Abstract
Stock evaluation is a significant decision-making activity for investors. Due to the complexity of stock exchange market, evaluation information may be fuzzy and stochastic in the meantime. Therefore, it is essential to conduct the research on fuzzy stochastic multi-criteria decision-making (FSMCDM) methods. In this paper, at the beginning, we propose interval neutrosophic probability from the definition of neutrosophic probability. Then, a novel MCDM method is proposed with interval neutrosophic probability based on regret theory, in which criteria values are interval neutrosophic numbers (INNs). The method proposed with interval neutrosophic probability may be much better than methods using classic probability or fuzzy probability. Next, we apply the proposed method to stock selection problems and discuss the influence of parameters on ranking results. Finally, we compare regret theory with prospect theory, which is also an important theory of bounded rationality just like regret theory, to emphasize the characteristics the regret theory. Moreover, a comparative analysis is also conducted between the proposed method and existing methods under interval neutrosophic environment to demonstrate efficiency and applicability of the proposed method.
Keywords
Introduction
The capital market especially stock market has developed rapidly in recent years. more and more investors invest a large amount of money into the stock market [1]. However, the stock market is often complex and variable. Therefore, stock evaluation is an important problem for investors [2]. Many multi-criteria decision-making (MCDM) methods [3–5] were utilized to deal with stock assessment problems [1, 6]. Due to complexity and variability of stock market, stock evaluation problem may have both fuzziness and randomness. To solve this type of problems, many researches on fuzzy stochastic multi-criteria decision-making (FSMCDM) methods has been studied [7–14], but there are some certain limitations in these methods. The limitations are outlined below.
Peng and Dai [7], Peng and Yang [8], and Peng et al. [9] proposed FSMCDM methods where criteria values are pythagorean fuzzy numbers, interval-valued fuzzy numbers, and trapezoidal fuzzy numbers, respectively. However, these fuzzy numbers only can express the fuzzy, uncertain, and incomplete information in the decision-making processes [15–18] while they overolook the neutrality in evalation information. Therefore, intuitionistic fuzzy numbers were used by Chen et al. [10] and Yuan and Li [11] to depict neutral information. Nevertheless, In some practical cases, there is much indeterminate and inconsistent information which intuitionistic fuzzy numbers cannot depict [19, 20]. Hence, the existing methods with fuzzy numbers or intuitionistic fuzzy numbers may not handle problems effectively and efficiently. Peng and Dai [7] and Peng and Yang [8] utilized point probability to represent the probability distribution of criteria values. Moreover, Liu et al. [12] and Peng et al. [9] proposed FSMCDM methods with interval probability and trapezoidal fuzzy probability, separately. Nevertheless, the point probability, interval fuzzy probability, and trapezoidal fuzzy probability only consider the fuzziness of events’ results while the indeterminacy of events’ results is not taken into accounts [21]. Yuan and Li [11] transformed an intuitionistic trapezoidal fuzzy random matrix into a score function matrix. And a hybrid method, integrating Mahalanobis-Taguchi Gram-Schmidt with improved evidence theory, was utilized to cope with the score function matrix. Espino et al. [13] proposed a multi-criteria model which combined Integrated Value Model for Sustainable Assessments (MIVES) method with some auxiliary complements, including Monte Carlo Simulations, fuzzy sets, and the AHP model. Similarly, Monte Carlo Simulation was combined with VIKOR technique in Ref. [14] to address FSMCDM problems. Obviously, the above methods are based on complete rationality. DMs’ psychological behaviors are not taken into considerations. The results derived from the above methods on the basis of complete rationality may be unreasonable [22].
In order to cover the deficiencies in the existing FSMCDM methods, we propose a FSMCDM method with interval neutrosophic probability based on regret theory within interval neutrosophic environment. Next, the literature reviews related to interval neutrosophic sets (INSs), interval neutrosophic probability, and regret theory, are introduced.
INSs can be regarded as the particular cases of neutrosophic sets (NSs) [20, 23]. To deal with the indeterminate and inconsistent information in practical problems, Smarandache [19, 20] proposed NSs in 1998. However, without a specific presentation, NSs cannot be applied in many real-life cases. Therefore, single-valued neutrosophic sets (SVNSs) were put forward as variations of NSs [20, 23]. In SVNSs, the truth-membership function, indeterminacy-membership function, and falsity-membership function are a single value in interval [0, 1]. Nevertheless, there is an issue when we use SVNSs, that is, experts are difficult to describe alternatives with a certain value in some practical circumstances. To solve this issue, Wang et al. [24] developed INSs where the degrees of truth, indeterminacy, and falsity are an interval value, respectively. If there is only one element in an INS, this element is called as an interval neutrosophic number (INN). The NSs and their particular cases have been applied in many practical problems [25, 26], including evaluation problem of e-commerce websites [27], third party logistics selection problem [28], and multi-criteria decision-making problem [29].
INSs can describe the uncertain information found in stock selection problems appropriately. For instance, an expert is invited to evaluate the prospects of stocks. The stocks will go up or down, and at the same time, there will be great uncertainty. Therefore, the expert may evaluate stocks from three perspectives that are the degree of good future development, the degree of bad prospects, and the uncertainty of stocks. After thinking of the fundamental and technological sides of a stock comprehensively, the expert may consider the degree of future development is between 0.6 and 0.9. Simultaneously, he or she may think the degree of bad prospects is ranging from 0.3 to 0.4. Further, the expert may consider the degree of indeterminacy is fall in the interval [0.2, 0.3]. In this case, the truth-membership degree, indeterminacy-membership degree, and falsity-membership degree of INSs can perfectly describe the degree of good future development, the degree of indeterminacy, and the degree of bad prospects, respectively. The evaluation information can be represented by INSs as
Many researchers have investigated MCDM methods under interval neutrosophic environment. The researches can be roughly grouped into three categories. The first group is based on aggregation operators, such as interval neutrosophic weighted averaging operator and weighted geometric operator [30], interval neutrosophic ordered weighted averaging operator and ordered weighted geometric operator [31], interval neutrosophic prioritized ordered weighted averaging operator [32] and some power generalized aggregation operators [33]. The second group is based on measures, including distance measure [34], similarity measures [35, 36], correlation coefficients [37, 38], and cross-entropies [39, 40]. The third group is on the basis of outranking relations [41].
Neutrosophic probability (NP) was originally proposed by Smarandache [21]. Then NP has been applied in many domains, such as quantum physics [42], data classification [43], target identification [44], but there is little research on NP in handling MCDM problems. NP is composed with three parts. That is, the chance that an event occurs, the chance that an event does not occur, and the indeterminate chance related to an event. Compared to point probability, interval probability, and fuzzy probability, it can depict the results of events perfectly. For example, there are two candidates No.1 and No.2 for presidency, and the probability that No.1 wins is 0.46, the probability that No.2 wins is 0.45, then 0.09 would be the probability of blank (the voters are not choosing any candidate) and black (the voters reject both candidates) votes together. Subsequently, point probability and fuzzy probability cannot describe three results at the same time. Neutrosophic probability that the candidate No.1 wins can be denoted by NP = (0.46, 0.09, 0.45) [21]. In some circumstances, experts give the probability with a range rather than a specific number. Therefore, interval neutrosophic probability, which is derived from NP, is developed in this study.
In order to make decisions more reasonable and effective, many studies have conducted based on bounded rationality rather than complete rationality. In the MCDM methods based on the assumptions of complete rationality, DMs make decisions with complete information, sufficient knowledge, and a large amount of time. However, in some practical decision-making cases, DMs are hard to select the alternative rationally due to their limitations of professional knowledge, information processing capability, and available time [22]. Thus, Simon [45] introduced the concept of bounded rationality in 1947. Since then, more and more MCDM methods have been studied in the perspective of bounded rationality [46, 47]. One of the most important decision-making theories is regret theory [22, 48].
In regret theory, DMs conduct comparison analyses between the results of selected alternative and results of other alternatives, so that their psychological behaviors will have regretful and joyful emotions. If the outcomes of selected alternative are worse than other alternatives, DMs may feel regretful during the decision-making processes. Otherwise, that is, if selected alternative is the best one, DMs may have rejoicing in their mind. Bell [49] and Loomes and Sugden [50] initially proposed regret theory, then many researchers have paid attention to regret theory [7, 8, 51]. Rai et al. [51] studied a compromise MCDM method in view of regret theory, subsequently, the method was utilized to deal with material selection problems. Moreover, Interval-valued fuzzy soft methods and pythagorean Fuzzy methods were proposed based on regret theory by Peng and Yang [8] and Peng and Dai [7], respectively.
Based on the above illustrations, a number of contributions are offered in this paper:
Interval neutrosophic probability is proposed to represent the fuzziness and indeterminacy of the result of one event, which is superior to classical probability and fuzzy probability in description. The method based on regret theory is firstly proposed under interval neutrosophic environment, and this method is significant in theoretical innovation. The proposed method is applied in Shanghai Stock Exchange and help investors to select stocks, which broaden the application environment of regret theory. Thus, this paper not only has theoretical innovation, but also has application contribution.
The rest of this paper is arranged below. In Section 2, we introduce the basic concepts of INSs and NP at the beginning. And the regret theory is also reviewed. In Section 3, we defined interval neutrosophic probability derived from NP. In Section 4, an MCDM method based on regret theory is proposed. Then, Section 5 provides an example of stock selection and compares the proposed method with the existing methods under interval neutrosophic environment. Similarly, a comparative analysis between prospect theory and regret theory is investigated. Section 6 offers a conclusion.
Preliminaries
This section presents the details of interval neutrosophic numbers and neutrosophic probability. Regret theory is also introduced. These definitions will be used in subsequent discussions.
Interval neutrosophic numbers
A is called an interval neutrosophic number (INN) if X has only one element, denoted by
Further, the operation laws and comparison method employed in subsequent discussion are referenced from Ref. [30].
Some notions related to NP are introduced in this subsection, and an example is given to illustrate the property of NP.
It should be noted that the sum of neutrosophic probability components may be greater than 1 when we forecast an event from different criteria. And the following example is illustrated.
Bell [49] and Loomes and Sugden [50] initially proposed regret theory which is an important reasoning method. The regret theory reflects preferences by a utility function which considers regret and rejoicing. Regret represents the difference in DMs’ position resulting from choosing one of the unselected alternatives instead of the selected alternative. Rejoicing represents the extra pleasure gained from knowing that the optimal alternative wasselected [22].
Let x
i
be the a criteria value of alternative A
i
for i = 1, 2, …, m, respectively. The modified utility function of obtaining x
i
is defined as [22]:
(1) The utility value
Let X = [X−, X+] be a criteria value, then the utility value of X is denoted by the following equation [52]:
Bell [49] defined utility function as:
In this paper, for probability density function, we take the normal distribution into consideration. The probability density function is defined as[53]:
(2) The regret-rejoice function
The regret-rejoice function is established to obtain the regret values of all alternatives. Bell [49] developed the regret-rejoice function by the following equation:
As the derivation of NP, interval neutrosophic probability is defined in this section. Next, an example is provided to illustrate the usage of interval neutrosophic probability.
In some real-life situations, NP cannot be used effectively to cope with MCDM problems. Due to the limitations of knowledge and complexity of environments, experts are hard to give specific numbers to describe the probabilities of events’ results. They may provide interval values because they cannot give the probability exactly. Therefore, interval neutrosophic probability is developed from NP. Since ch (φ), ch (indeterm
φ
), and
From Definition 5, we can easily obtain
The novel MCDM method with interval neutrosophic probability
In this section, we describe decision-making problems with interval neutrosophic probability, and then a novel MCDM method based on regret theory is proposed to solve them.
Description of the decision-making problems
For a MCDM problem with interval neutrosophic information, assume that there are m alternatives A
i
(i = 1, 2, …, m) to be evaluated with respect to n criteria C
j
(j = 1, 2, …, n). Suppose that the weight vector of decision criteria is ω = (ω1, ω2, …, ω
n
) where 0 ≤ ω
j
≤ 1 and
Decision-making procedures based on regret theory
The main procedures of novel MCDM method based on regret theory are studied in this subsection. The proposed method based on regret theory focus on regret aversion of DMs.
Since there are both benefit and cost criteria in an MCDM problem, the decision matrix should be standardized so as to transform various criteria value into comparable value. If criterion C
j
is a benefit criterion, interval neutrosophic number
Let
The utility values of
The regret values
Let E
ij
be the comprehensive perceived utility value for alternative A
i
in terms of criterion C
j
, then E
ij
can be calculated as follows:
The comprehensive perceived utility matrix is denoted by EX = (E ij ) m×n and E ij is an interval neutrosophic number.
The criterion weight ω
j
with respect to criterion C
j
can be calculated as follows:
Let
We can obtain the relative closeness degree D (A
i
) for the alternative A
i
by the equation below:
We can use relative closeness degree to rank all the alternatives. The greater the value of D (A i ) is, the better the alternative is.
In this section, the proposed method based on regret theory in this paper is applied in stock assessment process to demonstrate its effectiveness and applicability.
Shanghai Stock Exchange (SSE) is one of two stock exchanges in mainland China. Since the establishment of SSE in 1990, a great deal of companies was listed on the SSE. As of March 2017, there are 1236 companies come into SSE, of which the total market capitalization has reached ¥ 298 trillion. The SSE incorporates many industries included banking business, real-estate industry, manufacturing industry, construction business, and new energy industry. New energy is the resource beyond traditional energy which composes solar energy, wind energy, biomass energy, and geothermal energy. With the decreases of traditional energy on earth, the new energy leads to more and moreattentions.
An investment company wants to select a new energy stock in SSE to invest. Assume that there are four alternatives stocks to select. That is, Aerospace Electrical A1, Great Wall Electrical A2, Jingneng Thermal Power A3, and Minjiang Hydropower A4. To make decisions objectively and scientifically, this investment company invites many new energy experts to evaluate the stocks with respect to three criteria. That is, liquidity C1, profitability C2, and stability C3. The detailed descriptions of these criteria are shown in Table 1 and the criteria weights information is completely unknown.
Decision criteria and their descriptions
Decision criteria and their descriptions
During the process of stock selection, we should evaluate future trend of the stocks in corresponding stock markets. Since uncertainty is existing in stock exchange market, it has three possible status: good θ1, fair θ2, and poor θ3. The probability of each kind of status is an interval neutrosophic probability, denoted by INP1 = ([0.2, 0.5] , [0.1, 0.3] , [0.5, 0.6]), INP2 = ([0.3, 0.8] , [0.2, 0.3] , [0.4, 0.7]), and INP3 = ([0.4, 0.7] , [0.1, 0.2] , [0.4, 0.5]). Interval neutrosophic probability can fully depict the indeterminacy of three status, and the proposed methods with interval neutrosophic probability may be reasonable and feasible.
Many stocks under different status have different performance. Some stocks may have good performance under good status but have very bad performance under bad status. Also, some stocks may not have pretty good performance under good status but have not bad performance under bad status. Therefore, we should assess these stocks under three status, respectively. Fuzzy set theory is applied widely in the process of stock assessment [1, 6] to depict the evaluation information. And the unique properties of INNs introduced in Section 1 allow them to express fuzzy information perfectly and conveniently. As a result, we suggest experts utilize INNs to evaluate these four alternatives with respect to three criteria under three statuses. For example, when experts evaluate alternative A1 regarding criterion C1 under status θ1, they may consider the degree that A1 has good future development to fall within the range [0.7, 0.8]. Simultaneously, the experts think the degree that A1 has bad prospects is ranging from 0.2 to 0.4. Further, the degree of indeterminacy is 0.2 at least and 0.3 at most. In this case, the evaluation information is depicted as 〈 [0.7, 0.8] , [0.2, 0.3] , [0.2, 0.4]〉. All the assessment information of experts is presented as B1, B2 and B3.
DMs may have strong psychological activities in the process of stock selection. That is, DMs may have a feeling of regret aversion when choosing stocks. Therefore, the proposed method based on regret theory can be utilized to evaluate stocks effectively and efficiently.
In this subsection, we utilize the proposed method based on regret theory to evaluate the stock alternatives. All the alternatives are ranked and the best alternative is selected.
The decision matrix do not need to standardize since all the corresponding criteria for alternatives are benefit criteria.
According to comparison of criteria values, the ideal point can be identified by Equation (11). The ideal point is:
The utility values are calculated by Equation (12) and shown in Table 2.
The utility values
The regret values
The effect of parameter η on the ranking results
Giving parameter η = 0.3. Using Equation (13), the regret values can be computed in Table 3.
According to the utility values and regret values calculated before, the comprehensive perceived utility values can be obtained by Equation (14) and shown as follows:
Using Equation (15), the criteria weights are obtained as ω = (0.4008, 0.3727, 0.2264).
The positive and negative ideal solutions are determined by Equations (16, 17), and the ideal solutions are represented in the following paragraphs:
Using Equation (18), the relative closeness degrees are calculated as follows:
D (A1) = 0.3709, D (A2) = 0.3020,
D (A3) = 1.0000, D (A4) = 0.5150.
We can use relative closeness degrees to rank all the alternatives, That is, A3 ≻ A4 ≻ A1 ≻ A2. Further, the best alternative is A3.
This subsection investigates how the parameters influence the results of proposed method at the beginning. Then it conduct a comparative analysis between the method based on prospect theory and method based on regret theory regarding the features of each method. Finally, we compare the proposed method in this paper with the methods proposed under interval neutrosophic environment in other papers and the advantages of proposed method areconcluded.
(1) The effect of parameters on ranking results
For the parameters λ and η of regret theory, parameter λ was provided by scholars [7, 8]. However, the parameter η is variable. Therefore, we only need to change the parameter η to observe variation of ranking results, which is in Table 4.
When we change the parameter η, the ranking orders of all alternatives are not changed. The alternative A3 is the best and A2 is the worst all the time. Therefore, the proposed method based on regret theory has good stability in decision-makingprocess.
(2) Comparative analysis between prospect theory and regret theory
The prospect theory is also a significant theory based in bounded rationality just like regret theory. Thus, a comparative analysis is studied between the method based on prospect theory and method based on regret theory.
According to Refs. [54, 55], the method on the basis of prospect theory is developed under interval neutrosophic environment to compare with the method based on regret theory. In the method based on prospect theory, the utility values are denoted by evaluation difference between each alternative and reference point, and the probability weight function is utilized to make a fuzzy stochastic MCDM problem reduce to a fuzzy MCDM problem.
The ranking results of the methods based on prospect theory and regret theory which are shown in Table 5.
It can be seen that ranking results using two methods are identical. Hence, to some extent, the proposed method in this paper is effective and applicable. However, features of these two methods are different and the differences are explained below.
The ranking results of two methods
The ranking results of two methods
Though the decision-making psychology activities are taken into consideration by both of the method based on prospect theory and method based on regret theory, the focus of each method is different. The prospect theory emphasizes loss aversion while the regret theory considers regret aversion. That is, the prospect theory takes the distinction between individual expectation and selected alternative into account. Meanwhile, the regret theory focuses on comparison between the selected alternative and other alternatives to prevent from regret when choosing a bad alternative. In addition, the computational complexity of each method is different. Namely, the number of parameters in each method is not equal. The method based on prospect theory has five parameters while the method based on regret theory has only two parameters. In other word, the regret theory is easier than prospecttheory.
(3) Comparative analysis with extant methods under interval neutrosophic environment
A comparative analysis is conducted between proposed method and fuzzy MCDM methods with interval neutrosophic information.
Since there is no existing research on fuzzy stochastic decision-making problems under interval neutrosophic environment, for the convenience of comparison, we use expected decision matrix to transform fuzzy stochastic MCDM problems into fuzzy MCDM problems. The expected evaluate value edm
ij
for the alternative A
i
regarding criterion C
j
is
Using the expected decision matrix as the evaluation information in fuzzy MCDM problems, and the fuzzy MCDM methods under interval neutrosophic environment are listed below:
In Ye’s method [36], similarity measures between INSs are proposed based on Hamming and Euclidean distances. And the similarity measures between each alternative and ideal alternative are used to rank all the alternatives and obtain the best one. In Chi and Liu’s method [34], maximizing deviation method is utilized to determine the criteria weights. An extended TOPSIS method based on Hamming distance is developed to rank alternatives.
Since criteria weights are completely known in Ye’s method, we use maximizing deviation method to determine the criteria weights in Ye’s method. Further, for comparing conveniently, we utilize Euclidean distance-based similarity in Ye’s method and Euclidean distance in Chi and Liu’s method. The ranking results obtained by different methods are shown in Table 6.
The ranking results of four methods
It can be seen that there are some differences in Table 6. Though alternative A3 is the best one in all of the methods, the ranking orders are inconsistent. The reasons why ranking results are different are presented as follows.
The difference between Ye’s method [36] and the proposed method based on regret theory is the orders of A1, A2, and A4. This is due to Ye’s method [36] only can solve MCDM problems on the premise of complete rationality. Psychological behavior of DMs is not taken into account. By contrast, the proposed method can consider regret aversion ofDMs.
The positions of A1 and A2 are different between Chi and Liu’s method [34] and the proposed method based on regret theory. Though Chi and Liu’s method [34] take both positive and negative ideal point into consideration, it does not consider bounded rationality. Therefore, the ranking results calculated by Chi and Liu’s method [34] are different from those obtained by the proposed method based on regret theory even both of two methods use maximizing deviation method and TOPSIS.
According to the analyses illustrated above, the proposed method in this paper based on regret theory has a lot of advantages which are representedbelow:
The probability in MCDM problems is in a form of interval neutrosophic probability. There are three possible status in the stock exchange market. That is, good, fair, or poor. Interval neutrosophic probability can fully depict the three possible results while classic probability or the fuzzy probability only can describe one result every time. Hence, the proposed method with interval neutrosophic probability is more reasonable and effective. The method proposed in this paper take DMs’ psychology activities into consideration in the decision-making process. Compared with the traditional methods based on complete rationality, the proposed method based on bounded rationally is more likely applied in real-life situations. In MCDM problems, the criteria values are denoted by INSs. As particular cases of neutrosophic sets, INSs can represent the evaluation information perfectly and conveniently in the decision-making process. The maximizing deviation method under interval neutrosophic environment can be used to calculate criteria weights when weight information is completely unknown.
Both fuzzy and stochastic information are existing in real-life decision-making environment. Therefore, FSMCDM methods are studied necessarily to deal with the hybrid information. In this paper, we first proposed interval neutrosophic probability which is derived from NP. Then a novel MCDM method is developed with interval neutrosophic probability based on bounded rationality, in which criteria values are INNs. In the proposed method, maximizing deviation method is used to calculate the criteria weights when weights information is completely unknown. The proposed method is based on regret theory which incorporates TOPSIS to rank the alternatives. Finally, we applied the proposed method in the process of stock selection to verify the availability and applicability of them. Further, we discuss the influences of parameters on ranking results and compare prospect theory with regret theory. The comparative analyses between the proposed method and extant methods with INSs are also conducted.
The proposed method can deal with the evaluation information efficiently and perfectly in stock selection problems with INNs and interval neutrosophic probability. Moreover, interval neutrosophic probability is initially proposed and applied to address MCDM problems in this paper. Subsequently, regret theory are incorporated in proposed method to consider DMs’ psychological preference. Thus, the proposed method have greater advantages than methods based on complete rationality in real-life applications.
In the future, we expect to apply interval neutrosophic probability in some problems which are full of indeterminacy, including the forecast of China’s economic environment, medical diagnosis, and pattern recognition. What’s more, we may use uncertain linguistic variables to represent the probability instead of a specific number or a neutrosophic number. Simultaneously, we could expand the scope of application of regret theory.
Conflict of interests
The authors declare that there is no conflict of interests regarding the publication of this paper.
Footnotes
Acknowledgments
The authors thank the editors and anonymous reviewers for their helpful comments and suggestions. This work is supported by the National Natural Science Foundation of China (No. 71571193).
