Abstract
In this study, an intelligent approach is presented for the evaluation and selection of innovation projects. Selecting the best innovation project is a complicated multiple criteria decision making (MCDM) problem with several potentially competing quantitative and qualitative criteria. In this paper, two hesitant fuzzy MCDM methods; hesitant fuzzy Analytic Hierarchy Process (hesitant F-AHP) and hesitant fuzzy VIsekriterijumska optimizacija i KOmpromisno Resenje (hesitant F-VIKOR) are integrated to evaluate and rank innovation projects. In the hesitant fuzzy AHP-VIKOR, hesitant F-AHP is used to find fuzzy evaluation criteria weights and hesitant F-VIKOR is implemented to rank innovation project alternatives. A numerical example is given where five innovation projects are evaluated based on nine criteria by three decision makers.
Introduction
In today’s business environment, innovation has been a critical point for companies under fierce world competition. With the effect of globalization winds, companies are increasingly forced to design and manufacture more innovative products, and compete with their competitors in national, as well as international level since consumers demand more sophisticated and innovative products [61]. On the other hand, innovation studies help strengthen the economies with a sustainable growth and prevent the economic crises [33]. As a result of this, most companies invest more sources in innovation studies to develop their competitive advantage (i.e. increasing market share and productivity), by spending on around 1-2% of turnover on innovation activities.
A recent global survey by the BCG on innovation practices in companies, reveals that innovation is one of their company’s top-three priorities [2]. Moreover, in near future, around 60% of companies plan to increase their innovation spending [2]. Spending on innovation-related activities are also encouraged by governments in various ways: for instance; implementing policies to stimulate R&D projects directly through grants or loans [33]. R&D projects are main elements of innovation and they help improve competitive advantage [18]. Hence, government funding and support of innovation projects by assisting companies results in designing and manufacturing more innovative products and better financial performance [47].
An intelligent method is needed to evaluate and prioritize innovation projects, especially when there are several competing qualitative and quantitative criteria to consider in the evaluation. In this research, an intelligent MCDM method is presented to evaluate innovation projects at the beginning stages of innovation in a context of limited resources. As the MCDM method, hesitant F-AHP and hesitant F-VIKOR are integrated. In hesitant fuzzy AHP-VIKOR, hesitant F-AHP is used to determine the fuzzy weights of the evaluation criteria since with hesitant F-AHP, using pairwise comparisons of both quantitative and qualitative criteria, dependable weights can be determined. However, when there are many alternatives and criteria, hesitant F-AHP, without the integration, can be tiresome since a great deal of pairwise comparisons are needed. Therefore, hesitant F-VIKOR is employed to evaluate alternatives, using the obtained fuzzy criteria weights. Hesitant F-VIKOR does not provide guidelines to determine criteria weights, so a reliable method such as hesitant F-AHP is needed in this integration.
AHP, introduced by Saaty in 1980 s [42], has a hierarchical and multi-level structure. In AHP, alternatives are evaluated based on various criteria and then ranked according to a total weighted score. VIKOR is mostly for problems with competing or non-commensurable criteria. In VIKOR, compromise ranking is performed between alternatives based on closeness to the ideal solution [36, 52]. To capture the uncertainty and vagueness on judgments of decision-makers (DMs), their fuzzy extensions, F-AHP and F-VIKOR and integrated fuzzy AHP-VIKOR have been used in many MCDM problems in the literature. F-VIKOR is broadly used to find compromise solution(s) to problems with many alternatives and conflicting criteria. With F-VIKOR, an established compromise solution is determined with a maximum group utility of the majority and a minimum of individual regret of the opponent [23, 35–38].
Traditional fuzzy AHP-VIKOR integration has been used in several applications in the literature such as public transportation bus selection [7], tyre recycling process selection [42], renewable energy and production site selection in Istanbul [19], material selection for pipes in sugar industry [1], fiscal performance evaluation of Iranian companies [14], manufacturing machine tool selection [16], biodiesel blend selection for IC engines [37], compliant polishing tool selection [2], the best knowledge flow practicing organization selection [8], evaluation of sectoral investments for sustainable development [46], quantifying risk ratings in occupational health and safety risk assessment [16] and selection of sustainable energy conversion technologies for agricultural residues [54]. In traditional F-AHP and F-VIKOR, DMs give a single linguistic expression to evaluate criteria and alternatives, respectively. However, this does not reflect the degrees of hesitation DMs might have in reality. For example, while evaluating an alternative with respect to a criterion in F-VIKOR, a DM might want to asses as “this alternative’s performance is between fair and medium good with respect to the considered criterion”. In this research, to allow these kind of “hesitant” expressions, to enrich the evaluation linguistic expressions and to represent the opinions of DMs more accurately in a more flexible manner, hesitant fuzzy linguistic term sets (HFLTS) are employed in fuzzy AHP-VIKOR.
The concept of hesitant fuzzy sets and HFLTS were introduced by Torra and Narukawa [49] and Rodrigez et al. [41] and in HFLTS, multi-linguistic expressions can be considered with linguistic variables. Usage of HFLTS in decision making improves the flexibility and enriches the multiple linguistic evaluations [22]. In the literature, HFLTS are used in a few applications. Tüysüz and Şimşek [50] developed a hesitant F-AHP to analyse and prioritize the factors affecting the performance of a cargo company in Turkey. Umamaheswari and Kumari [53] implemented triangular hesitant fuzzy sets in F-TOPSIS and F-VIKOR and presented a numerical example about teacher quality evaluation. Öztayşi et al. [39] developed a hesitant F-AHP and used it for supplier selection. Ayhan [6] applied hesitant F-AHP to determine criteria weights and then TOPSIS to evaluate and rank summer sport schools. Başar [9] used hesitant fuzzy pairwise comparisons for software cost estimation in a Turkish company. Dong et al. [14] developed a linguistic hesitant F-VIKOR approach and presented an intelligent transportation system evaluation example to demonstrate the effectiveness of the approach. Li et al. [22] implemented hesitant F-AHP to determine weights of criteria and then F-VIKOR to rank power generation enterprises. Camci et al. [12] applied hesitant F-AHP to select CNC router in small and medium-sized enterprises in woodwork manufacturing. Acar et al. [1] implemented hesitant F-AHP to evaluate sustainability of different hydrogen production methods. Narayanamoorthy et al. [32] used interval-valued intuitionistic hesitant fuzzy entropy based VIKOR for selection of industrial robots and presented a numerical example related to a material handling operation.
At present, there does not appear to be a research paper in the literature about the integration of hesitant F-AHP and hesitant F-VIKOR, and its application to evaluation of innovation projects. With the proposed hesitant fuzzy AHP-VIKOR, innovation projects are evaluated and ranked without too many tiresome pairwise comparisons and complex calculations. The MCDM literature related to project selection is given in Section 2 and steps of hesitant fuzzy AHP-VIKOR are explained in Section 3. In Section 4, a numerical example is given to explain the steps further, along with conclusions in Section 5.
Literature review
In the literature, there are many methods used for project selection [55]. Badri et al. [7] made a list of methods that are used for information system project selection problem. Dey [13] also listed project selection methods such as; fuzzy logic, GP with LP and AHP. Various kinds of project selection methods and corresponding decision problems can be found in Wang et al.’s research [55]. Wang et al. [55] also compared project selection methods such as cost analysis, linear and integer programming, fuzzy logic, AHP, ANP and Grey Target Decision in terms of their advantages and disadvantages.
Specifically, innovation project selection has been studied in various research papers. Mikkola [30] used an R & D Project Portfolio matrix that links the company’s competitive advantages to the benefits of projects to its customers and analyzed the portfolios of R & D projects, as an example, demonstrating battery samples for electric vehicles and hybrid electric vehicles. Melon et al. [29] implemented AHP to evaluate educational innovation projects for the Institute of Educational Sciences of the Politechnical University of Valencia. Zimmer, Yannou and Stal-Le Cardinal [60], as one of the foundations of radical innovation design methodology, created a selection model that measures innovative ideas, concepts or projects according to evidence of value, concept and innovation and they used this model in an innovation competition about development of new products and elderly services. Lerch and Spieth [21] worked on the cause-effect of innovation project portfolio management (IPPM) performance and have shown that performance should be considered as an integrated system consisting of portfolio balance, strategic compliance and value maximization, simultaneously. Later, Spieth and Lerch [45] tested hypotheses on the use of methods, the use of criteria, the IPPM design, the existence of knowledge, and the interactions between internal perceptions on management perception and satisfaction, and on IPPM performance and innovation. As a result, the methods and criteria are determined to have an insignificant role, however IPPM design elements such as transparency and formality are found to be the key elements in IPPM performance. They also determined that the existence of knowledge and management perception and satisfaction are key structures in IPPM performance. Mitchell, Phaal and Athanassopoulou [31] presented a multi-factor scoring system design approach to evaluate and select early stage innovation projects. Brook and Pagnanelli [11] focused on the automotive industry and prioritized the innovation projects. First, they determined the weights of AHP and then with the weighted average technique SMART, they calculated the total values of the projects with and prioritized the projects according to these values. Bin et al. [10] used a two-phase method for the selection of R & D and innovation projects in the Brazilian electricity sector, solving a backpack problem in the first phase, choosing projects that would provide the greatest benefit considering the limited resources, and then sorting these projects using the PROMETHEE II method. Barcic et al. [8] deconstructed innovation in the Croatian furniture industry to three components: product innovation, process innovation, human resource innovation. Then they evaluated the relationship between these components and 4 company management activities / factors (R & D investments, company flexibility, export activity and internet use). The links between innovation components and business practices have revealed the importance of management activities in the furniture industry for innovation studies and development. Meifort [28] conducted a large literature review on innovation portfolio management and discussed the study in 4 perspectives: the perspective of optimization, strategic perspective, decision-making perspective and organizational perspective. Rathi et al. [40] used F-VIKOR to evaluate and prioritize six sigma projects in the Indian auto sector. Lin et al. [24] evaluated the critical success factors affecting project execution, integrating F-AHP and VIKOR. In their research, first F-AHP was used to determine weights and then VIKOR was used to rank factors in environmental consultancy service industry in Taiwan. He and Xu [17] implemented three MCDM methods: the probabilistic hesitant fuzzy reference ideal method (PHFRIM), the technique for order preference by similarity to a reference ideal solution (TOPSRIS) and the reference ideal VIKOR (RI-VIKOR) to the total dissolved gas evaluation problem of water conservancy projects and made a comparison analysis.
To the best of authors knowledge, in the literature, fuzzy AHP-VIKOR or hesitant fuzzy AHP-VIKOR methods have never been applied to an innovation project selection problem. Next, the steps of the proposed approach; hesitant fuzzy AHP-VIKOR are explained more in detail.
Hesitant fuzzy AHP-VIKOR Approach
Definitions
In fuzzy set theory, there are classes with unsharp boundaries [20, 27] and crisp theories can be fuzzified by applying the concept of a fuzzy set [59] to the set within that theory. In the proposed hesitant fuzzy AHP-VIKOR approach, triangular fuzzy numbers (TFNs) are utilized due to its simplicity. A fuzzy number is a special fuzzy set F ={ (x, μ
F
(x)) , x ∈ R } where x is a real number, R : -∞ < x < + ∞ and μ
F
(x) is a continuous mapping from R to [0, 1]. A TFN denoted as
Basic operations between two positive TFNs
As the defuzzification method of TFNs, the graded mean integration approach [57] is used as seen below:
In determining the membership degree of an element, a DM might hesitate while making judgements since there may be more than one possible value. The concept of hesitant fuzzy sets (HFS) was introduced to address this problem [48, 49]. In Triangular Fuzzy Hesitant Fuzzy Sets (TFHFS), the membership degree of an element to a given set is expressed by several possible TFNs. In the literature, several aggregation operators for TFHFS were proposed by Yu [58] and Yu applied these concepts to a teaching quality evaluation problem.
If X is a fixed set, the HFS on X returns a subset of [0, 1] by: devendran
where h
E
(x)is the possible membership degrees of element x ∈ Xto set E by taking values in [0, 1]. The lower and upper bounds are calculated as:
Basic operations for 3 HFS h, h1, h2 are as follows:
An Ordered Weighting Averaging (OWA) operator that can be used in the process is as follows:
DM evaluations are combined by fuzzy envelope approach [26] in hesitant F-AHP and hesitant F-VIKOR steps. Scales given for DM evaluations are sorted from the lowest s o to the highest s g so if the DM’s evaluations are between s i and s j , then s o ≤ s i ≤ s j ≤ s g .
Based on the hesitant fuzzy linguistic term sets, linguistic expressions can be represented by a triangular fuzzy membership function
Weight vector in OWA operator is defined in Filev and Yager’s [15] research as:
Here, g depends on the number of terms in DM’s evaluation scale (in Table 1 or Table 2), j is the rank of the highest, and i is the rank of the lowest evaluation value. i and j can take ranks starting from 0 to g and n = j-i. [9]
Scale for the evaluation of criteria in hesitant F-AHP [44]
Scale for the ratings of alternatives in hesitant F-VIKOR [44]
In hesitant F-AHP, the DMs make pairwise comparisons of criteria to determine the fuzzy importance weights using the linguistic terms given in Table 1.
Computational Steps of F-AHP: [3–5, 43]
Step 1: Identify K DMs, n criteria; and linguistic terms and scale for the pairwise comparison of criteria. Based on the scale used in Table 1 and Equations (23)-(27), combine DM’s evaluations with fuzzy envelope approach and obtain TFNs corresponding to the evaluation of each DM. Calculate
Step 2:
Step 3:
The consistency index (CI) is calculated as:
The consistency ratio (CR) in Equation (30) is used to estimate the consistency of pairwise comparisons.
RI is the average index for randomly generated weights [42]. If CR < 0.10, the comparisons are acceptable, otherwise they are not [42].
After finding
Computational Steps of hesitant F-VIKOR: [19, 56]
Step 1: Identify m alternatives; and linguistic terms for the evaluations of alternatives with respect to each criterion.
Based on the scale used in Table 2 and Equations (23)-(27), combine DM’s evaluations with fuzzy envelope approach and obtain TFNs corresponding to the evaluation of each DM. Calculate
where
Step 2: Determine the fuzzy best value (FBV,
Step 3: Calculate the separation measures of each alternative from the FBV (
Step 4: Calculate
Step 5: Calculate
Here, ν is the weight of the strategy of the maximum group utility (majority of criteria) and 1 - ν is the weight of the individual regret. ν is usually assumed to be 0.5 (by consensus). [3, 19].
Step 6: Defuzzify the
In this study, 9 criteria (C1, C2, ... , C9) are determined for the evaluation of innovation projects. These are listed in Table 3. Five alternative projects (A, B, C, D, E) are going to be evaluated with respect to these criteria by three DMs (DM1, DM2, DM3).
Evaluation criteria for innovation projects
Evaluation criteria for innovation projects
First, fuzzy criteria weights are obtained with hesitant F-AHP. In hesitant F-AHP, DMs make pairwise comparison of criteria with the linguistic terms in Table 1 and these comparisons are presented in Table 4.
Pairwise comparison of evaluation criteria by 3 DMs
After the combination of each DM’s evaluations with fuzzy envelope approach and aggregation of the corresponding TFNs of 3 DMs evaluations, the fuzzy evaluation matrix for the criteria weights (
The fuzzy evaluation matrix for the criteria weights (
Fuzzy criteria weights
3 DMs’ evaluation scores of the innovation projects with respect to each criterion
Fuzzy evaluation matrix (
Hesitant fuzzy AHP-VIKOR results for innovation project selection
In this paper, an integrated hesitant fuzzy AHP-VIKOR method is presented for the evaluation of innovation projects. In this method, hesitant F-AHP is used to determine the fuzzy criteria weights, and hesitant F-VIKOR is used to rank alternatives utilizing these fuzzy weights.
At present, there does not appear to be a study in the literature that integrates hesitant F-AHP and hesitant F-VIKOR and also an application of this integtation to the evaluation of innovation projects. Here, to model uncertainty and vagueness of judgments of decision makers, linguistic terms and fuzzy numbers are used, and in the presence of competing criteria, alternatives are ranked without too many repetitive pairwise comparisons and complex calculations. Moreover, usage of hesitant fuzzy linguistic terms in decision making provides DMs flexibility and also reflects the degree of hesitation DMs might have in reality. In this research, outer-dependence, inner-dependence, and feedback relations that might occur between criteria are not taken into consideration due to the limitations of hesitant F-AHP, however, for future research, these relations between criteria can be investigated with hesitant F-ANP and hesitant F-ANP can be integrated with hesitant F-VIKOR for evaluation and ranking problems.
