Configurable reference model quality

Numerous studies have been explored to ensure quality of the reference model. This study uses criteria for characterising references models described by Fettke et al. (2005). This is done in order to avoid shortcomings similar to was found in the development of reference models they studied, particularly around construction and evaluation. The limited application of standardised modelling languages in other reference models has been discussed by them, which is not an issue for this study as a global standard notation is being used. BPMN has been vetted and evaluated by other researchers as an effective means to represent the essential requirements of this study, i.e. control flow and related roles, events and data objects (Decker & Puhlmann, 2007; Dijkman, Dumas & Ouyang, 2008; Recker, 2010; Recker, Indulska, et al., 2006; Wohed, Aalst, Dumas, ter Hofstede & Russell, 2006). Fettke et al. (2005) also state that the construction method is not often explicated, and this problem has been addressed by making the entire approach and steps for construction transparently available to the reader in section 4.2 as normative guidelines. Based on their classification, the design method used for this reference model is “empiric-oriented design”. For evaluation, the core challenge identified by them is that a standardised set of evaluation criteria does not exist, especially one that balances the scientific demands of preciseness, completeness and consistency with the practical demands of simplicity and understandability. Studies have been found to emphasise understandability and practical application more than completeness, e.g. Ramias and Wilkins (2012), who indicate that unless that without this a reference model may not be beneficial to an organisation. This work therefore derives evaluation criteria guided by the research objective to cover each of these demands.

Embedding quality in the design of the reference model is endorsed by Matook and Indulska (2009). To do this, the work of Lindland, Sindre and Sølvberg (1994) as adapted by Mišić and Zhao (2000) has been used to propose criteria that can be used to evaluate quality of the reference model by evaluating quality of the process models themselves, i.e. in terms of syntactic (language), semantic (domain) and pragmatic (audience) properties. These often cited “Syntactic”, “Semantic” and “Pragmatic” properties from Lindland et al. (1994) provide a basis for the incorporation of modelling quality. Syntactic quality is ensured according to the correctness of the BPMN grammar. Syntactic correctness depends on the specifications of the selected language, in this case the BPMN specification (OMG, 2008). Semantic quality according to the business logic is ensured through validation by the personnel providing the information pertaining to the process, and for whose use these models are produced.

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Pragmatic quality is ensured through the feedback of personnel for whose use these models are produced, that the models are suitable and easy to use.

Figure 4 Model properties adapted from Lindland et al. (1994) by Mišić and Zhao (2000)

For the purpose of pragmatic quality, i.e. making the models easier to comprehend while also familiarising the end user with the principles of the notation, the Author of this thesis has introduced a small number of new symbols in the individual airport models. This is done to accommodate the construct deficit for depicting information related to spaces (Recker, Indulska, et al., 2006), and to capture advanced choreographies in the interest of efficient use of symbols (Decker & Puhlmann, 2007). Design of the introduced symbols is guided by Moody (2009) in that: they fulfil a construct deficit; the shape corresponds to the meaning; visual variables are used to encode information; text is used to complement the graphics; the number of new graphical symbols is cognitively manageable (less than 5); and finally the symbols are expressive and use different colours. These new symbols relevant to spaces that comply with guidelines from Moody (2009) are explained in detail in section 4.3.1. Further modelling guidelines are derived from the work of Rosemann (2006); Indulska, Recker, Rosemann and Green (2009); Mendling, Reijers and Aalst (2010); Recker, Rosemann and Aalst (2005); and Moody (2009), as listed in Table 1:

Table 1. Guidelines for model and modelling approach

GUIDELINES FOR THE MODEL PRODUCT GUIDELINES FOR THE MODELLING APPROACH

• Define appropriate level of detail

• Ensure model reflects executed process

• Maximise relevance in favour of completeness

• Minimise number of visual elements

• Minimise number of routing paths

• Maximise structuring of model

• Ensure standardised conventions are used

• Maximise value proposition to business

• Minimise interruption to the business

• Maximise applicability

• Embed quality in the modelling process to ensure the final product is of good quality

Language Domain

Audience

Model Semantics Syntax

Pragmatics

Chapter 2 Literature review

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Several other aspects are found in literature for the design and development of a high quality reference model. Stakeholder perspective and engagement representation in reference model design is found to be a gap by Schermann, Prilla, Böhmann, Krcmar and Herrmann (2012), which is a addressed by the selected process modelling notation that necessarily captures roles for every activity. In addition, terminology is perceived by Mendling (2012) and Winter and Schelp (2006) as an important consideration for reuse of models. The reference model is developed inductively via comparing and merging the As-Is, and consolidating findings into a suitable framework, to subsequently validate terminology with the domain experts, as emphasised by Seidel, Rosemann, ter Hofstede and Bradford (2006).

Quality criteria for the artefact have been derived by the Author of this thesis from the reference modelling and process modelling literature discussed in this section. The criteria are stated in section 3.3.4, and the final artefact is evaluated according to them in Chapter 6.

2.8. Chapter summary

Literature has been consulted in identifying scope and guidance for this project. The domain area for which modelling is to be done is international airports, which needs to be explored with respect to the internal and external factors that drive change thus influencing design of passenger facilitation and its environment. Literature has been found to guide modelling quality, to inform the design and development of reference models, and to provide awareness of issues around the notation thereby enabling their mitigation. Existing knowledge is found for guiding the merge of process models as a means for developing configurable reference process models via identification of similarities and differences. An application of contextual factors utilised in to make such a model configurable has yielded useful advice towards scoping and classifying context. This study combines questionnaire-driven and context-questionnaire-driven approaches by designing the questionnaire interface based on context information, specifically in the area of airport passenger facilitation. This enables the configurable model to generate possible model options of what the passenger facilitation process can look like based on different contexts.

A number of gaps that have been identified in literature are addressed by this project. First, a reference for airports based on current practices has not yet been developed. To address this, a configurable reference model is developed for the airport passenger flow in this project.

Second, BPMN notation does not enable explicit depiction of the impact of physical space on

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the process, which appears to be an important criterion for design of airport processes. This project adapts the notation to suit the airport modelling needs and accommodate space for the individual airports, and finds a suitable substitute in the canonised notation for the configurable reference model. Third, current airport process models for building the reference model have not been found to be available freely in industry or academic literature thereby a foundational modelling exercise needs to occur. Fourth, little is found to guide derivation of contextual factors that will be required for making the merged model configurable. An approach is proposed by this work to derive contextual factors, from an operational long-term design perspective, that influence operational design via the process variants. Fifth, a comprehensive set of normative guidelines is not found on how to develop a configurable reference model. To address this, the approach used in this project to develop the artefact is presented as a set of normative guidelines for others to use. The next chapter describes the research design for providing this contribution.