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The objective of this chapter is three-fold. First, it provides an overview of differences between Web and software development with respect to their development processes, technologies, quality factors, and measures. Second, it provides definitions for terms used throughout the book. Third, it discusses the need for empirical investigations in Web engineering and presents the three main types of empirical investigations — surveys, case studies, and formal experiments.

Software effort models and effort estimates help project managers allocate resources, control costs, and schedule and improve current practices, leading to projects that are finished on time and within budget. In the context of Web development and maintenance, these issues are also crucial, and very challenging, given that Web projects have short schedules and a highly fluidic scope. Therefore this chapter has two main objectives. The first is to introduce the concepts related to effort estimation and in particular Web effort estimation. The second is to present a case study where a real effort prediction model based on data from completed industrial Web projects is constructed step by step.

Project managers use software productivity measures to assess software development efficiency. Productivity is commonly measured as the ratio of output to input. Within the context of software development, output is often assumed to be product size and input to be effort. However, Web applications are often characterised using several different size measures and there is no standard model for aggregating those measures into a single size measure. This makes it difficult to measure Web application productivity.

In this chapter, we present a productivity measurement method, which allows for the use of different size measures. An advantage of the method is that it has a built-in interpretation scale. It ensures that each project has an expected productivity value of one. Values between zero and one indicate lower than expected productivity; values greater than one indicate higher than expected productivity. We demonstrate how to use the method by analysing the productivity of Web projects from the Tukutuku database.

In this chapter we analyse the different quality perspectives of software and Web applications. In particular, we review quality taking into account the ISO (International Organization for Standardization) standards for software product, and discuss the distinction between quality and quality in use, and how different requirements, from different users’ standpoints, should be considered as well. Moreover, we also describe Web quality and how it can be measured and evaluated. In order to illustrate the specific procedures and processes of an inspection evaluation methodology, a case study on the external quality of the shopping cart component of two typical e-commerce Web applications is presented.

Current Web applications are very complex and highly sophisticated software products, whose usability can greatly determine their success or failure. Defining methods for ensuring usability is one of the current goals of Web engineering research. Also, much attention is currently paid to usability by industry, recognising the importance of adopting methods for usability evaluation before and after application deployment. This chapter introduces principles and evaluation methods to be adopted during the whole application lifecycle for promoting usability. For each evaluation method, the main features, as well as the emerging advantages and drawbacks, are illustrated so as to support the choice of an evaluation plan that best fits the goals to be pursued and the available resources. The design and evaluation of a real application is also described for exemplifying the concepts and methods introduced.

Modern Web applications provide multiple services that are deployed through complex technologies. The importance and the economic impact of consumer-oriented Web applications introduce significant requirements in terms of performance and reliability. This chapter presents several methods to design new, and improve existing, Web applications that, even within a context of unpredictable load variations, must satisfy performance requirements. The chapter also provides a case study that describes the application of the proposed methods to a typical consumeroriented Web application.

Web applications are characterised by peculiarities that differentiate them from any other software application. These peculiarities affect their testing in several ways, which may result in harder than traditional application testing. Suitable methods and techniques have to be defined and used to test Web applications effectively. This chapter will present the main differences between Web applications and traditional ones, and how these differences impact the testing of Web applications. It also discusses relevant contributions in the field of Web application testing, proposed recently. The focus of the chapter is mainly on testing the functionality of a Web application, although discussions about the testing of non-functional requirements are provided too. Readers are required to have a general knowledge of software testing and Web technologies.

Existing software process improvement approaches can be applied successfully to small projects and small organisations. However, they need to customised and the techniques used have to be adapted for small settings. This chapter provides a pragmatic discussion of issues requires to implement software process improvement in small settings, covering the practical obstacles that are likely to be faced and ways to address them.

This chapter introduces a method that integrates navigational and presentational designs to object-oriented conceptual modelling, and also provides systematic code generation. The essential expressiveness is provided using graphical schemas that specify navigation and presentation features, and use high-level abstraction primitives. Using conceptual schemas as input, a methodology is defined to systematically take a problem space to the solution space by defining a set of correspondences between conceptual modelling abstractions and the final software components. We also provide a case study that details the application of the proposed methodology.

In this chapter we present our experience with the Object-Oriented Hypermedia Design Method (OOHDM), a model-based approach for developing Web applications. We first describe the main activities in OOHDM and then we illustrate the application of the method with a simple example, a CD store.