# Two-Sided Matching Decision Method of Electricity Sales Package Based on Disappointment Theory
## 2 Construction of Evaluation Index System for Electric Power Customers and Power-Selling Companies
### Evaluation Index of Power-Selling Company to Users
#### 2.2.2 User Investment Ability  
The user's investment ability can be described from the user's reputation and quality.  
As an intangible asset of enterprises, the reputation of enterprise users has become one of the main sources of user competition. The higher the reputation of an enterprise user, the higher the stability, efficiency, profitability, and growth ability of the user's operation will be, and the greater the social responsibility it will bear. The more it can form strong values in society, the greater its social influence will be [34]. Therefore, power-selling companies can make long-term profits by cooperating with reputable enterprise users and can promote their power-selling packages through their social influence to attract more high-quality electric power customers.  
Enterprise quality is a comprehensive ability of an enterprise to use human, material, and financial resources to complete its business and production activities. It includes the ability to survive, adaptability, competitiveness, development, and innovation. Therefore, enterprise quality is a complex comprehensive organism, which is not only the unity of production and operation factors and their reasonable organization but also the coordination and unity of internal factors and external conditions of the enterprise [35]. The higher the quality of an enterprise user, the stronger the enterprise user's ability to cope with risks and challenges, and the more stable the development will be. The higher the benefit of the cooperation between the power-selling company and the enterprise user, the more inclined the power-selling company will be to cooperate.  
The authors of [36] proposed a method for evaluating investment capacity based on the _TOPSIS_ method. First of all, set an ideal value vector \((x_{ij}^{*},x_{i2}^{*},\ldots,x_{im}^{*})\) for several evaluation objects describing the user's investment ability, which represents the optimal investment ability of the power user. Set the actual value of the evaluation object as \((x_{i1},x_{i2},\ldots,x_{im})\), and the weighted distance between them is \(y_{i}\):  
\[y_{i}=\sum_{j=1}^{m}w_{j}f(x_{ij},x_{j}^{*}),\;i=1,2,\ldots,n \tag{8}\]  
where \(w_{j}\) is the weight coefficient, and \(f(x_{ij},x_{j}^{*})\) is the distance between \(x_{ij}\) and \(x_{j}^{*}\). If \((x_{1}^{+},x_{2}^{+},\ldots,x_{m}^{+})\) is a positive ideal scheme and \((x_{1}^{-},x_{2}^{-},\ldots,x_{m}^{-})\) is a negative ideal scheme, the distance between the evaluation object used to describe the investment ability and the positive ideal points and the distance between the evaluation object and the negative ideal points are respectively shown as follows:  
\[y_{i}^{+}=\sqrt{\sum_{j=1}^{m}w_{j}(x_{ij}-x_{j}^{+})^{2}},\;i=1,2,\ldots,n \tag{9}\]\[y_{i}^{-}=\sqrt{\sum_{j=1}^{m}w_{j}(x_{ij}-x_{j}^{-})^{2}},\ i=1,2,\ldots,n \tag{10}\]  
User investment ability can be expressed as \(C_{i}\):  
\[C_{i}=\frac{y_{i}^{-}}{y_{i}^{+}+y_{i}^{-}} \tag{11}\]  
The larger \(C_{i}\) is, the stronger the power user's investment ability is and the more favorably it can be obtained from the power-selling company.