Web Development Effort Estimation: An Empirical Analysis

Web Development Effort Estimation: An Empirical Analysis

Emilia Mendes (The University of Auckland, New Zealand) and Silvia Abrahão (Valencia University of Technology, Spain)
Copyright: © 2008 |Pages: 31
DOI: 10.4018/978-1-59904-847-5.ch002
OnDemand PDF Download:
$37.50

Abstract

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, the objective of this chapter is to introduce the concepts related to Web effort estimation and effort estimation techniques. In addition, this chapter also details and compares, by means of a case study, three effort estimation techniques, chosen for this chapter because they have been to date the ones mostly used for Web effort estimation: Multivariate regression, Case-based reasoning, and Classification and Regression Trees. The case study uses data on industrial Web projects from Spanish Web companies.

Key Terms in this Chapter

Prediction at Level l: Also known as Pred(l). It measures the percentage of estimates that are within l% of the actual values.

Case-Based Reasoning: Assumes that similar problems provide similar solutions. It provides estimates by comparing the characteristics of the current project to be estimated against a library of historical information from completed projects with a known effort (case base).

Effort Estimation: To predict the necessary amount of labour units to accomplish a given task, based on knowledge of previous similar projects and other project characteristics that are believed to be related to effort. Project characteristics (independent variables) are the input, and effort (dependent variable) is the output we wish to predict.

Mean Magnitude of Relative Error: Calculates the Mean Magnitude of Relative Error (MRE), which measures for a given project the difference between actual and estimated effort relative to the actual effort. The mean takes into account the numerical value of every observation in the data distribution, and is sensitive to individual predictions with large MREs.

Classification and Regression Trees (CART) (Brieman et al., 1984): Techniques where independent variables (predictors) are used to build binary trees where each leaf node either represents a category to which an estimate belongs to, or a value for an estimate. In order to obtain an estimate one has to traverse tree nodes from root to leaf by selecting the nodes that represent the category or value for the independent variables associated with the case to be estimated.

Expert-Based Effort Estimation: Represents the process of estimating effort by subjective means, and is often based on previous experience from developing/managing similar projects. This is by far the mostly used technique for Web effort estimation. Within this context, the attainment of accurate effort estimates relies on the competence and experience of individuals (e.g., project manager, developer).

Cross-Validation: Process by which an original dataset d is divided into a training set t and a validation set v. The training set is used to produce an effort estimation model (if applicable), later used to predict effort for each of the projects in v, as if these projects were new projects for which effort was unknown. Accuracy statistics are then obtained and aggregated to provide an overall measure of prediction accuracy.

Algorithmic Techniques: Attempt to build models that precisely represent the relationship between effort and one or more project characteristics via the use of algorithmic models. Such models assume that application size is the main contributor to effort thus in any algorithmic model the central project characteristic used is usually taken to be some notion of application size (e.g., the number of lines of source code, function points, number of Web pages, number of new images). The relationship between size and effort is often translated as an equation.

Complete Chapter List

Search this Book:
Reset
Editorial Advisory Board
Table of Contents
Acknowledgment
Coral Calero, M. Angeles Moraga, Mario Piattini
Chapter 1
Emilia Mendes
Surveying and classifying previous work on a particular field brings several benefits, which are: 1) to help organise a given body of knowledge; 2)... Sample PDF
Sizing Web Applications for Web Effort Estimation
$37.50
Chapter 2
Emilia Mendes, Silvia Abrahão
Effort models and effort estimates help project managers allocate resources, control costs and schedule, and improve current practices, leading to... Sample PDF
Web Development Effort Estimation: An Empirical Analysis
$37.50
Chapter 3
Pankaj Kamthan
The significance of approaching Web information systems (WIS) from an engineering viewpoint is emphasized. A methodology for deploying patterns as... Sample PDF
Patterns for Improving the Pragmatic Quality of Web Information Systems
$37.50
Chapter 4
Rosemary Stockdale, Chad Lin
Many small and medium sized businesses (SMEs) have set up their own Web sites, as part of their business strategies, to improve their... Sample PDF
Evaluation of the Effectiveness of Small and Medium Sized Businesses Web Sites in a Business to Business Context
$37.50
Chapter 5
May Haydar, Ghazwa Malak, Houari Sahraoui, Alexandre Petrenko, Sergiy Boroday
This chapter addresses the problem of Web application quality assessment from two perspectives. First, it shows the use of model checking of... Sample PDF
Anomaly Detection and Quality Evaluation of Web Applications
$37.50
Chapter 6
Thomas Mandl
Automatic quality assessment of Web pages needs to complement human information work in the current situation of an information overload. Several... Sample PDF
Automatic Quality Assessment for Internet Pages
$37.50
Chapter 7
Mª Ángeles Moraga, Julio Córdoba, Coral Calero, Cristina Cachero
The success of Web portals has increased over time, in such a way that a portal user can choose among a wide variety of portals. Therefore, the... Sample PDF
A General View of Quality Models for Web Portals and a Particularization to E-Banking Domain
$37.50
Chapter 8
Angélica Caro, Coral Calero, Mario Piattini
Web portals are Internet-based applications that provide a big amount of data. The data consumer who uses the data given by these applications needs... Sample PDF
A Data Quality Model for Web Portals
$37.50
Chapter 9
Marta Fernández de Arriba, Eugenia Díaz, Jesús Rodríguez Pérez
This chapter presents the structure of an index which serves as support so allowing the development team to create the specification of the context... Sample PDF
Specification of the Context of Use for the Development of Web-Based Applications
$37.50
Chapter 10
Web Accessibility  (pages 163-180)
Carlos García Moreno
This chapter faces the Web accessibility issue from the perspective of Web Information Systems Quality, which is the main topic of the handbook. The... Sample PDF
Web Accessibility
$37.50
Chapter 11
Adriana Martín, Alejandra Cechich, Gustavo Rossi
Web accessibility is one facet of Web quality in use, and one of the main actors upon which the success of a Web site depends. In spite of these... Sample PDF
Comparing Approaches to Web Accessibility Assessment
$37.50
Chapter 12
Soonhwa Seok
Digital inclusion and Web accessibility are integral parts of modern culture and, as such, have implications for social accountability. The World... Sample PDF
Maximizing Web Accessibility Through User-Centered Interface Design
$37.50
Chapter 13
Francisco Montero, María Dolores Lozano, Pascual González
World Wide Web software development is a challenge. The need to provide appealing and attractive user interfaces is combined with the fact that the... Sample PDF
Usability-Oriented Quality Model Based on Ergonomic Criteria
$37.50
Chapter 14
Maristella Matera, Francesca Rizzo, Rebeca Cortázar, Asier Perallos
Given the emergent need for usability, during last year’s traditional development processes have been extended for enabling the fulfillment of... Sample PDF
The Usability Dimension in the Development of Web Applications
$37.50
Chapter 15
Fernando Bellas, Iñaki Paz, Alberto Pan, Óscar Díaz
Portlets are interactive Web mini-applications that can be plugged into a portal. This chapter focuses on “portletizing” existing Web applications... Sample PDF
New Approaches to Portletization of Web Applications
$37.50
Chapter 16
Victoria Torres, Joan Fons, Vicente Pelechano
Users consider usability aspects as a key factor when using Web applications. For this reason, in this work we take a special care in this very... Sample PDF
Handling Usability Aspects for the Construction of Business Process Driven Web Applications
$37.50
Chapter 17
Nicolas Guelfi, Cédric Pruski, Chantal Reynaud
The evolution of Web information is of utmost importance in the design of good Web Information Systems applications. New emerging paradigms, like... Sample PDF
Towards the Adaptive Web Using Metadata Evolution
$37.50
Chapter 18
Carmen Martínez-Cruz, Ignacio José Blanco, M. Amparo Vila
The Semantic Web has resulted in a wide range of information (e.g., HML, XML, DOC, PDF documents, ontologies, interfaces, forms, etc.) being made... Sample PDF
Looking for Information in Fuzzy Relational Databases Accessible Via Web
$37.50
Chapter 19
Ricardo Barros, Geraldo Xexéo, Wallace A. Pinheiro, Jano de Souza
Currently, in the Web environment, users have to deal with an enormous amount of information. In a Web search, they often receive useless... Sample PDF
A Web Metadata Based-Model for Information Quality Prediction
$37.50
Chapter 20
Fernando Molina, Francisco J. Lucas, Ambrosio Toval Alvarez, Juan M. Vara, Paloma Cáceres, Esperanza Marcos
Recent years have seen the arrival of the Internet as the platform that supports most areas within organizations, a fact which has led to the... Sample PDF
Towards Quality Web Information Systems Through Precise Model-Driven Development
$37.50
Chapter 21
M.J. Escalona, G. Aragón
The increasing complexity and the many different aspects that should be treated at the same time require flexible but powerful methodologies to... Sample PDF
The Use of Metamodels in Web Requirements to Assure the Consistence
$37.50
Chapter 22
Cristina Cachero Castro, Coral Calero, Yolanda Marhuenda García
This chapter introduces the necessity to consider quality management activities as part of the Web engineering (WE) process to improve the final... Sample PDF
A Quality-Aware Engineering Process for Web Applications
$37.50
Chapter 23
Sergej Sizov, Stefan Siersdorfer
This chapter addresses the problem of automatically organizing heterogeneous collections of Web documents for the generation of thematically-focused... Sample PDF
Restrictive Methods and Meta Methods for Thematically Focused Web Exploration
$37.50
Chapter 24
Mª Ángeles Moraga, Ignacio García-Rodríguez de Guzmán, Coral Calero, Mario Piattini
The use of Web portals continues to rise, showing their importance in the current information society. Specifically, this chapter focuses on... Sample PDF
WSRP-O: An Ontology to Model WSRP Compliant Portlets
$37.50
Chapter 25
Tony C. Shan, Winnie W. Hua
This article defines a comprehensive set of guiding principles, called philosophy of architecture design (PAD), as a means of coping with the... Sample PDF
Philosophy of Architecture Design in Web Information Systems
$37.50
Chapter 26
Mohamed Salah Hamdi
Conventional Web search engines return long lists of ranked documents that users are forced to sift through to find relevant documents. The... Sample PDF
Improving the Quality of Web Search
$37.50
Chapter 27
Jengchung V. Chen, Wen-Hsiang Lu, Kuan-Yu He, Yao-Sheng Chang
With the fast growth of the Web, users often suffer from the problem of information overload, since many existing search engines respond to queries... Sample PDF
The Perspectives of Improving Web Search Engine Quality
$37.50
Chapter 28
Xiannong Meng
This chapter surveys various technologies involved in a Web search engine with an emphasis on performance analysis issues. The aspects of a... Sample PDF
Web Search Engine Architectures and their Performance Analysis
$37.50
Chapter 29
Fotis Lazarinis
As the Web population continues to grow, more non-English users will be amassed online. The purpose of this chapter is to describe the methods and... Sample PDF
Towards a Model for Evaluating Web Retrieval Systems in Non-English Queries
$37.50
Chapter 30
John D. D’Ambra, Nina Mistillis
This chapter considers the change in information seeking behaviour of tourists as a result of the increased use of the World Wide Web as an... Sample PDF
Web Information Resources Vis-à-Vis Traditional Information Services
$37.50
About the Contributors