a fuzzy ahp method to support sustainability reporting an application to the water technology

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    10%

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    Materials

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    Assessment

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    Mechanisms

    Materiality of GRI aspects under the environmental category

    aphical Abstract (for review)

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      A fuzzy AHP method to prioritize ‘materiality’ of  sustainability aspects and indicators

      The proposed method is based on the G4 GRI Guidelines

      The method is especially useful for supporting SMEs in sustainability reporting

    ghlights (for review)

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    A fuzzy AHP method to support sustainability reporting: an application to the water

    technology industry

     Armando Calabrese1 , Roberta Costa

    1*, Nathan Levialdi

    1 , Tamara Menichini

    1 Department of Enterprise Engineering, University of Rome “Tor Vergata”, Italy

    * corresponding author: Roberta Costa

    Address: University of Rome Tor Vergata, Department of Enterprise Engineering, Via del

    Politecnico 1, 00133 Rome, Italy.

    tel.: 0039 06 72597799

    fax.: 0039 06 72597951

    e-mail: [email protected] 

    le page

    mailto:[email protected]:[email protected]:[email protected]:[email protected]

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    1

    A fuzzy AHP method to support sustainability reporting: an application to the water

    technology industry

    Abstract

    Sustainability reporting encourages companies to set goals and measure their performance in

    the sustainability of operations concerning economic, environmental and social impacts. 

    However not all sustainability issues have the same relevance for every organization.

    Company reporting must cover the ‘material’ aspects of sustainability, meaning the areas that

    can be positively or negatively affected by their activities. Reporting on the material aspects

    of sustainability provides greater transparency for stakeholders, and achieves greater

    accountability of the companies for their actions and effects.

    This paper proposes a ‘fuzzy analytic hierarchy process’ (fuzzy AHP) method to support the

    identification and prioritization of the company’s material sustainability aspects. Based on the

    Global Reporting Initiative (GRI) G4 Guidelines, the method evaluates the significance of

    GRI ‘Aspects’ and ‘Indicators’ for reporting the company’s sustainability performance. The

    fuzzy AHP method prioritizes the aspects and indicators for inclusion in the report, thus

    assisting company managers to disclose results effectively, while also managing the time and

    financial constraints that can restrict their efforts in sustainability reporting. To illustrate the

    method, the paper presents a case study of an Italian SME active in the water technology

    industry.

    Keywords: sustainability reporting; Global Reporting Initiative (GRI); fuzzy Analytic

    Hierarchy Process (AHP); small and medium enterprises (SMEs)

    anuscript

    ck here to view linked References

    http://ees.elsevier.com/jclepro/viewRCResults.aspx?pdf=1&docID=13020&rev=0&fileID=340440&msid={A662572E-2A92-4404-BFAA-ED9FF33E4C43}http://ees.elsevier.com/jclepro/viewRCResults.aspx?pdf=1&docID=13020&rev=0&fileID=340440&msid={A662572E-2A92-4404-BFAA-ED9FF33E4C43}

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    1. Introduction

    Company sustainability depends on awareness of corporate responsibilities. Sustainable

    companies interact with society, the economy and environment, considering the needs of both

     present and future stakeholders, working towards goals of sustainable development

    (Robinson, 2004). Sustainability reporting, or the practice of measuring and disclosing the

    company’s  sustainability performance, ensures accountability to stakeholders and supports

    the company in managing change towards operation in a more sustainable manner

    (Bebbington, 2001; GRI, 2013a, 2013b). Transparent communication improves the credibility

    of the company’s environmental and social commitments and favours its long-term processes

    of value creation (Birth et al., 2008; Schmeltz, 2014).

    However differing organizational characteristics, such as the business model, size, ownership

    and social and cultural context, affect both company impacts and the stakeholder expectations

    concerning sustainability (Porter and Kramer, 2006). Because of this, not all aspects of

    sustainability have the same relevance for every company (GRI, 2013a, 2013b; ISO, 2010).

    For a company to be truly accountable to stakeholders, it is crucial that it identify which

    sustainability-related content to disclose, and identify the appropriate levels of detail for

    reporting the information (Kolk, 2008). The Global Reporting Initiative (GRI) Sustainability

    Reporting Guidelines, which is the best known framework for sustainability reporting,

    stresses the importance of focusing on the ‘material’ aspects of sustainability (Marimon et al.,

    2012). The ‘material’  sustainability aspects are those that significantly reflect the company

    economic, environmental and social impacts (GRI, 2013b). For more transparent and

    coherent disclosure of its sustainability performance, the company must identify and

     prioritize those aspects and indicators that are material (GRI, 2013a, 2013b). Ideally,

    companies would be able to draw on quantitative methods to assess the relative material

    importance of sustainability aspects and indicators of multidimensional performance, and

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    3

    thus plan and act accordingly (Lozano, 2013; Lozano and Huising, 2011). Few scholars have

    inquired into potential quantitative methods for assessing the relative importance of the

    different aspects of sustainability (Arena and Azzone, 2012; Hsu et al., 2013; Krajnc and

    Glavic, 2005;). To respond to the methodological scarcity, the current paper proposes, applies

    and examines a ‘fuzzy analytic hierarchy process’ (fuzzy AHP) method, involving multi-

    criteria decision-making (MCDM) and fuzzy linguistic variables, to support companies in

    defining the content of their sustainability report. The method offers advantages in terms of

    accuracy, thoroughness and efficiency of reporting, as well as generalizability among

    companies. The methodological integration of fuzzy variables serves to manage the

    ambiguity and uncertainty of subjective judgments, typical in evaluating the ‘materiality’ of

    the different sustainability issues (Chen and Fan, 2011). The method is based on the G4 GRI

    Guidelines (GRI, 2013a, 2013b), currently in world-wide use. It allows the company to

    determine the relative importance and utility of the different GRI ‘Aspects’ and ‘Indicators’ 

    in assessing sustainability performance in environmental, economic and social areas.

    Application of the fuzzy AHP method supports companies in the process of defining the

    ‘material’ content for sustainability reporting, permitting them to identify those GRI aspects

    and indicators that better address their key sustainability concerns. The method should be

    especially useful to SMEs, which often face time and financial constraints as they engage in

    sustainability reporting (Baumann-Pauly et al., 2013), but supports all companies that wish to

    ‘make reports more relevant, more credible and more user-friendly’ (GRI, 2013a, p. 3).

    The next section of the paper provides a brief review of the literature on sustainability

    reporting and the GRI Guidelines. Section 3 reviews the theory of the fuzzy AHP approach

    and develops the proposed method. Section 4 presents an application of the method to the

    case of an Italian SME and Section 5 illustrates its usefulness as a tool to support

    sustainability reporting. Finally, Section 6 summarizes and concludes the study.

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    4

    2. Literature review 

    2.1 Sustainability reporting

    ‘Sustainability reporting is the practice of measuring, disclosing, and being accountable to

    internal and external stakeholders for organizational performance, towards the goal of

    sustainable development’ (GRI, 2006, p. 3). Sustainability reporting has been the subject of

    growing attention from policy makers, market regulators, stakeholders, managers and

    academics, and thus the practice of reporting has increased significantly over the last two

    decades (GRI, 2013c). The literature offers different theoretical and empirical explanations

    concerning the motivations and drivers for sustainability reporting (Burritt and Schaltegger,

    2010; Herzig and Schaltegger, 2011). Currently, the main approaches to the issue are

    ‘impression management theory’, ‘signaling theory’  and ‘legitimacy theory’(Dawkins and

     Ngunjiri, 2008). In impression management theory, sustainability reporting is viewed as a

    way to manage stakeholder perceptions, while under signaling theory, the company uses

    reporting to ‘communicate company values’  (Hooghiemstra, 2000; Mahoney et al., 2013).

    Legitimacy theory instead presents reporting as a way to face the increasing demands,

    arriving from various actors, that companies must manage their impacts (Deegan, 2002).

    Through sustainability reports, stakeholders can establish if a company’s activities are in line

    with their values and expectations, and consequently approve or ‘disapprove’ of the actions.

    Appropriate reporting enhances company-stakeholder relationships (Calabrese et al., 2013b)

    and so contributes to processes for the creation of shared value, connecting society with

    economic progress (Porter and Kramer, 2011).

    In spite of the advantages, some companies can be inhibited from sustainability reporting due

    to the added resources required for conforming to accountability procedures, both in finances

    and the acquisition and training of competencies (Kolk, 2005). The company’s organizational 

    characteristics, such as its business model, cultural operating contexts, size and ownership,

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    5

    will affect sustainability practices and reporting (Adams, 2002; Belal and Copper, 2011;

    Gamerschlag et al., 2011; Hahn and Kuhnen, 2013; Lepoutre and Heene, 2006; Meyskens

    and Paul, 2010). A study by Baumann-Pauly, Wickert, Spence and Scherer (2013) reveals a

    ‘sustainability reporting gap’  relative to company size: large companies adopt strong

    reporting, aiming to improve their image with the general public; SMEs tend to concentrate

    their efforts at communication on their most important stakeholders, particularly employees,

    adopting only informal mechanisms. For SMEs, the reporting gap derives primarily from a

    lack of time and the specialized knowledge and financial resources necessary for appropriate

    documentation of sustainability performance. The ‘reporting gap’  both contributes to and

    derives from the low visibility of smaller companies.

    SMEs are thus reluctant to adopt the existing international frameworks of standards for

    sustainability practice and reporting (Kolk, 2005). Sustainability standards are a form of

    voluntary accreditation and self-regulation, aimed at encouraging companies to adopt

    systematic approaches to stakeholder engagement in sustainability practice, and at improving

    comparability in performance (Ligteringen and Zadek, 2005). Koerber (2010) classifies

    sustainability standards as: ‘ Normative Frameworks, Management Systems, and Process

    Guidelines’. Normative Frameworks regulate performance and goals (e.g. OECD Guidelines

    for Multinational Enterprises). Management Systems regulate the integration of social and

    environmental issues with the company operations (e.g. Social Accountability SA8000).

    Process Guidelines offer guidance on measurement, communication and assurance (e.g. GRI

    Reporting Framework).

    The method proposed in the current paper is based on the GRI Guidelines, which are the most

    widely used framework for voluntary sustainability reporting (Marimon et al., 2012). The

    following subsections provide a brief review of the G4 GRI Guidelines (GRI, 2013a, 2013b)

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    and some of the advantages of this standard. Subsequently, we examine how their

    implementation can be supported by a fuzzy AHP method.

    2.2 GRI Sustainability Reporting Guidelines

    The GRI Sustainability Reporting Guidelines combine reporting of financial and non-

    financial information in a standardized framework, resulting in full characterization of the

    company’s sustainability performance in the economic, environmental and social dimensions

    (GRI, 2013a, 2013b).

    The GRI Guidelines are appropriate for sustainability reporting regardless of company

    dimension or industrial sector (Bouten et al., 2011). The guidelines offer companies a series

    of potential advantages: they permit standardization in the contents of reporting and the

     processes of implementation; they can improve stakeholder relationships; they permit

    comparison to the practices and performance of other organizations (Fortanier et al., 2011;

    Koerber, 2010; Schadewitz and Niskala, 2010). The guidelines are developed by multi-

    stakeholder technical working groups, with the aim of obtaining flexibility and global

    relevance. The guidelines are structured to elicit company reporting on both the positive and

    negative effects of their activities, ensuring stakeholders a reasonable and balanced

    representation of the sustainability practices and performance. Company use of the guidelines

    enhances accountability, by taking into account the expectations and viewpoints of different

    types of stakeholders about engagements in sustainability (Brown et al, 2009).

    GRI Guidelines analyze sustainability issues not only in terms of negative impact reduction,

     but also in terms of wealth creation and distribution. This characteristic ensures that

    companies address ‘eco-efficiency’ (environmental impact) and ‘eco- justice’ (wealth creation

    and distribution) issues, and consider future patterns of development (Bebbington, 2001).

    The current paper applies the most recent generation of GRI Guidelines, known as ‘G4’

    (GRI, 2013a, 2013b).

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    2.2.1 The G4 framework  

    G4 considers sustainability performance under a framework of three ‘Categories’:

    ‘Economic, Environmental, Social’. The Social Category is further divided into four ‘Sub-

    Categories’: Labor Practices and Decent Work, Human Rights, Society, and Product

    Responsibility. The actual description of sustainability under the Categories and Sub-

    Categories is accomplished by applying specific ‘Aspects’ and ‘Indicators’ (Table 1).

    --------------------------------------------

    INSERT TABLE 1 ABOUT HERE

    -------------------------------------------

    2.2.2 ‘M ateriality ’ in sustainabil ity reporti ng  

    The G4 Guidelines stress the importance of providing reports that are material to the

    company’s business and stakeholders, meaning ‘centered on matters that are really critical in

    order to achieve the organization’s goals and manage its impact on society’ (GRI, 2013a, p.

    3). To accomplish this, the reports must deal with the specific GRI aspects and indicators that

    are in turn material. An aspect is material if it has significant relevance to the company’s 

    economic, environmental and social impacts; an aspect is immaterial if it is not sufficiently

    relevant (GRI, 2013a, 2013b). In addition, an aspect is deemed ‘not applicable’ when it is

    completely unsuitable for describing the areas of company sustainability performance. In this

    case it is excluded from the sustainability report, and the reasons for this decision must be

    explained.

    The objective of the so-called ‘Materiality Principle’ is to provide stakeholders with relevant,

    complete and coherent information for the assessment of company performance. For this, the

    G4 reporting guidelines recommend that companies prioritize the GRI aspects in terms of

    their relative significance (materiality) in revealing sustainability performance. The

    materiality principle must then also be applied to the indicators for the GRI aspects that are

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    8

    more significant: first the company must select the indicators that are material to measuring

    the sustainability performance; second, the indicators must be prioritized. Finally, the report

    should offer appropriate ‘levels of detail’, meaning combinations of indicators, quantitative

    measures and narrative information suitable to the significance of each aspect judged as

    material.

    In the next section we propose a fuzzy AHP method to support companies in identifying the

    GRI aspects and indicators that are more significant to disclosing the company’s

    sustainability performance.

    3. The fuzzy AHP method for decisions in sustainability reporting

    The ‘analytic hierarchy process’ (AHP) is a structured technique for organizing and analyzing

    complex decisions. It provides a comprehensive framework for structuring a decision-making

     problem: representing and quantifying its elements, relating these elements to an overall goal.

    AHP decomposes the overall problem into a hierarchy of readily comprehended sub-

     problems and further items. The procedure permits the inclusion of both quantitative and

    qualitative criteria in the evaluation process.

    In this paper we adopt the ‘fuzzy’ extension of classic AHP, an approach that deals with the

    vagueness or fuzziness of the linguistic and subjective judgments typically formulated in

    decision-making processes (Chen and Fan, 2011). In sustainability reporting, such fuzziness

    is characteristic of the stage in which company decision-makers must judge the GRI aspects

    and indicators material to the disclosure of sustainability performance. We expect the fuzzy

    AHP method to assist in the assessment of the relative significance of the GRI aspects and

    indicators.

    In the following subsections we explain fuzzy AHP in more detail and develop the method

    for application to the problem at hand.

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    3.1 AHP and fuzzy AHP 

    AHP is a decision-making approach used to arrive at solutions to complex multiple-criteria

     problems involving qualitative judgements (Saaty, 1980). The process decomposes the

    decision-making process into constituent parts, progressing from the general to the specific.

    The problem is structured in hierarchical form, with the overall decision-making goal at the

    top, above the lower levels of criteria and alternatives. Each criterion or sub-criterion can be

    further divided into appropriate levels of detail. Finally, the decision alternatives or selection

    choices are laid down at the last level of the hierarchy.

    Decision-makers decompose their problem into the hierarchy, and then progressively judge

    the importance of each criterion in paired comparisons. The judgement is performed from the

     point of view of the next criterion up. The judgements score the decision alternatives, one

    relative to another. The process includes consideration of subjective opinions, gathered by

    direct questioning or questionnaires that reveal the necessary decision-making information

    and the priority weighting of the elements. The AHP process thus captures both subjective

    and objective criteria in decision-making, while providing an instrument for checking the

    coherence of the decision-makers’ evaluations (Saaty, 1980).

     Nevertheless AHP does not completely capture the peculiarities of qualitative assessment

     because its discrete scale cannot reflect the true character of human thinking (Huang et al.,

    2008). Given that expert preferences are almost universally affected by uncertainty and

    imprecision, it is unrealistic to use definite and precise numbers to represent the entailing

    linguistic judgments (Kwong and Bai, 2003). The ‘fuzzy AHP method’ provides a means to

    deal with this ambiguity, by integrating ‘triangular fuzzy numbers’ (TFNs) and classic AHP

    in a single process. The fuzzy AHP method is thus better suited to solving decision-making

     problems concerning subjective evaluations.

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    Fuzzy AHP converts linguistic judgments into TFNs, organized in fuzzy pair-wise

    comparison matrices. Many methods of ‘comparison matrices’  have been introduced (e.g.

    Chang, 1996; Csutora and Buckley, 2001), to obtain the relative weights of the decision items

    (criteria, subcriteria and alternatives). Among others methods, the fuzzy extension of AHP

     proposed by Chang (1996) is well known and widely applied. However Wang et al. (2008)

    demonstrate that it can lead to incorrect prioritization, through assigning ‘zero weights’ to

    some decision items and thus excluding them from the analysis. To avoid this shortcoming

    we adopt a fuzzy AHP approach proposed by Calabrese et al. (2013a), which resolves the

    zero weight issue, taking into account Wang et al.’s (2008) criticisms of Chang’s method and

    the consistency test of Kwong and Bay (2003). The following section details how the general

    fuzzy AHP method can be applied to the particular problem of judging the materiality of GRI

    aspects and indicators.

    3.2 The hierarchical structure for identifying ‘materiality’

    As described, fuzzy AHP structures complex decisions as a hierarchy, from the overall

    objective at the top to criteria, subcriteria, and downwards  to lower levels. Moreover the

    hierarchical structure of fuzzy AHP remains flexible, permitting different levels of detail to

    reflect the peculiarities of each decision problem.

    In this case, to take account of the multi-dimensional nature of company sustainability

     performance (economic, environmental and social dimensions), we propose a model

    consisting of three hierarchical structures of criteria and subcriteria. The GRI sub-categories,

    aspects and indicators are organized in three separate hierarchies, in keeping with the three

    sustainability categories of the G4 Guidelines. At the top level of the hierarchical structures is

    the goal of each analysis. Each goal is formulated in terms of deciding the more significant or

    ‘material’ aspects and indicators, relevant to the three dimensions of sustainability

    (economic, environmental, social) as identified in the GRI guidelines:

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       Economic Goal ‒   The goal of the economic hierarchy is to assess the level of

    significance of the GRI aspects and indicators of the economic category, deciding

    those aspects that best reflect the company’s economic impacts and the indicators that

     best allow assessment of its economic sustainability performance. Economic impacts

    can be direct and indirect. The direct ones result from company economic activities,

    transactions and interactions in specific markets. Indirect impacts are those that have

    an indirect effect on stakeholders, such as investments that are realized for broader

     public benefit (GRI, 2013a, 2013b);

     

     Environmental Goal ‒  The goal of the environmental hierarchy is to assess the level

    of significance of the GRI aspects and indicators of the environmental category,

    deciding those aspects that best reflect the company’s environmental impacts and the

    indicators that allow assessment of its environmental sustainability performance. The

    environmental impacts refer to those caused by the inputs and the outputs of company

     processes: energy and water consumption, gas emissions, biodiversity protection,

    waste recycling, sustainability in transport, and disposal of products and materials

    (GRI, 2013a, 2013b);

      Social Goal ‒  The goal of the social hierarchy is to assess the level of significance of

    the GRI aspects and indicators of the social category, deciding those aspects that best

    reflect the company’s  social impacts and the indicators that allow assessment of its

    social sustainability performance. Social impacts concern the effects of company

    activities on social systems: work practices, respect of human rights, public policy,

    consumer health and safety protection (GRI, 2013a, 2013b).

    Under each goal are structured the related GRI aspects, with the next level down being the

    GRI indicators (Figures 1, 2, 3). The social hierarchical structure presents a further level of

    criteria corresponding to the GRI ‘Social Sub-Categories’.

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    ---------------------------------------------------

    INSERT FIGURES 1, 2, 3 ABOUT HERE

    ---------------------------------------------------

    3.3 Conversion of decision-maker judgments to relative weights

    Given the proposed hierarchical structures (Figures 1, 2, 3), decision-makers can now be

    asked to compare the relevance of GRI aspects and indicators, in pair-wise comparisons,

    under the economic, environmental and social goals of the analysis.

    The decision-makers judge the relative importance of the items in a pair by means of

    linguistic terms: ‘equally’, ‘weakly more’, ‘moderately more’, ‘strongly more’ or ‘extremely

    more important’. The  linguistic judgments are then converted into triangular fuzzy numbers

    (TFNs) using the scale shown in Table 2.

    ---------------------------------------------------

    INSERT TABLE 2 ABOUT HERE

    ---------------------------------------------------

    The TFNs are organized in fuzzy comparison matrices (1):

    12 12 12   1 1 1

    21 21 21   2 2 2

    1 1 1 2 2 2

    (1,1,1) ( , , )   ( , , )

    ( , , ) (1,1,1)   ( , , )

    ( , , ) ( , , )   (1,1,1)

    n n n

    n n nij n n

    n n n n n n

    l m u   l m u

    l m u   l m u A a

    l m u l m u

           

     

      (1)

    where

    1   1 1 1( , , ) ( ) , , , , 1,... ;ij   ij ij ij ji

     ji ji ji

    a l m u a i j n i ju m l 

     

      (2)

    is a TFN that represents the linguistic judgment for the items i with respect to  j performed

    from the perspective of the next criterion up.  A  is a square, symmetrical matrix.

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    The fuzzy AHP method proposed by Calabrese et al. (2013a) is then applied to each

    comparison matrix (steps 1 to 4, below), thus identifying the relative weights of the GRI

    aspects and indicators, without the problem of zero weights.

    Step 1. Convert the fuzzy comparison matrix (1) into a crisp comparison matrix using the

    centroid defuzzification method called ‘center of gravity’ (Yager, 1981). In the case of TFNs

    the translating formula is (Wang and Elhang, 2007):

    ( ) , , 1,...,3

    ij ij ijij ij

    l m ua a i j n

      (3) 

    Step 2.  Analyze the consistency of the comparison matrix by calculating the consistency

    index (CI ) and the consistency ratio (CR):

    max( )

    1

    nCI 

    n

       

      (4)

    100%CR CI RI n   (5)

    where  max    is the largest eigenvalue of the comparison matrix, n  is the dimension of the

    matrix and RI (n) is a random index depending on n as shown in Table 3.

    ---------------------------------------------------

    INSERT TABLE 3 ABOUT HERE

    ---------------------------------------------------

    Usually, the consistency of the matrix is acceptable only if CR (5) is less than 10% (Forman,

    1990). However the threshold of 10% can be reduced or increased depending on the tolerance

    of the decision-makers (Alonso and Lamata, 2006). If a matrix results as inconsistent, new

     pair-wise comparison judgments must be obtained, for preparation of a new pair-wise fuzzy

    comparison matrix and a repeat analysis. The matrix review must be continued until

    consistency is obtained.

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    Step 3 . Determine the local priority weight of each criterion, sub-criterion and alternative by

    summing up each row of the consistent fuzzy comparison matrix  A  (6) and then normalizing

    the row sums to obtaini

    S   by means of (7).

    1 1 1 1

    ( , , ), 1,...,n n n n

    i ij ij ij ij j j j j

     RS a l m u i n

      (6)

    1 1 1

    1 1, 1 1, 1 1 1, 11

    , , ( , , ), 1,...,

    n n n

    ij ij ij j j ji

    i i i in n n n n n n nn

    ij kj kj ij kj j j k k i j k j j k k i j j

    l m u RS 

    S l m u i n

    l u m u l   RS 

     

      (7)

    Finally, the crisp weights are calculated converting fuzzy weights as follows:

    ( ) , 1,...,3

    i i ii i i

    l m uw S S i n

      (8)

    Via normalization, the normalized crisp weight vector is:

    1 2( ', ',..., ')   nW w w w   (9)

    Step 4. Aggregate local priority weights into global priorities: the rank of each sub-criterion

    is calculated by multiplying its local weight with the corresponding local weights of

    subcriteria and criteria along the hierarchy. The global weights of criteria in the upper level

    hierarchy are equivalent to the local weights.

    In case of participation by two or more decision-makers, for each hierarchical level the

    evaluating process results in different comparison matrices, one for each decision-maker.

    Before applying the steps 1-4, it is then necessary to synthesize these in a single aggregate

    matrix, as follows (Chang, 1996; Wang and Elhag, 2007):

    If( ) ( ) ( ) ( )( , , )k k k k  ij ij ij ija l m u   (10)

    is the triangular fuzzy number which expresses the linguistic judgment provided by the k-th

    decision-maker (   1,...,

    k m ) and

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    ( ) 1

    ( ) ( ) ( )

    1 1 1( ) , ,

    k ij k k k 

    ij ij ij

    au m l 

     

      (11)

    is the reciprocal of( )k 

    ija . The average judgment, according to the fuzzy addition operation

    for TFNs (Kaufmann and Gupta, 1991) is:

    ( ) ( ) ( ) ( )

    1 1 1 1

    1 1 1 1, , , , 1,..., ;

    m m m mk k k k  

    ij ij ij ij ijk k k k  

    a a l m u i j n j im m m m

      (12)

    The previous aggregate matrix is then utilized as input in the steps 1-4.

    4. A case study of an Italian SME

    In this paper we apply the proposed fuzzy AHP method to the case of ACMO Group SpA, an

    Italian SME operating in design, manufacturing and consulting for water projects and

    hydraulic components. ACMO is certificated under ISO 14001:2000 (Environmental

    Management System) and ISO 9001:2008 (Quality Management Systems), indicating that the

    company is committed to corporate responsibility and deeply oriented towards its

    stakeholders. The direction of ACMO is interested in implementing appropriate reporting to

    further improve company accountability for performance in sustainability, but has never

     prepared a sustainability report, making this an ideal case to illustrate the proposed method.

    4.1 Implementing the fuzzy AHP method

    The process of defining the sustainability report content is carried out through face-to-face

    interviews with the expert decision-makers of the concerned company, particularly the top

    managers (GRI, 2013). When the company is an SME, it is especially important to engage the

    CEO in planning the content, because of his or her deep understanding of the company’s 

    organizational structure, processes and resources. In the case of ACMO, the interviews were

    conducted with the company owner, who is also CEO.

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    To begin the AHP procedure, the interviewee(s) must first be asked to judge the

    ‘applicability’ of all the GRI aspects and indicators (see Table 1), excluding those not

    suitable to the assessment of sustainability performance for that company. The reasons for the

    exclusions must later be explained in the sustainability report. In this case study, the company

    CEO judged all GRI aspects and indicators as applicable.

    Then, applying the three hierarchies (Figures 1, 2, 3), the interviewee is asked to express the

    relative ‘material’ importance of the GRI aspects by means of pair-wise comparisons, under

    the different sustainability dimensions of the analysis: the economic, environmental

    categories and social subcategories. Since the social hierarchy (Figure 3) includes the extra

    level of the social subcategories, for this hierarchy it is first necessary to compare the

    subcategories under the perspective of the broad social category before arriving at the still

    lower level of the GRI aspects.

    For brevity, Table 4 shows only the example of answers from ACMO’s CEO about the

    relative importance of the GRI aspects under the ‘Environmental’ category, where the GRI

    aspect of ‘Water’ is one of the terms of comparison. In the full implementation of the method,

    all the material GRI aspects must be evaluated in pair-wise comparisons: in the ACMO case

    there are a total of 12 material GRI aspects (Table 1) and 66 pair-wise comparisons. As an

    illustrative example, the first comparison of Table 4 is between the GRI aspects ‘Water ’ and

    ‘Materials’, applying the following question:

    -----------------------------------------------------

    INSERT TABLE 4 ABOUT HERE

    -----------------------------------------------------

    The respondent expresses the relative importance by means of linguistic terms (Table 4).

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    Once the GRI aspects are examined, the analysis proceeds with the evaluation of the relative

    importance of the GRI indicators. As an example, Table 5 shows the comparison between the

    GRI indicators under the ‘Water ’ aspect. The first comparison is between the GRI indicators

    G4-EN8 (total water withdrawal by source) and G4-EN9 (water sources significantly affected

     by withdrawal of water), applying the following question:

    < In the perspective of the GRI Aspect ‘Water’, to what extent is the indicator G4-EN8 more

    (or less) significant than the indicator G4-EN9 in describing, monitoring and analyzing the

    environmental sustainability performance of the company?>

    For brevity we again present only one table describing the comparison of the GRI indicators,

    however the fuzzy AHP method requires elaboration of a comparison table for each of the

    material GRI aspects considered (Table 1). In the ACMO case study, all GRI Aspects were

    deemed applicable and 46 tables were necessary.

    -----------------------------------------------------

    INSERT TABLE 5 ABOUT HERE

    -----------------------------------------------------

    As an example of collecting and elaborating the data, Table 6 shows the conversion of the

    Table 5 linguistic judgments into TFNs, applying the conversion scale in Table 2.

    -----------------------------------------------------

    INSERT TABLE 6 ABOUT HERE

    -----------------------------------------------------

    The fuzzy AHP method then continues, step by step.

    Step 1 . Using formula (3) the fuzzy comparison matrix (Table 6) is converted into a crisp

    comparison matrix (Table 7).

    -----------------------------------------------------

    INSERT TABLE 7 ABOUT HERE

    -----------------------------------------------------

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    Step 2. The consistency of the crisp matrix is analyzed: in this example the matrix (Table 7)

    is consistent with CI=0.034 and CR=0.06.

    Step 3. The row sum (6) and the normalized row sum (7) are calculated for each GRI

    indicator associated with a row of Table 7. In particular, the value of the row sum for the

    indicator G4-EN8 is calculated using (6) as follows:

    1   (1,1,1) (1,1.5,2) (0.33,0.4,0.5) (2.33,2.9,3.5) RS    

    The row sum values for the GRI indicators belonging to ‘Water’ are summarized in Table 8.

    -----------------------------------------------------

    INSERT TABLE 8 ABOUT HERE

    ---------------------------------------------

    The normalized row sum value for the indicator G4-EN8 is calculated utilizing (7) as follows:

    1 1 11

    1 1, 1 1, 1 1 1, 11

    2.33 2.9 3.5, , , ,1

    11.83 10.97 10.33

    (0.1969, 0.2644, 0.3388)

    n n n

    ij ij ij j j j

    n n n n n n n nn

    ij kj kj ij kj j j k k i j k j j k k i j j

    l m u RS 

    l u m u l   RS 

    S  

     

     

    The normalized row sum values for GRI indicators under ‘Water ’ are summarized in Table 9.

    ------------------------------------------------------

    INSERT TABLE 9 ABOUT HERE

    -----------------------------------------------------

    Then crisp weights are calculated using (8), and via normalization, the relative weights for

    the GRI Indicators belonging to ‘Water ’ are:

     

    The same procedure must be applied to all comparison matrices relative to the GRI aspects of

    the environmental category (see Figure 2).

    Step 4 . The overall results (global weights) of the ‘Environmental Category’ (Table 10) are

    obtained by multiplying the relative weights of the GRI aspects and indicators along the

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    hierarchy. For example, the global weight of G4-EN8 (2.6%) is obtained from multiplying

    the global weight of the ‘Water ’ aspect (10%) by the local weight of G4-EN8 (26%).

    -----------------------------------------------------

    INSERT TABLE 10 ABOUT HERE

    -----------------------------------------------------

    To complete the case study, the fuzzy AHP method is repeated for the GRI ‘Economic’ and

    ‘Social’ categories. The overall results are shown in the Appendix, Tables A.1, A.2, A.3.

    4.2 Results

    For brevity, we will discuss the results obtained for only one of the three categories of GRI

    sustainability reporting aspects. Figure 4 presents the global weights calculated for the

    environmental aspects (Table 10), for ACMO SpA. They express the relative materiality of

    the different GRI aspect in assessing the company’s sustainability performance in the

    environmental area. In this case, the most significant (material) GRI aspects are ‘Effluents

    and Waste’ (13%) and ‘Overall’ (11%). Slightly below this, with the equal scores of 10%, are

    ‘Materials’, ‘Water ’, ‘Emissions’, ‘Product and Services’  and ‘Supplier Environmental

    Assessment’. The ‘Compliance’  aspect receives the lowest score, and is thus the least

    significant for this company (4%).

    -----------------------------------------------------

    INSERT FIGURE 4 ABOUT HERE

    -----------------------------------------------------

    From the analysis, the CEO’s answers suggest that the most important factors in ACMO’s 

    environmental sustainability performance are the methods and management of water

    discharge and waste disposal (GRI aspect ‘Effluents and Waste’). ACMO’s commitment to

    reducing environmental impact is witnessed in the high weight for the GRI aspect ‘Overall’,

    which deals with expenditures on environmental protection. The fact that five further GRI

    aspects score a relative significance of 10% show that ACMO is uniformly committed to a

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    series of production practices for sustainability, corresponding to the GRI aspects concerning

    materials recycling, emissions reduction, mitigation of product and service impacts, and

    screening the supply chain. On the basis of these results, ACMO should focus its reporting on

    sustainability performance on all practices that enhance the company’s production efficiency

    and minimize environmental impacts, as indicated. These correspond to the specific GRI

    aspects: Effluents and Waste, Materials, Water, Emissions, Product and Services and

    Supplier Environmental Assessment.

    Figure 5 shows the ranking of the detailed GRI indicators entering under the above GRI

    aspects of the environmental category, again for the case of ACMO SpA.

    -----------------------------------------------------

    INSERT FIGURE 5 ABOUT HERE

    -----------------------------------------------------

    For example under aspect ‘Effluents and Waste’, the ACMO’s  CEO considers G4-EN22

    (‘total water discharge by quality and destination’, with relative significance 3.22%) as the

    GRI indicator most significant in describing the company water discharge performance.

    Reflecting this result, the section of the ACMO sustainability performance report dealing

    with the ‘Effluents and Waste’ aspect should stress indicator G4-EN22.

    The high relative importance given by ACMO’s CEO to the ‘Overall’ environmental aspect,

    and under this, G4-EN31 (total environmental protection expenditures and investments),

    means this is another indicator that should be described fully in the sustainability report.

    Under the environmental aspect of ‘Materials’, indicators G4-EN1 and G4-EN2 have the

    same relative importance. For this reason, ACMO’s sustainability report should describe both

    of these indicators with roughly the same emphasis and thoroughness, in order to capture the

    company sustainability performance with respect to the relatives subjects (material used for

     producing and packaging products and services; percentage of materials recycled). Among

    the indicators under the ‘Water ’ aspect, G4-EN10 is the most significant (5%) and

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    accordingly, for this aspect, ACMO’s sustainability report should focus on the percentage and

    total volume of water recycled and reused.

    Furthermore, to describe the environmental impacts related to ‘Emissions’, the ACMO’s 

    CEO considers G4-EN19 (reduction of greenhouse gas emissions) as the most important

    (1.9%) of the seven possible indicators for reporting. This ranking in fact reflects the

    subjective opinion of the CEO, who stresses that the company takes a proactive attitude

    concerning the reduction of greenhouse gases resulting from its productive processes.

    To monitor sustainability performance under ‘Product and Services’, the identification of

    ‘extent of impact mitigation of environmental impacts of products and services’ (G4-EN27)

    is more relevant than the other possible indicator, of ‘ percentage of products sold and their

     packaging materials that are reclaimed’ (G4-EN28). The company CEO considers the first

    indicator (G4-EN27) as more significant, because it allows describing the impact of products

    and services in a more comprehensive way.

    In terms of the aspect ‘Supplier environmental assessment’, there are two possible indicators.

    Here, the ACMO’s CEO has indicated G4-EN32 (percentage of new suppliers screened using

    environmental criteria) as more important than G4-EN33, which reports on series of impacts

    involving the company supply chain and actions. Based on these results, it appears that the

    CEO considers new suppliers as presenting important risks and possibilities for sustainability

    action, making reporting on their screening more significant than reviewing the entire chain.

    Figure 5 also shows the ranking of the remaining indicators, for the GRI aspects of the

    environmental category that ACMO’s CEO considers of lesser significance.

    The company should use the outcomes from the fuzzy AHP method (as summarized in Figure

    5 for the environmental category) to achieve more effective and efficient sustainability

    reporting. By focusing on the most significant aspects and indicators, as indicated by the

    analyses for all three GRI categories, ACMO can focus its sustainability reporting on topics

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    material to its business and stakeholders. It can achieve reports that matter, containing

    information about its most critical sustainability issues, while spending less resources in time,

    money and expertise to carry out the actual reporting tasks.

    5. Managerial implications for sustainability reporting

    The proposed fuzzy AHP method offers a guide to companies in identifying the appropriate

    content for preparation of their sustainability reports, in terms of the priority to place on the

    different GRI ‘Aspects’  and ‘Indicators’. The fuzzy AHP method indicates the relative

    importance of the different aspects and their indicators in assessing company performance. In

    keeping with the GRI reporting guidelines, each aspect must be described with a level of

    accuracy corresponding to its level of importance. The most significant aspects should be

    analyzed not only in qualitative terms, but also through presentation of quantitative

    information. Under the GRI aspects, the prioritization of the indicators using fuzzy AHP

    identifies the more suitable ones to report the sustainability performance for the issues of

    concern. The higher is the relative importance of an indicator, the more attention should be

     paid to its reporting, for example through analysis of quantitative information, time series and

    trends.

    For instance in the case study of the SME, ACMO SpA, the fuzzy AHP analysis points to

    G4-EN22 as the highest priority indicator under the ‘Effluents and Waste’ aspect. In

    reporting on this aspect, ACMO would then be advised to disclose detailed information on

    G4-EN22, for example enumerating the total volume of water discharges by destination and

    over different periods, as well as giving the procedures for these calculations. However for

    the same GRI aspect, G4-EN24 is less significant than G4-EN22, and in this case ACMO can

    report in less detail: for example disclosing preventive measures, or identifying the number

    and volume of spills should any occur over the reporting period.

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    The proposed fuzzy AHP method also serves in planning performance reporting in a further

    way. In particular, it permits the company to identify of a threshold percentage of

    significance, below which it will consider GRI indicators or the higher level of aspects as

    ‘immaterial’, or irrelevant to sustainability reporting. For this purpose, we define the variable

    ‘Completeness’ that is calculated as the sum of the global weights of all the indicators whose

    level of priority is greater than or equal to the one considered. For example in the ACMO

    case, referring to Figure 5, the indicators whose global weights are to be summed are the ones

    on the left of the indicator under analysis, plus that indicator itself. The priority levels for the

    indicators are established applying two rankings. The first is on the basis of the aspect

    ranking: continuing the example of Figure 5, the ‘Water’ aspect ranks higher than

    ‘Emissions’, therefore the group of ‘Water ’ indicators score higher in priority than those for

    ‘Emissions’. Second, the indicators are ranked within their aspect: again in Figure 5, among

    the group of ‘Water ’  indicators, G4-EN10 has a higher priority than G4-EN8. Examining

    Figure 5, we see that ACMO could choose to achieve a level of Completeness of

    approximately 81%, which would be accomplished by selecting GRI indicator G4-EN30 and

    all the indicators and aspects to its left. As described in the paragraphs above, the company

    would then report on the selected material aspects and indicators with a level of accuracy

    corresponding to the level of priority (significance).

    For ACMO, all GRI indicators and aspects with a level of priority lower than that of G4-

    EN30 would then be ‘not relevant’  (immaterial). These would not be described in the

    sustainability report, instead being noted only with a short explanation of omission. For

    example, the lowest ranked GRI aspect is ‘Compliance’, which deals with fines and sanctions

    for non-compliance to environmental laws and regulations. In subjective opinion, the

    ACMO’s  CEO considers the fact that the company is free of sanctions as not relevant in

    reporting sustainability performance, because the Italian water technology industry is in any

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    case characterized by very low frequency of sanctions for environmental violations.

    Similarly, at the level of the indicators under ‘Compliance’, G4-EN29 (total numbers of fines,

    sanctions, cases subjected to resolution) is deemed not relevant to describing ACMO SpA’s

    sustainability performance.

    Obviously, the maximum level of Completeness in sustainability reporting (100%) could be

    obtained by detailing all GRI aspects and indicators. However, higher levels of Completeness

    require that the company commit to engaging greater resources in the implementation of

    reporting. The ex-ante choice of a level of engagement is particularly important in the case of

    companies with limited resources, such as is typical for SMEs. In this regard, the fuzzy AHP

    method offers a tool to assist SMEs in planning reporting levels, and then further tools to

    obtain properly balanced reporting on the ‘material’ aspects and indicators, thus optimizing

    the time and resources needed to collect the information for disclosing the company

    sustainability performance.

    6. Conclusions

    The purpose of a company’s sustainability report is to disclose information on its critical

    economic, environmental and social impacts. Reporting on sustainability performance must

    disclose appropriate levels of information on those aspects that are truly affected by company

    activities, because not all sustainability issues have the same relevance for every company

    (ISO, 26000; GRI, 2013a, 2013b). The current paper presents a fuzzy AHP method that

    supports companies in the identification of the most appropriate areas and levels of content to

     be included in their sustainability reports.

    The method involves face-to-face interviews with the company’s expert decision-makers

    (CEO, top managers) to collect linguistic judgments that feed in to a specifically developed

    fuzzy AHP method. The method deals with the imprecision and ambiguity typical of

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    linguistic judgments, and elaborates them to support informed decision-making in the

     planning of sustainability reporting. The paper presents a case study to illustrate the

    implementation of the method, applied to an Italian SME operating in the water technology

    industry.

    The method is based on the G4 GRI Sustainability Reporting Guidelines. It prioritizes the

    GRI aspects and indicators in terms of their significance for reporting the company’s 

    sustainability performance. The level of priority of each aspect or indicator is used to identify

    the type and degree of detail necessary for the sustainability report (e.g. quantitative

    information, time series, trends). Using the fuzzy AHP method, company managers also

    define a threshold of significance, below which GRI aspects and indicators will be excluded

    from reporting, due not being relevant (not ‘material’).

    The ex-ante choice of a level of completeness is particularly important for companies with

    limited resources to dedicate to reporting activities, such as is typical for SMEs. The

     proposed fuzzy AHP method is a tool that can assist SMEs in their sustainability reporting,

     by focusing and reducing the tasks of data collection and report preparation. The method

    makes sustainability reporting more feasible for the many SMEs that do not yet provide

    formal, fully-structured reports. For those companies engaged in sustainability reporting, the

    method serves to improve relevance and precision, while containing costs in terms of time

    and resources.

    Acknowledgments

    We especially thank Paolo Sebastiani (ACMO’s CEO) and Costanza Sebastiani  for their

    contribution in the realization of the case study.

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    References

    Adams, C.A., 2002. Internal organizational factors influencing corporate social and ethical

    reporting: beyond current theorizing. Accounting, Auditing & Accountability Journal,

    15(2), 223-50.

    Alonso, J.A., Lamata M.T., 2006. Consistency in the analytic hierarchy process: a newapproach. International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems,

    14(4), 445−459. 

    Arena, M., Azzone, G., 2012. A process-based operational framework for sustainability

    reporting in SMEs. Journal of Small Business and Enterprise Development , 19(4), 669-

    686.

    Baumann-Pauly, D., Wickert, C., Spence, L.J., Scherer, A.G., 2013. Organizing corporate

    social responsibility in small and large firms: size matters. Journal of Business

    Ethics , 115(4), 693-705.

    Bebbington, J., 2001, June. Sustainable development: a review of the international

    development, business and accounting literature. Accounting Forum, 25 (2), 128-157.

    Blackwell Publishers Ltd.Belal, A.R., Cooper, S., 2011. The absence of corporate social responsibility reporting in

    Bangladesh. Critical Perspectives on Accounting, 22(7), 654-667.

    Birth, G., Illia, L., Lurati, F., Zamparini, A., 2008. Communicating CSR: practices among

    Switzerland's top 300 companies. Corporate Communications: An International

    Journal, 13(2), 182-196.

    Bouten, L., Everaert, P., Van Liedekerke, L., De Moor, L., Christiaens, J., 2011, September.

    Corporate social responsibility reporting: a comprehensive picture?. Accounting

    Forum, 35 (3), 187-204.

    Brown, H.S., de Jong, M., Levy, D.L., 2009. Building institutions based on information

    disclosure: lessons from GRI's sustainability reporting. Journal of Cleaner

    Production, 17(6), 571-580.Burritt, R. L., Schaltegger, S., 2010. Sustainability accounting and reporting: fad or

    trend?. Accounting, Auditing & Accountability Journal, 23(7), 829-846.

    Calabrese, A., Costa, R., Menichini, T., 2013a. Using fuzzy AHP to manage intellectual

    capital assets: an application to the ICT service industry. Expert Systems with

    Applications, 40(9), 3747-3755.

    Calabrese, A., Costa, R., Menichini, T., Rosati, F., 2013b. Does corporate social

    responsibility hit the mark? A stakeholder oriented methodology for CSR

    assessment. Knowledge and Process Management, 20(2), 77-89.

    Chang, D.Y., 1996. Application of extend analysis method on fuzzy AHP. European Journal

    of Operational Research , 95(3), 649-655.

    Chen, S., Fan, J., 2011. Measuring corporate social responsibility based on a fuzzy analyticalhierarchy process. I.J. Computer Network and Information Security, 5, 13-22.

    Csutora, R., Buckley, J.J., 2001. Fuzzy hierarchical analysis: the Lambda-Max

    method. Fuzzy sets and Systems , 120(2), 181-195.

    Dawkins, C., Ngunjiri, F.W., 2008. Corporate social responsibility reporting in South Africa,

    a descriptive and comparative analysis. Journal of Business Communication, 45(3), 286-

    307.

    Deegan, C., 2002. Introduction: the legitimising effect of social and environmental

    disclosures – a theoretical foundation. Accounting, Auditing & Accountability

    Journal, 15(3), 282-311.Forman, E.H., 1990. Random indices for Incomplete Pairwise Comparison Matrices.

    European Journal of Operational Research , 48(1), 153-155.

  • 8/18/2019 A Fuzzy AHP Method to Support Sustainability Reporting an Application to the Water Technology

    31/50

    1

    2

    3

    4

    5

    67

    8

    9

    10

    11

    12

    13

    14

    15

    16

    17

    18

    1920

    21

    22

    23

    24

    25

    26

    27

    28

    29

    30

    31

    32

    33

    34

    35

    36

    37

    38

    39

    40

    41

    42

    43

    44

    45

    46

    47

    48

    49

    50

    51

    52

    53

    54

    55

    56

    57

    58

    59

    60

    61

    62

    63

    64

    65

    27

    Fortanier, F., Kolk, A., Pinkse, J., 2011. Harmonization in CSR reporting. Management

    International Review, 51(5), 665-696.

    Gamerschlag, R., Möller, K., Verbeeten, F., 2011. Determinants of voluntary CSR disclosure:

    empirical evidence from Germany. Review of Managerial Science, 5, 233-262.

    GRI-Global Reporting Initiative, 2006. G3.1, Sustainability Reporting Guidelines, available

    at: www.globalreporting.org GRI-Global Reporting Initiative (2013a). G4, Part1, Reporting Principles and Standard

    Disclosure, available at: www.globalreporting.org. 

    GRI-Global Reporting Initiative (2013b). G4, Part2, Implementation Manual,

    available at: www.globalreporting.org. 

    GRI-Global Reporting Initiative, 2013c. Sustainability Reporting Policies Worldwide,

    available at: www.globalreporting.org. 

    Hahn, R., Kühnen, M., 2013. Determinants of sustainability reporting: a review of results,

    trends, theory, and opportunities in an expanding field of research. Journal of Cleaner

    Production, 59, 5-21.

    Herzig, C., Schaltegger, S., 2011. Corporate sustainability reporting, in: Godemann J.,

    Michelsen G. (Eds.), Sustainability Communication. Springer, Netherlands, pp.151-169.

    Hooghiemstra, R., 2000. Corporate communication and impression management: new

     perspectives why companies engage in corporate social reporting. Journal of Business

    Ethics, 27(1-2), 55-68.

    Hsu, C.W., Lee, W.H., Chao, W.C., 2013. Materiality analysis model in sustainability

    reporting: a case study at Lite-On Technology Corporation. Journal of Cleaner

    Production, 57, 142-151.

    Huang, C.C., Chu, P.Y., Chiang, Y.H., 2008. A fuzzy AHP application in government-

    sponsored R&D project selection. Omega, 36(6), 1038-1052.

    ISO - International Organization for Standardization, 2010. Guidance on Social

    Responsibility - ISO 26000:2010(E). Geneva.Kaufmann, A., Gupta, M.M., 1991. Introduction to Fuzzy Arithmetic: Theory and

    Applications, VanNostrand Reinhold, New York.

    Koerber, C.P., 2010. Corporate responsibility standards: current implications and future

     possibilities for peace through commerce. Journal of Business Ethics , 89, 461-480.

    Kolk, A., 2005. Sustainability reporting. VBA Journal , 21(3), 34-42.

    Kolk, A., 2008. Sustainability, accountability and corporate governance: exploring

    multinationals' reporting practices. Business Strategy and the Environment, 17(1), 1-15.

    Krajnc, D., Glavič, P., 2005. How to compare companies on relevant dimensions of

    sustainability. Ecological Economics , 55(4), 551-563.

    Kwong, C.K., Bai, H., 2003. Determining the importance weights for the customer

    requirements in QFD using a fuzzy AHP with an extent analysis approach. IIETransactions, 35(7), 619-626.

    Lee, S.H., 2010. Using fuzzy AHP to develop intellectual capital evaluation model for

    assessing their performance contribution in a university. Expert Systems with

    Applications, 37(7), 4941-4947.

    Lepoutre, J., Heene, A., 2006. Investigating the impact of firm size on small business social

    responsibility: a critical review. Journal of Business Ethics, 67(3), 257-273.

    Ligteringen, E., Zadek, S., 2005. The future of corporate responsibility codes, standards and

    frameworks, available at: www.globalreporting.org. 

    Lozano, R., 2013. Sustainability inter-linkages in reporting vindicated: a study of European

    companies. Journal of Cleaner Production, 51, 57-65.

    Lozano, R., Huisingh, D., 2011. Inter-linking issues and dimensions in sustainabilityreporting. Journal of Cleaner Production, 19(2), 99-107.

    http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/http://www.globalreporting.org/

  • 8/18/2019 A Fuzzy AHP Method to Support Sustainability Reporting an Application to the Water Technology

    32/50

    1

    2

    3

    4

    5

    67

    8

    9

    10

    11

    12

    13

    14

    15

    16

    17

    18

    1920

    21

    22

    23

    24

    25

    26

    27

    28

    29

    30

    31

    32

    33

    34

    35

    36

    37

    38

    39

    40

    41

    42

    43

    44

    45

    46

    47

    48

    49

    50

    51

    52

    53

    54

    55

    56

    57

    58

    59

    60

    61

    62

    63

    64

    65

    28

    Mahoney, L.S., Thorne, L., Cecil, L., LaGore, W., 2013. A research note on standalone

    corporate social responsibility reports: signaling or greenwashing?. Critical Perspectives

    on Accounting, 24(4), 350-359.

    Marimon, F., Alonso-Almeida, M.D.M., Rodríguez, M.D.P., Cortez Alejandro, K.A., 2012.

    The worldwide diffusion of the global reporting initiative: what is the point?. Journal of

    Cleaner Production, 33, 132-144.Meyskens, M., Paul, K., 2010. The evolution of corporate social reporting practices in

    Mexico. Journal of Business Ethics, 91(2), 211-227.

    Porter, M.E., Kramer, M.R., 2006. Strategy and society: the link between competitive

    advantage and corporate social responsibility. Harvard Business Review, 84(12), 78-92.

    Porter, M.E., Kramer, M.R., 2011. Creating shared value. Harvard Business Review , 89(1/2),

    62-77.

    Robinson, J., 2004. Squaring the circle? Some thoughts on the idea of sustainable

    development. Ecological Economics, 48(4), 369-384.

    Saaty, T.L., 1980. The Analytic Hierarchy Process , McGraw-Hill, New York.

    Schadewitz, H., Niskala, M., 2010. Communication via responsibility reporting and its effect

    on firm value in Finland. Corporate Social Responsibility and Environmental

    Management , 17, 96-106.

    Schmeltz, L., 2014. Introducing value-based framing as a strategy for communicating

    CSR. Social Responsibility Journal, 10(1), 184-206.

    Wang, Y.M., Elhag, T.M.S., 2007. A fuzzy group decision making approach for bridge risk

    assessment. Computer & Industrial engineering , 53(1) , 137-148.

    Wang, Y.M., Luo, Y., Hua, Z., 2008. On the extent analysis method for fuzzy AHP and its

    applications. European Journal of Operational Research , 186 (2), 735-747.

    Yager, R.R., 1981. A procedure for ordering fuzzy subsets of unit interval. Information

    Sciences, 24, 143-161. 

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    Figure 1: Hierarchical structure of GRI aspects and indicators of the economic category.

    Assessing the significance of GRI aspects and indicators of the economic category

    EconomicPerformance

    G4-EC1

    G4-EC2

    G4-EC3

    G4-EN4

    Market Presence

    G4-EC5

    G4-EC6

    Indirect EconomicImpacts

    G4-EC7

    G4-EC8

    Procurement Practices

    G4-EC9

    re

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    Figure 2: Hierarchical structure of GRI aspects and indicators of the environmental category.

    Assessing the significance of GRI aspects and indicators of the environmental category

    Materials 

    G4-EN1

    G4-EN2

    Energy

    G4-EN3

    G4-EN4

    G4-EN5

    G4-EN6

    G4-EN7

    Water 

    G4-EN8

    G4-EN9

    G4-EN10

    Biodiversity 

    G4-EN11

    G4-EN12

    G4-EN13

    G4-EN14

    Emissions

    G4-EN15

    G4-EN16

    G4-EN17

    G4-EN18

    G4-EN19

    G4-EN20

    G4-EN21

    Effluents andWaste

    G4-EN22

    G4-EN23

    G4-EN24

    G4-EN25

    G4-EN26

    Products andServices

    G4-EN27

    G4-EN28

    Compliance

    G4-EN29

    Transport

    G4-EN30

    Overall

    G4-EN31

    SupplierEnvironmental

    Assessment

    G4-EN32

    G4-EN33

    EnvironmentalGrievance

    Mechanisms

    G4-EN34

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    Figure 3: Hierarchical structure of GRI aspects and indicators of the social category.

    Assessing the significance of GRI aspects and indicators of the social category 

    Labor Practicesand Decent Work  

    Employment 

    Labor ManagementRelations 

    Occupational Healthand Safety 

    Training andeducation 

    Diversity and

    Equal Opportunity 

    Equal Remunerationfor Women and Men 

    Supplier Assessment

    for Labor Practices 

    Labor PracticesGrievance

    Mechanisms

    Human Rights 

    Investment 

    Non-discrimination 

    Freedom of

    Association andCollective argaining

    Child Labor

    Forced andCompulsoryLabor 

    SecurityPractices 

    IndigenousRights 

    Assessment 

    Human RightsGrievanceMechanisms 

    Supplier HumanRights Assessment

    Society 

    Local

    Communities 

    Anti-Corruption 

    Public Policy 

    Anti-competitiveBehavior 

    Compliance 

    Supplier Assessment

    for Impacts on Society 

    Grievance

    Mechanisms

    for Impacts on Society 

    Product Responsibility 

    Customer Healthand Safety 

    Product andService Labeling 

    MarketingCommunications 

    CustomerPrivacy 

    Compliance 

    G4-LA1G4-LA2 

    G4-LA3 

    G4-LA4

    G4-LA5

    G4-LA6 G4-LA7

    G4-LA8 

    G4-LA9

    G4-LA10 

    G4-LA11 

    G4-LA12

    G4-LA13

    G4-LA14G4-LA15 

    G4-HR1

    G4- HR2 

    G4-HR3

    G4-HR4

    G4-HR5

    G4-HR6

    G4-HR7

    G4-HR8

    G4-HR9

    G4-HR10

    G4- HR11 

    G4-HR12

    G4-SO1G4- SO2 

    G4-SO3G4-SO4

    G4-SO5

    G4-SO6

    G4-SO7

    G4-SO8

    G4-SO9

    G4-SO10

    G4-SO11

    G4-PR1G4- PR2 

    G4-PR3G4-PR4

    G4-PR5

    G4-PR6G4-PR7

    G4-PR8

    G4-PR9

    G4-LA16

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    Figure 4: Level of significance (materiality) of GRI aspects under the environmental category.

    10%

    5%

    10%

    5%

    10%

    13%10%

    4%

    7%

    11%

    10%

    5%

    Materials

    Energy

    Water

    Biodiversity

    Emissions

    Effluents and Waste

    Products andServices

    Compliance

    Transport

    Overall

    Supplier

    EnvironmentalAssessment

    EnvironmentalGrievance

    Mechanisms

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    Environmental Aspect Description Environmental Aspect Description

    ENA1 Effluents and Waste ENA7 Supplier Environmental Assessment

    ENA2 Overall ENA8 Transport

    ENA3 Materials ENA9 Energy

    ENA4 Water ENA10 Biodiversity

    ENA5 Emissions ENA11 Environmental Grievance Mechanisms