Novel Decision Making Methodology under Pythagorean Probabilistic Hesitant Fuzzy Einstein Aggregation Information
Institute of Mathematics, Khwaja Fareed University of Engineering & Information Technology, Rahim Yar Khan, 64200, Pakistan
2 Department of Mathematics, University of Sargodha, Sargodha, 40100, Pakistan
3 Department of Mathematics, Deanship of Applied Sciences, Umm Al-Qura University, Makkah, 24382, Saudi Arabia
* Corresponding Author: Muhammad Naeem. Email:
(This article belongs to this Special Issue: Decision making Modeling, Methods and Applications of Advanced Fuzzy Theory in Engineering and Science)
Computer Modeling in Engineering & Sciences 2023, 136(2), 1785-1811. https://doi.org/10.32604/cmes.2023.024851
Received 09 June 2022; Accepted 19 October 2022; Issue published 06 February 2023
AbstractThis research proposes multicriteria decision-making (MCDM)-based real-time Mesenchymal stem cells (MSC) transfusion framework. The testing phase of the methodology denotes the ability to stick to plastic surfaces, the upregulation and downregulation of certain surface protein markers, and lastly, the ability to differentiate into various cell types. First, two scenarios of an enhanced dataset based on a medical perspective were created in the development phase to produce varying levels of emergency. Second, for real-time monitoring of COVID-19 patients with different emergency levels (i.e., mild, moderate, severe, and critical), an automated triage algorithm based on a formal medical guideline is proposed, taking into account the improvement and deterioration procedures from one level to the next. For this strategy, Einstein aggregation information under the Pythagorean probabilistic hesitant fuzzy environment (PyPHFE) is developed. Einstein operations on PyPHFE such as Einstein sum, product, scalar multiplication, and their properties are investigated. Then, several Pythagorean probabilistic hesitant fuzzy Einstein aggregation operators, namely the Pythagorean probabilistic hesitant fuzzy weighted average (PyPHFWA) operator, Pythagorean probabilistic hesitant fuzzy Einstein weighted geometric (PyPHFEWG) operator, Pythagorean probabilistic hesitant fuzzy Einstein ordered weighted average (PyPHFEOWA) operator, Pythagorean probabilistic hesitant fuzzy Einstein ordered weighted geometric (PyPHFEOWG) operator, Pythagorean probabilistic hesitant fuzzy Einstein hybrid average (PyPHFEHA) operator and Pythagorean probabilistic hesitant fuzzy Einstein hybrid geometric (PyPHFEHG) operator are investigated. All the above-mentioned operators are helpful in design the algorithm to tackle uncertainty in decision making problems. In last, a numerical case study of decision making is presented to demonstrate the applicability and validity of the proposed technique. Besides, the comparison of the existing and the proposed technique is established to show the effectiveness and validity of the established technique.
Coronavirus disease 2019 (COVID-19) is a highly contagious sickness that can range from mild to severe. Fever, cough, and shortness of breath are common symptoms of COVID-19, which can escalate to acute respiratory distress syndrome, which causes breathing problems, a low ratio of the partial pressure arterial oxygen to the fraction of inspired oxygen (PaO2/FiO2), and multi-organ failure [1,2]. MSCs were first found in the bone marrow in 1991, but they can now be extracted from a variety of tissues, including the umbilical cord and adipose tissue . MSCs have anti-inflammatory characteristics due to their ability to modify cellular immune responses. MSCs can be used to treat a variety of disorders due to their regeneration capabilities and immunoregulatory function . Finding and testing acceptable MSC methods with effective utilization may be difficult since MSCs must first meet the selection and general requirements. Additionally, dealing with very precious MSCs and a huge number of patients needs an intelligent transfusion approach for COVID-19 patients with varying degrees of sickness severity, making prioritization problematic. This method falls under a multicriteria decision making (MCDM) problem since the needs in the second stage should follow the ranking of emergency COVID-19 patients in each severity level according to the evaluation criteria. As a result, choosing the finest MSC preparation process that conforms with national health laws, as well as selecting the most suited patients for the treatment, is critical for delivering effective cell-based therapy. To assist medical teams in solving the complicated obstacles outlined above, intelligent computing concerns should be addressed in order to present a fully intelligent real-time MSC transfusion framework based on the emergency severity of COVID-19 patients. Triage and prioritization are used in the medical field to either classify patients into distinct emergency categories or to prioritize them in the hereafter. Triage is an emergency medical procedure that classifies the severity of a patient’s condition and defines the treatment sequence. Automating this task could considerably enhance the quality of patient treatment and hospitalization, allowing for the greatest number of lives to be saved. Patients with chronic heart disease were previously classified into distinct emergency levels using an automated triage approach.
In fact, a system’s complexity grows more and more, making it impossible for DMs to select the best option among a wide range of viable options. It is difficult to put into words how challenging achieving a single objective is, yet it is not unattainable. Several corporations are faced with encouraging workers, identifying aims, and creating viewpoint. As a result, whether affecting individuals or panels, organizational decisions must consider a number of goals simultaneously. In this context, each DM should be restricted to finding the optimum solution for each factor associated with real problems, based on criteria that can be handled consciously. For decision-makers, establishing suitable ways for deciding on the appropriate option has become increasingly vital.
Classic or crisp procedures may not necessarily be the most successful when dealing with unstructured situations in decision-making circumstances. Zadeh  developed fuzzy sets (FS) in 1965 as a technique to manage such inconsistency. In FSs, Zadeh assigns membership grades to a set of components in the interval [0,1]. Zadeh’s work on this topic is notable since many of the set theoretic elements of crisp circumstances were described for fuzzy sets and it plays an important role in decision making [6,7].
Atanassov  investigated the intuitionistic fuzzy set (IFS), a better variation of the fuzzy set (FS) that includes both membership and non-membership degrees. IFSs have been shown to be useful and commonly used by researchers to evaluate uncertainty and instability in data throughout the previous few decades. Several researchers work on it, such as Yue  proposed the bilateral matching decision-making for knowledge innovation management taking into account matching willingness by using the intuitionistic fuzzy set environment, group decision making , aggregation operators , geometric aggregation operators , etc.
Wherever the MG and NMG numbers are more than one, the DMs are frequently confronted with certain qualities. In that circumstance, IFSs have little chance of producing a satisfactory result. To handle such a circumstance, Yager  proposed the Pythagorean fuzzy set (PyFS), which is a broad form of IFS. For PyFS, the sum of the squares of MG and NMG equals one. Wan et al.  introduced a three-step process for managing haze using the Pythagorean fuzzy multi-attribute group decision making, Yager et al. [15,16] also presented decision making procedures by using PyFS, Peng et al.  proposed some PyFS results. Torra  created the hesitant fuzzy set (HFS) to demonstrate the FS more firmly than the previous classical fuzzy set modifications, which needed the membership to have a set of specific values. Yue et al.  introduced the methodology for matching two-sided under hesitant fuzzy information and discussed their application related to smart intelligence, Xia et al.  presented hesitant fuzzy aggregation information, Liu et al.  introduced generalized power aggregation operator, Yu et al.  presented the MCDM under choquet integral based on HFS, Zhang  introduced the power aggregation operator, Liao et al. [24,25] introduced the hybrid and extended hybrid weighted aggregation operator on HFS, Joshi et al.  introduced TOPSIS method based on interval valued IHF choquet integral and similarly many other researchers also worked on HFS.
The concept of Pythagorean HFS (PyHFS) was suggested by Khan et al. . They developed operators to aggregate the data and proposed a comparison mechanism. Wan et al. [28,29] presented the decision methodologies under Pythagorean fuzzy information and Garg  presented hesitant PyF (HPyF) maclaurin symmetric mean operator, Garg et al. [31,32] introduced aggregation operators on HPyFS and Khan et al.  introduced hybrid aggregation operators on PyHFS. Zulqarnain et al.  developed some aggregation operators under interval-valued Pythagorean fuzzy soft information. Batool et al.  proposed the notion of a Pythagorean probabilistic hesitant fuzzy set and investigated its application in decision-making approaches. PyPHFS has both positive and negative hesitant membership degrees with the restriction that the square sum of the positive and negative hesitant membership degrees is either less than or equal to one. The DMs in PHFS is constrained to a single domain and are unaware of the negative membership degree or its possible occurrence probabilities. Each hesitantly negative membership level also has a preference over others. If one DM includes values 0.3, 0.4, and 0.6 for positive membership degree with their associated preference values 0.1 and 0.9, other DM may reject. As an example, the DMs may offer their opinions on DM difficulties in the form of multiple alternative values. Under the PyPHFS idea, the possibility of rejection level with hesitation is taken into account. Despite HFSs and PHFSs, the information about chances will reduce. The probability of occurrence with positive and negative membership degrees provides extra information on the degree of disagreement among the DMs. Batool et al.  also used its application for Fog-Haze Factor Assessment Problem.
Different priority levels are frequently assigned to each criterion in each emergency situation, adding to the task’s complexity. Ultimately, a COVID-19 patient prioritization process inside each emergency/triage situation necessitates a synchronized evaluation of the inverse relationship among the criteria, resulting in a trade-off. To address the first issue, an accurate automated triage guideline must be developed and implemented into the proposed MSC transfusion system. By prioritizing COVID-19 patients within each triage level, MCDM approaches are critical for overcoming the aforementioned problems. MCDM is a multi-objective decision model that is an extension of decision theory. It can address multi-criteria decision-making problems by constructing a decision matrix based on the intersection of each triage level’s evaluation criteria. The fundamental purpose of the MCDM is to rank/prioritize a group of alternatives based on a variety of evaluation criteria. For the MCDM technique Pythagorean Probabilistic Hesitant Fuzzy Information Aggregation when dealing with difficulties like this, Einstein Operations can be quite useful.
In this research work, we administered the Einstein aggregation operators (AOs) to PyPHFS environment, i.e., PyPHFEWA, PyPHFEOWA, PyPHFEHWA, PyPHFEWG, PyPHFEOWG and PyPHFEHWG operator. Idempotency, boundedness, and monotonicity are among the properties of the recommended operators that are established. The PyPHF AOs are taken into consideration by such operators in probabilistic scenarios, which is their main benefit. In the case of probabilistic material, the lack of PyPHFE AOs could lead to a scarcity of probabilistic information.
The paper is arranged in the prescribed manner. Section 2 contains the definition of FSs, IFSs, PyFSs, HFSs, and PyHFSs, PyPHFSs as well as PyPHFE aggregation operators. Section 3 is comprised of the PyPHFEWA, PyPHFEOWA, PyPHFEHWA, PyPHFEWG, PyPHFEOWG, and PyPHFEHWG operators, as well as their features such as monotonicity, idempotency, and boundedness. Section 4 presents how to use the MCDM technique. Section 5 contains the conclusion and discussion of the study.
In this section, let’s review the fundamentals of fuzzy sets, intuitionistic fuzzy sets, and Pythagorean fuzzy sets. These concepts will be used here when they have been reviewed.
Definition 2.1. For a fixed set . A FS in is presented as
for each the positive membership grade specifies the degree to which the element where be the unit interval.
Definition 2.2. For a fixed set . An IFS in is presented as
for each the positive membership grade and the negative membership grade specifies the positive and negative degrees of membership of to the Intuitionistic fuzzy set respectively, where be the unit interval. Moreover, it is required that for each .
Definition 2.3. For a fixed set . A PyFS in is presented as
for each the positive membership grade and the negative membership grade specifies the positive and negative degrees of membership of to the Pythagorean fuzzy set respectively, where be the unit interval. Furthermore, it is required that for each . Conventionally, is said to be degree of hesitancy of to
In what follows, we symbolize by the group of all Pythagorean fuzzy sets in . For ease, we shall symbolize the Pythagorean fuzzy number (PyFN) by the pair
Definition 2.4. Let Then
(1) if and only if and for each Clearly if and
Definition 2.5. For a fixed set . A HFS in is presented as
where is in the form of set, that is contained some possible values in unit interval, i.e., which represents the membership degree of in .
Definition 2.6. Let Then
Definition 2.7. For a fixed set . A PyHFS in is presented as
for each the positive membership grade and the negative membership grade are sets in some values in specifies the possible positive and negative degrees of membership of to the Pythagorean hesitant fuzzy set respectively. Furthermore, it is required that and The PyHF Number (PyHFN) will be denoted by the pair for convenience.
Definition 2.8. Let and be two PyHFNs. The basic operational laws defined as
Definition 2.9. For a fixed set . A PHFS in is presented as
where is subset of and represents the membership degree of in And represents the possibilities of , with the constraint that
Definition 2.10.For a fixed set . A PyPHFS in is presented as
for all and are sets of some values in Where & specifies the possible positive and negative degrees of membership of to the Pythagorean probabilistic hesitant fuzzy set respectively. and represent the possibilities of membership grades Also, there is and with (L is a positive integer to describe the number of elements contained in PyPHFS), where Furthermore, it is required that and For ease, we shall symbolize the Pythagorean Probabilistic Hesitant Fuzzy Number (PyPHFN) by the pair The group of all Pythagorean probabilistic hesitant fuzzy sets in is symbolized by
Definition 2.11.Let and be two PyPHFNs. The basic operational laws defined as
Definition 2.12.Let and be two PyPHFNs and , then their operations are presented as
Definition 2.13.For any PyPHFN a score function be defined as
where represents the number of elements in and represents the number of elements in
Definition 2.14.For any PyPHFN an accuracy function is defined as
where represents the number of elements in and represents the number of elements in
Definition 2.15.Let and be two PyPHFNs. Then by using above definition, comparison of PyPHFNs can be described as
(1) If then
(2) If and then
Definition 2.16.Let be any group of PyPHFNs, are the weights of with Then
(1) the PyPHFWA operator can be described as
(2) the PyPHFWG operator can be described as
Definition 2.17.Let be any group of PyPHFNs, be the jth largest in them and are the weights of with Then
(1) PyPHFOWA operator can be described as
(2) PyPHFOWG operator can be described as
Definition 2.18.Let be any group of PyPHFNs, is the jth largest of . Then the following two aggregation operators with aggregation-associated vector , where , can be described as
(1) PyPHFHWA operator
(2) PyPHFHWG operator can be described as
The application of t-norms in FS theory at the intersection of two FSs is widely recognized. T-conorms are being used to model disjunction or union. These are a straightforward explanation of the conjunction and disjunction in mathematical fuzzy logic syntax, and they are utilized in MCDM to combine criteria.
The Einstein sum () and Einstein product () are case studies of t-conorms and t-norms, respectively, and are stated in the PyPHF environment as follows:
Based on the above Einstein operations, we give the following new operations on PyPHFEs.
Definition 2.19.Let and be two PyPHFEs and , then
In this section, we develop several new Einstein operators for PyPHFNs, namely the Pythagorean probabilistic hesitant fuzzy Einstein weighted averaging (PyPHFEWA) operator, the Pythagorean probabilistic hesitant fuzzy Einstein ordered weighted averaging (PyPHFEOWA) operator, the Pythagorean probabilistic hesitant fuzzy Einstein weighted geometric (PyPHFEWG) operator, and the Pythagorean probabilistic hesitant fuzzy Einstein ordered weighted geometric (PyPHFEOWG) operator.
Definition 3.1.Let be a collection of PyPHFNs, are the weights of with Then such that
is called the Pythagorean probabilistic hesitant fuzzy Einstein weighted averaging operator.
Theorem 3.1.Let be a collection of PyPHFNs. Then the aggregation result using PyPHFEWA, we can achieve the following:
where are the weights of with with
Proof. We will demonstrate the theorem by mathematical induction. For
Since both and are PyPHFNs, and also, is a PyPHFN.
Thus, the result holds for
Assume that the results holds for
Now we will prove for
There are some properties which are fulfilled by the PyPHFEWA as follows:
Theorem 3.2.Let be a collection of PyPHFNs, are the weights of with with then we have the following:
(2) Monotonicity: Let be a collection of PyPHFNs. If while the probabilities are same. Then
Proof. (1) Let then so f(x) is a decreasing function. Let max and min
Since are the weights of with with we have
Definition 3.2.Let be a collection of PyPHFNs, are the weights of with Then such that
is called the Pythagorean probabilistic hesitant fuzzy Einstein weighted geometric operator.
Theorem 3.3.Let be a collection of PyPHFNs. Then the aggregation result using PyPHFEWG, we can achieve the following
where are the weights of with with
There are some properties which are fulfilled by the PyPHFEWG as follows:
Theorem 3.4. Let be a collection of PyPHFNs, are the weights of with with then we have the following:
(2) Monotonicity: Let be a collection of PyPHFNs. If while the probabilities are same. Then
We developed the following ordered weighted operators based on PyPHFNs.
Definition 3.3.(1) Let be a collection of PyPHFNs, are the weights of with Then such that
where be the th largest in them, is called the Pythagorean probabilistic hesitant fuzzy Einstein ordered weighted averaging operator.
(2) Let be a collection of PyPHFNs, are the weights of with Then such that
where be the th largest in them, is called the Pythagorean probabilistic hesitant fuzzy Einstein ordered weighted geometric operator.
Step 1 Normalization of the Expert information in Pythagorean probabilistic hesitant fuzzy information.
Step 2 We determine the weight vectors by using the Pythagorean probabilistic hesitant fuzzy entropy measure, entropy of the criteria is defined as
Step 3 By exploiting the proposed PyPHFWA operator/PyPHFWG operator, the overall preference values of the alternative are calculated as following formulas:
Step 4 Find out the score values for each given alternative using the following formula:
Step 5 Rank the alternative in ascending order. The alternative having large score value are the best alternative among the consider alternatives.
Flow chart of the proposed decision making methodology is given in Fig. 1.
Case Study: We present a real specific example of an emergency caused by a novel coronavirus outbreak (NCoViD-2019) that occurred in China to demonstrate the objectivity and operation of the suggested methodology. NCoViD-2019 is a brand-new virus that has infected thousands of people in just a few weeks. The virus has killed about 3,000 people in China, and it has afflicted more than 80,000 people around the world. Due to the nature of the emergency, the DMs must act quickly and rescue those who are in danger in order to effectively control the situation and prevent further deaths. There are three important factors to communicating emergency response requirements:
(1) Launch to save Persons influenced by the disease: Effective actions should be done to save the lives of those who have been impacted and are trapped. In addition, infected people should be transported to the hospital immediately and placed in separate units.
(2) Manage the problem as soon as possible: In the event of an emergency, the rescue workers should adopt steps to correct the situation and identify the presence of a virus, such as establishing isolation wards, vaccinating persons, and locking down the borders. Techniques for detecting and treating sick people could be used.
(3) Recovering from viruses and preventing others from contracting them: Individuals who are releasing the virus may be impacted by medical therapy, which could get others sick. Antibiotics are used to treat the infection. Persons suffering from respiratory ailments should seek medical attention, and a test must be performed. Use hand sanitizer on a regular basis. Make an effort to exercise and get proper sleep. Be aware of your surroundings’ symptoms, including coughing or fever.
To combat NCoViD-2019, there are four emergency options: = build high-tech wards in hospitals, = vaccinate persons, = lock down the borders, and = check and cure strategies. The expert information is given in Table 1.
= (0.314, 0.355, 0.331)
Step 1 Because the attributes are uniform so there are no need to normalized.
Step 2 The weight vector in this case study is known = (0.314, 0.355, 0.331). So we do not need to determine using proposed entropy measures.
Step 3 By exploiting the proposed PyPHFWA operator, we achieve the overall preference values of the alternative For instance
Similarly for other alternatives
Step 4 The score values are obtained as
The best choice is
Step 3 By exploiting the proposed PyPHFWG operator, we achieve the overall preference values of the alternative
Step 4 The score values are obtained as
The best choice is
To show the applicability and appropriateness of the established Pythagorean probabilistic hesitant fuzzy Einstein operators-based methodology, we compared the approach based on the suggested operator in accordance with the existing decision assistance approach to validate the advantages and stability of the developed methodology.
Comparison with Batool et al. :
Batool et al.  evolved novel Algebraic aggregation operators under Pythagorean probabilistic hesitant fuzzy information to sort out the best alternative. Table 3 gives the comparison findings and shows that the PyPHFWA, PyPHFOWA, PyPHFHWA, PyPHFWG, PyPHFOWG and PyPHFHWG operators are special instances of our developed Einstein aggregation operators.
In a nutshell, our suggested solutions are expected to become more extensive and flexible than a few existing strategies for addressing MADM problems. Collected specialist data  is listed in Table 2.
Given weight vector is
Table 3 shows a comparison between the existing technique and the results obtained by the proposed methodology along with the final ranking order of the alternatives. The operators in the considered existing theories are: PyPHFWA, PyPHFOWA, PyPHFHWA, PyPHFWG, PyPHFOWG and PyPHFHWG aggregation operators by Batool et al. . Thus, the proposed operators are an enhanced and generalized form of the existing operators because it remains unchanged on the same output ranking for different operators. Moreover, the best alternative chosen by the proposed operators remains the same as that with that of the existing operator signifies that the established operators are an enhanced version and generalized over the existing operator in the literature.
We conducted a thorough investigation into PyPHF aggregation operators in this paper. First, we have defined certain operational guidelines based on Einstein operations for PyPHFS. The weighted averaging and geometric Einstein aggregation operators have also been intended to deal with PyPHF data, such as Pythagorean probabilistic hesitant fuzzy averaging (PyPHFA) and Pythagorean probabilistic hesitant fuzzy geometric (PyPHFG) aggregation data in decision-making issues, due to the importance of operating procedures and a number of useful characteristics have been shown on them. To explain the usage, adaptability, and effectiveness of the procedure, we created a Healthcare framework and employed specified aggregation material to solve this problem.
We will examine the conceptual framework of Pythagorean probabilistic hesitant fuzzy sets for Einstein operations in future work using innovative decision-making approaches like as TOPSIS, VIKOR, EDAS and how these techniques are used in domains including analytical thinking, intelligent systems, soft computing, etc.
Acknowledgement: The authors would like to thank the Deanship of Scientific Research at Umm Al-Qura University for supporting this work by Grant Code: 22UQU4310396DSR32.
Funding Statement: The authors received no specific funding for this study.
Conflicts of Interest: The authors declare that they have no conflicts of interest to report regarding the present study.
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