Abstract
A divergence measure plays a crucial part in discriminating two probability distributions and drawing inferences constructed on such discrimination. The intention of this study is to propose such a divergence measure based on Jensen inequality and exponential entropy in the settings of probability theory. Further, the idea has been generalized to fuzzy sets to familiarize a novel picture fuzzy divergence measure. Besides proposing the validity, some of its key properties are also deliberated. Finally, two illustrative examples are solved based on the proposed picture fuzzy divergence measure which shows the expediency and effectiveness of the proposed approach.
1. Introduction
Decision making (DM) means that the optimal alternative is selected from the finite set of alternatives according to the multiple criteria, which can be regarded as cognitive processing. Decision making theory is a very important branch, which is used mostly in human activities. Because the real decision making problems are frequently produced from a complicated environment, the evaluation information is usually fuzzy. In general, the fuzzy information takes two forms: one quantitative and other one is qualitative. The quantitative fuzzy information can be expressed by fuzzy set (FS) [1], intuitionistic fuzzy set (IFS) [2], Pythagorean fuzzy set (PyFS) [3,4], picture fuzzy set (PFS) [5] and so on. FS theory proposed by Zadeh [1] has been used to describe fuzzy quantitative information which contains only a membership degree. Due to its successful applications and some shortcomings, many researchers introduced the extended forms of fuzzy set.
Atanassov [2] defined the notion of intuitionistic fuzzy set. In different areas, intuitionistic fuzzy set theory is applied, but in real life, some situations occur that cannot be handled by IFSs. Voting is a good example, because in voting human opinions involving more types of answers such as: “yes”, “abstain”, “no” and “refusal”. For example, in a democratic election station, the council issues 500 voting papers for a candidate. The results of the voting are divided into four groups accompanied with the number of papers that are “vote for” , “abstain” , “vote against” and “refusal of voting” . Here, group “abstain” means that the voting paper is a white paper rejecting both “agree” and “disagree” for the candidate but still takes the vote, group “refusal of voting” is either invalid voting papers or did not take the vote. The candidate is successful because the number of support papers is over half (i.e., 250). However, at least 5 people said later on in their blogs that they supported the candidate in the last moment because they found that the support number seemed larger than the against number. Such kinds of examples (in which the number of abstains is a key factor and the group “refusal of voting” indeed exists) happened in reality and intuitionistic fuzzy set could not handle it. So, Cuong [5,6] defined the extension of fuzzy sets and intuitionistic fuzzy sets, which is picture fuzzy sets. The concept of picture fuzzy set for an element is that, there are three membership degrees namely, positive membership degree, the neutral membership degree, and the negative membership degree, respectively. The picture fuzzy set theory is used in many real life problems such as voting problems, clustering [7], fuzzy inference [8], and decision making [9,10,11,12,13,14,15].
In view of these developments, we will present new similarity measures for the PFSs. A similarity measure give the similarity degree of objects i.e., how similar these objects are. The similarity measures developed in [8,16,17,18] have some limitations and cannot be applied to those problems in which the information occurred in the picture fuzzy environment. To resolve this issue, some novel proposed measures which are generalizations of the similarity measures were developed in [8,16,17,18]. It is also proved that existing similarity measures become special cases of the developed similarity measures, showing the novelty and diversity of the proposed similarity measures. Applying the new similarity measures, we solved decision making problems and their results are discussed.
The remainder of the study is designed as follows. Section 2 briefly discusses the basic knowledge of extension of fuzzy sets. The novel idea “Picture Fuzzy Divergence Measure” is presented in Section 3. Section 4 makes some discussions on basic properties and Section 5 presents the application of the proposed method. Section 6 discusses the advantages of the proposed work. Conclusions are drawn in Section 7.
2. Preliminaries
The article gives a brief discussion on the basic ideas associated with PFS along with their operations and operators. We also discuss more familiarized ideas, which are utilized in the following analysis.
Cuong [5] proposed the idea of picture fuzzy sets and their basic operational rules are as follows
Definition 1.
For a set R, by a picture fuzzy set in R we mean a structure
in which , and are indicated the positive, neutral and negative grads in R. In addition, following condition satisfied by and is ; for all Then μ is said to be picture fuzzy set in
Definition 2.
Let and be two PFSs in R. Then
- (1)
- if and only if and for all
- (2)
- if and only if and
- (3)
- (4)
- (5)
Definition 3.
A function such that for all is said to be a triangular-norm, if it satisfies the following properties:
- (1)
- (2)
- (3)
- whenever
- (4)
Definition 4.
A function such that for all is said to be a triangular-conorm, if it satisfies the following properties:
- (1)
- (2)
- (3)
- whenever
- (4)
Joshi and Kumar [17] discussed the basic norms functions which are defined as
Definition 5.
Some basic norms are the following:
- (1)
- Minimum traingular-norm:
- (2)
- Product traingular-norm:
- (3)
- Lukasiewicz traingular-norm:
- (4)
- Drastic product traingular-norm:
Similarly, we define the four basic triangular-conorms.
3. Picture Fuzzy Divergence Measure
History: Suppose that are the complete probability distributions set. Shannon entropy of a set G is follows as:
The concavity of gives us a decomposition of the overall diversity in a mixed distribution is follows;
The first part of Equation (2), that is denotes the average diversity within distributions, where the second component, that is
is called the Jensen difference arising out of the convex function which is nonnegative and disappears if and only if and this gives a natural measure of divergence between the distributions G and It is notable that assumed as a function of is convex, which meets the intuitive condition that the average divergence between , and is not less than that between their convex combination where and The convexity of divergence measure is an additional attractive feature of the Shannon entropy as a measure of diversity of a distribution. The application of measure of diversity is discussed in [19,20].
In this study, we assume that the Jensen difference Equation (3) arising from a generalized class of entropy functions including the exponential entropy due to Pal and Pal [21], which is called an exponential J-divergence, and examine its convexity. The convexity of J-divergence Equation (3) is proved, based on the exponential entropy given by
The author claims that Equation (4) has some advantages over Equation (1) specifically in image processing. Another claim is that entropy Equation (4) has a fixed upper bound, that is, for a uniform distribution lim as compared to infinite limit (as in the case of Equation (1).
For any two probability distributions with respect to the weights Lin [22] defined Jensen-Shannon divergence as:
Since Equation (1) denotes a concave function, according to the Jensen inequality, when then is nonnegative and is equal to zero. Based on the concept of Jensen-Shannon divergence (Lin [22]), corresponding to Equation (4), for any two probability distributions with and as their respective weights satisfying we define a new divergence measure as:
Definition 6.
The Hessian function j of any two variables g and d is
A function j is convex at any point in its domain if Hessian is positive semi-definite and concave if Hessian is negative semi-definite at that point.
To justify the existence of new divergence measure, which is:
we have to prove that proposed divergence measure satisfies the following properties.
Some major properties of proposed divergence measure are the following:
- (1)
- with equality when
- (2)
- is a convex function of G and
Proof.
We have to show that For this from Jensen’s inequality, we have
This implies
Now, we have to show the convexity of function where
Taking partial differential of the above example with respect to g and we obtain
and
Put and to find the stationary point.This gives as a stationary point. Now, computing the Hessian of j at and using we obtain
which is positive semi-definite. This confirms the convex character of □
Now, we propose the novel divergence measure based on the Jensen’s divergence as follows:
Definition 7.
Let the universe set R, , be two PFNs in R and Picture fuzzy divergence measure is define as,
4. Properties of Picture Fuzzy Divergence Measure
Picture fuzzy divergence measure for PFNs satisfies the following defined properties as;
Theorem 1.
Let the universe set R, , and be any three PFNs in Then
- (1)
- (2)
- iff
- (3)
- iff for all
- (4)
- (5)
- (6)
- (7)
- (8)
- (9)
- (10)
- (11)
- (12)
- (13)
- (14)
where and represent the compliment of the PFSs and respectively.
Proof.
Suppose that R bifurcate into two parts f and such that
- Properties (1)–(3) are proved directly from the Definition 5
- Property (4) as follows. SinceThis impliesSimilarly, we can prove that
- From the property (5),We haveSimilarly, we can prove that
- Proof of this property (6) is follows as the proof of properties (5) & (1).
- Proof of this property (7)
- Proof of this property (8) follows as the proof of property (7).
- Proof of this property (9), considerThis impliesTherefore,
- Proof of this property (10) is follows as the proof of property (9).
- Proof of this property (11), considerUsing (10), we obtain
- Proof of properties (12), (13) and (14) follows directly from Definition 5.
□
5. Applications of Proposed Picture Fuzzy Divergence Measure in MADM
In this section, the picture fuzzy divergence measure between picture fuzzy sets is applied to the medical diagnosis and Pattern Recognition.
5.1. Divergence Measure for Medical Diagnosis
Assume that a set of diagnoses G , , , and the set of symptoms are . Suppose that the patients, with respect to all symptoms, can be depicted by the following PFS synthetic information:
Then each diagnoses can be viewed as PFSs with respect to all the symptoms as follows:
Discussion on Obtaining Results
Our purpose is to classify the patients in one of the diagnoses classes For this, the proposed picture fuzzy divergence measure has been measured from each P to and are given above. Results are shown in Table 1, picture fuzzy divergence measures assign the unknown patients class to the known diagnoses class as follows, Patients and falls in diagnoses and respectively, according to the principle of the minimum degree of divergence measure between PFSs.
Table 1.
Diagnosis Results for Picture Fuzzy Divergence Measure.
Hence, conclude that the unknown class is related to the known class based on picture fuzzy divergence measure.
5.2. Divergence Measure for Pattern Recognition
Assume that a set of known patterns which are given in the PFSs form: Suppose the patterns synthetic data information in universe set as
Consider an unknown pattern is represented as
Discussion on Obtaining Results
In this study we classify the unknown pattern A in one of the known patterns For this, the proposed picture fuzzy divergence measure has from each A to and is given in Table 2. From the numerical results presented in the above table, picture fuzzy divergence measures assign the unknown patients class A to the known class , according to the principle of the minimum degree of divergence measure between PFSs.
Table 2.
Pattern Recognition Results for Picture Fuzzy Divergence Measure.
Hence, conclude that the unknown class A is related to the known class based on picture fuzzy divergence measure.
6. Advantages of the Proposed Picture Fuzzy Divergence Measure
(1) Although to solve MADM problem in different areas, IFS theory has been profitably tested, some situations in real life IFSs are not applicable. In those situations we used the PFSs, which are an extension of IFSs, so the PFS is most often better than the IFS. In some situations, the IFS cannot solve a problem which PFS can solve, e.g., if a DM gives information about positive, neutral and negative membership grades, then this type of problem is only valid for the PFS. Particularly, PFS is more capable of handling uncertain problems.
(2) In this paper, we use the picture fuzzy information and proposed a technique to making decisions in complex real life problems. Numerical examples proposed in this paper cannot be handled with pre-existing structures such as the fuzzy sets, intuitionistic fuzzy sets and cubic sets. So, our proposed technique is a generalization of the pre-existing structure of fuzzy sets to deal with real life decision making problems more smoothly.
(3) From the existing studies [8,16,17,18] it is observed that many researchers introduce different algorithms by utilizing divergence measures for IFSs. As mentioned above, in some situations, we cannot use the IFSs algorithm, because their corresponding algorithm may not give us applicable results.
(4) The divergence measures of IFS is a special case of the divergence measures of PFSs. Therefore, the defined picture fuzzy divergence measures are more generalized and acceptable to solve the MADM problem than the current ones.
7. Conclusions
In this article, we study and introduce an exponential Jensen picture fuzzy divergence measure successfully. The basic properties of picture fuzzy divergence measure are also introduced and discussed. Subsequently, we give a new method of decision-making problem based on the proposed divergence measure by analyzing the limitations and advantages in the existing literature. The decision steps of the decision method are also constructed. The proposed approach will yield an objective decision result based on information from the decision problem only. Some illustrative examples are used to show the appropriateness of the defined picture fuzzy divergence measure.
Author Contributions
Conceptualization, S.A. (Shahzaib Ashraf) and S.A. (Saleem Abdullah); methodology, S.A. (Shahzaib Ashraf); validation, S.Z.; formal analysis, S.Z.; writing—original draft preparation, S.A. (Shahzaib Ashraf); writing—review and editing, S.A. (Shahzaib Ashraf); supervision, S.A. (Saleem Abdullah).
Funding
This paper is supported by National Natural Science Foundation of China (No. 71671165), Zhejiang Province Natural Science Foundation (No. LY18G010007), Major Humanities and Social Sciences Research Projects in Zhejiang Universities (No. 2018QN058), Cooperation Project between Ningbo City and Chinese Academy of Social Sciences (No. NZKT201711) and K. C. Wong Magna Fund in Ningbo University.
Conflicts of Interest
The authors declare no conflict of interest.
References
- Zadeh, L.A. Fuzzy sets. Inf. Control 1965, 8, 338–353. [Google Scholar] [CrossRef]
- Atanassov, K.T. Intuitionistic fuzzy sets. Fuzzy Sets Syst. 1986, 20, 87–96. [Google Scholar] [CrossRef]
- Yager, R.R. Pythagorean fuzzy subsets. In Proceedings of the Joint IFSA World Congress and NAFIPS Annual Meeting, Edmonton, AB, Canada, 24–28 June 2013; pp. 57–61. [Google Scholar]
- Yager, R.R. Pythagorean membership grades in multicriteria decision making. IEEE Trans. Fuzzy Syst. 2014, 22, 958–965. [Google Scholar] [CrossRef]
- Cuong, B.C. Picture Fuzzy Sets-First Results, Part 1. In Seminar “Neuro Fuzzy Systems With Applications”; Preprint 03/2013; Institute of Mathematics: Hanoi, Vietnam, 2013. [Google Scholar]
- Cuong, B.C. Picture fuzzy sets. J. Comput. Sci. Cybern. 2014, 30, 409–420. [Google Scholar]
- Son, L.H.; Thong, P.H. Some novel hybrid forecast methods based on picture fuzzy clustering for weather now casting from satellite image sequences. Appl. Intell. 2017, 46, 1–15. [Google Scholar] [CrossRef]
- Son, L.H. Generalized picture distance measure and applications to picture fuzzy clustering. Appl. Soft Comput. 2016, 46, 284–295. [Google Scholar] [CrossRef]
- Ashraf, S.; Mahmood, T.; Abdullah, S.; Khan, Q. Different approaches to multi-criteria group decision making problems for picture fuzzy environment. Bull. Braz. Math. Soc. New Ser. 2018. [Google Scholar] [CrossRef]
- Garg, H. Some picture fuzzy aggregation operators and their applications to multi criteria decision-making. Arab. J. Sci. Eng. 2017, 42, 52–75. [Google Scholar] [CrossRef]
- Phong, P.H.; Cuong, B.C. Multi-criteria group decision making with picture linguistic numbers. VNU J. Sci. Comput. Sci. Comput. Eng. 2017, 32, 39–53. [Google Scholar]
- Wang, C.; Zhou, X.; Tu, H.; Tao, S. Some geometric aggregation operators based on picture fuzzy sets and their application in multiple attribute decision making. Ital. J. Pure Appl. Math. 2017, 37, 477–492. [Google Scholar]
- Wei, G. Picture fuzzy hamacher aggregation operators and their application to multiple attribute decision making. Fund. Inform. 2018, 37, 271–320. [Google Scholar] [CrossRef]
- Son, L.H.; Viet, P.V. Picture inference system: A new fuzzy inference system on picture fuzzy set. Appl. Intell. 2017, 46, 652–669. [Google Scholar] [CrossRef]
- Wei, G.; Alsaadi, F.E.; Hayat, T.; Alsaedi, A. Projection models for multiple attribute decision making with picture fuzzy information. Int. J. Mach. Learn Cybern. 2018, 9, 713–719. [Google Scholar] [CrossRef]
- Joshi, R.; Kumar, S.; Gupta, D.; Kaur, H. A Jensen α norm dissimilarity measure for intuitionistic fuzzy sets and its applications in multiple attribute decision making. Int. J. Fuzzy Syst. 2017, 20, 1188–1220. [Google Scholar] [CrossRef]
- Joshi, R.; Kumar, S. Exponential Jensen intuitionistic fuzzy divergence measure with applications in medical investigation and pattern recognition. Soft Comput. 2018. [Google Scholar] [CrossRef]
- Srivastva, A.; Mahashwari, M. Decision making in medical investigations using new divergence measures for intuitionistic fuzzy sets. Iran J. Fuzzy Syst. 2016, 13, 25–44. [Google Scholar]
- Garg, H.; Kaur, J. A Novel (R, S)-Norm Entropy Measure of Intuitionistic Fuzzy Sets and Its Applications in Multi-Attribute Decision-Making. Mathematics 2018, 6, 92. [Google Scholar] [CrossRef]
- Ponta, L.; Carbone, A. Information measure for financial time series: Quantifying short-term market heterogeneity. Phys. A Stat. Mech. Appl. 2018, 510, 132–144. [Google Scholar] [CrossRef]
- Pal, N.R.; Pal, S.K. Object background segmentation using new definition of entropy. IEE Proc. E 1989, 366, 284–295. [Google Scholar] [CrossRef]
- Lin, J. Divergence measure based on Shannon entropy. IEEE Trans. Inf. Theory 1991, 37, 145–151. [Google Scholar] [CrossRef]
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