality. These tasks usually require the population of the underlying data structures with sampling data that, additionally, may need to stick to certain restrictions. Although some existing approaches have already automated this population task by means of random data generation, the lack of semantic meaning of the resulting structures may interfere both in the user validation and in the designer verification task.In order to solve this problem and improve the intuitiveness of the resulting prototypes, this paper presents a population system that, departing from the information contained in a UML-compliant Domain Conceptual Model, applies Information Extraction techniques to compile meaningful information sets from texts available through Internet. The system is based on the semantic information extracted from the EWN lexical resource and includes, among other features, a named entity recognition system and an ontology that speed up the prototyping process and improve the quality of the sampling data.

The application of conceptual models that assure both the consistency and usability of Electronic Product Catalogs (EPC's) is a main concern in the e-commerce community, mainly due to the impact a correct design of such interfaces has on the final e-store sales figures. This article describes how the OO-H Method web-interface modeling approach can be successfully applied to the design of Business to Consumer (B2C) application interfaces. In order to address the specific domain semantics, OO-H Method adds a new concept called 'dimension attribute', which is extracted from the datawarehouse field, and defines a comparison function applicable to these attributes. Also, a set of e-commerce Interface Usability Patterns that address some design problems likely to appear on the different store components and a materialization strategy are introduced to complete our proposal. The use of patterns to capture the semantics specifically related to e-commerce applications, and to manage the knowledge captured in the catalog structure, guarantees the reuse of techniques coming from different fields and proven useful for the increment of sales on internet.

Object-oriented conceptual modeling approaches must be reconsidered in order to address the particulars associated with the design of web application interfaces. In this context, the paper introduces the presentation layer of OO-HMethod, an extension of the OO-Method conceptual modeling approach that is devoted to the specification of this kind of interfaces. The OO-H Method presentation approach is based on the concept of templates. Each page template may fall into one among a set of categories, which together cover the different presentation perspectives captured in the model. In order to better define the page template structure, a new diagram is introduced: the Abstract Presentation Diagram (APD). The APD does not need to be drawn from scratch: the navigation structure previously defined in the OO-HMethod Navigation Access Diagram (NAD) provides the information needed to automatically generate a default APD. This skeleton template structure may be further refined and enriched with the aid of the OO-HMethod Interface Pattern Catalog. As a result, a web application interface is generated in an automated way.