Collaborative Requirements

Engineering: Bridging the Gulf Between

WorldsAlistair SutclifeAlistair Sutclife

Tiago Soares Gonçalves

Professor: Jaelson Castro

Outubro/2010

Introdução Introdução

Introdução Introdução

Objetivo do artigoObjetivo do artigo

• Uma teoria do discurso da linguagem, , common ground [5], é usado como motivação método de engenharia/design para ER colaborativa,

• Avaliar como contribuições de diferentes representações (modelos) podem fazer para melhorar a compreensão mútua com as equipes de ER.

Common groundCommon ground

• Conversa, compreensão mútua e comum durante relação social ou dicursão, conhecimento mútuo, base acordada….

• Teoria da análise do dicurso de Clark [5]– The common ground theory or Clark’s linguistic theory of discourse [5]

describes the process by which mutual understanding is achieved though the process structure of human-human discourse”

Common groundCommon ground• Gerado a partir de 3 fontes de conhecimento:

1. Conhecimento detido pelos participantes sobre o outro durante a conversa

2. Conhecimento que vem do ambiente onde o diálogo acontece: artefatos do ambiente

3. Conhecimento compartilhado baseado em convenções sociais

• Diferentes camadas de conversas– Superfície = Expressão explícita = direto assunto– Camada de conhecimento tácito = mais profundo para interpretrações

Common groundCommon ground

Common groundCommon ground

Como conseguir um conversa efetiva?

Effective conversationEffective conversation

RE Representations and RE Representations and Communication ModalitiesCommunication Modalities

Síncrono – diálogos criam compreensão

mútua

Assíncrono – tempo para reflexão sobre o

problema

RE Representations and RE Representations and Communication ModalitiesCommunication Modalities

• Investigação do papel de diferentes documentos em ER. Desde representações ER pode experimentar múltiplas interpretações [11, 24] :

• Common ground é gerado por conversas entre stakeholders, acrescido de compreensão mútua de informações expressas em representações/modelos em ER

• Quanto mais acessível a representação melhor apoia a formação da base comum de conhecimento.

RE Representations and RE Representations and Communication ModalitiesCommunication Modalities

RE Representations and RE Representations and Communication ModalitiesCommunication Modalities

RE Representations and RE Representations and Communication ModalitiesCommunication Modalities

• storyboards e esboços são meios eficazes de promover a compreensão mútua. No entanto, estas representações são propenso a interpretações ambíguas para o entendimento entre as partes interessadas podem entrar em conflito.

• modelos informais podem reduzir a ambigüidade, possibilitando mais fácil análise, enquanto que os modelos formais podem eliminar a ambigüidade de raciocínio automatizado, porém com a desvantagem de mais difícil compreensão e acesso limitado através de grupos de interessados.

• …• Nenhuma representação unicamente será suficiente para apoiar o desenvolvimento de uma base comum, mas

sim, uma combinação é necessária para suportar diferentes atividades e fases do processo de requisitos

RE Activities, Representations RE Activities, Representations and Common Groundand Common Ground

• Activities in the RE road map [16] are reviewed from a common ground perspective while investigating the role for appropriate

representations.• Elicit and Summarize• Analyse and Reflect• Negotiate and Agree• Validate Communicate• Communication Requirements

Elicit and SummariseElicit and Summarise• Elicitation commences with little common ground between the users,

domain experts and requirements engineer. • This task involves not only capturing information but also making sure

that there is a shared understanding about domain facts and user goals.

• Representations play an important part in summarising information so it can be discussed and checked by all parties.

• The conversation has to progress towards a mutually agreed project: realisation of the users’ goals.

• Hence common ground has to be established between abstract and concrete views, which causes a tension that runs through all RE activities.

Analyse and ReflectAnalyse and ReflectConcreto

abstrato

Analyse and ReflectAnalyse and ReflectConcreto

abstrato

Informal models enable abstract viewpoints to be debated; but models may

hide ambiguities and, worse still, assertions may go

unchallenged.

Negotiate and AgreeNegotiate and Agree• Negotiating, prioritising and achieving mutually agreed

requirements all focus on the process of establishing common ground between stakeholders.

• Representations have a special role to play in this activity since common ground in conversation is limited by working memory to about five topics or ideas [1, 32].

• The representation becomes an external extension to our memory.

• Árvores de decisão

Validate and CommunicateValidate and Communicate• These activities have very different implications for common ground:1. Validation is the process of establishing that the requirements

specification and proposed system design satisfy users’ requirements– Mock-ups interativos, storyboards

2. Verification addresses checking and proving the correct internal behaviour of the specified– concerns only the software specialists – formal models and specifications– not accessible to users.

• Support both concrete and abstract views of requirements

Validate and CommunicateValidate and Communicate• These activities have very different implications for common ground:1. Validation is the process of establishing that the requirements

specification and proposed system design satisfy users’ requirements– Mock-ups interativos, storyboards

2. Verification addresses checking and proving the correct internal behaviour of the specified– concerns only the software specialists – formal models and specifications– not accessible to users.

• Support both concrete and abstract views of requirements

Managing RE ConversationsManaging RE Conversations

ADVISES Case StudyADVISES Case Studya decision-support system for analysis of epidemiology problems that served two stakeholder groups: academic researchers and public health analysts.

ADVISES Case StudyADVISES Case Studya decision-support system for analysis of epidemiology problems that served two stakeholder groups: academic researchers and public health analysts.

ConclusõesConclusões• The contributions of this chapter have been to develop Rolland’s

vision of method engineering from the perspective of discourse theory and natural language.

• Application of Clark’s common ground as a framework for critiquing representations and techniques throws light on their relative contributions to one of the fundamental problems in RE: how to reconcile abstract and concrete views in system development, so that a mutual understanding of requirements, the software design and domain constraints emerges