## 3 Construction of Comprehensive Index System
### Decomposition and Optimization of Indicators  
This section focuses on the problems of redundancy and low recognition in the indicator layer. Each indicator is optimized to meet the basic principles of indicator system construction: independence and testability. Finally, the content of the indicator layer (third level indicators) was determined. After the criteria layer of the evaluation index system is clearly defined, the following problems still exist in the index layer. 1. The recognition of some indicators is relatively low (identification degree refers to the ability and effect of a statistical evaluation indicator in distinguishing the value characteristics of each evaluation unit in one aspect, so it is also called discrimination degree). 2. There are qualitative indicators that are difficult to characterize numerically. 3. There are redundant and overlapping indicators. It could be seen that 1 and 2 violate the measurability principle of the indicator system, and 3 is against the principle of independence. To ensure the measurability of the indicator, it is necessary to enhance the recognition of the indicator or directly remove the indicator with low recognition. A simple and direct method is to use the coefficient of variance of the measured value of the indicator (where the coefficient of variance = Standard deviation/mean) measure the degree of recognition of the index value. For some qualitative indicators that are difficult to quantify, a comprehensive quantitative decomposition method is employed. A single qualitative indicator is decomposed into a plurality of quantifiable and quantitative indicators, such as network handover performance indicators can be jointly characterized by indicators such as signaling overhead, packet loss rate, handover throughput, and handover delay. In order to ensure the independence and simplification of indicators, redundant and coupled indicators need to be processed. Redundancy in this article refers to the degree of conceptual overlap between indicators. For example, the packet forwarding rate of a router is the same as the actual content of the router's concept of port throughput. Therefore, one of them can be deleted when used simultaneously. The coupling degree mainly measures the degree of positive/negative correlation between indicators. Redundant indicators are reduced by adjusting the Comprehensive weight of each indicator in the system, where the comprehensive weight is used to characterize the redundancy and coupling between indicators. The input parameters are shown in Table 2.  
Figure 3: The processing flow of system reconstruction. The correlation weight \(W_{i}^{\prime}\) is calculated by Equation (1). \[W_{i}^{\prime}=\frac{norm(r1,1)}{norm(R,\inf)}=\sum_{l=1}^{n}\left|r_{il}\right| \bigg{/}\max_{j=1}^{n}(\sum_{k=1}^{n}\left|r_{jk}\right|) \tag{1}\]  
Comprehensive weight: \(\tilde{W}_{i}=0.5[(1-W_{i}^{\prime})+W_{i}]\) is sorted according to the size of the comprehensive weight and filtered according to a certain threshold, such as 80%. Therefore, non-critical redundant indicators can be removed. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multicolumn{2}{c}{**Indicator**} & \multicolumn{4}{c}{**Calculation of Correlation Coefficient**} \\ \hline
**Serial Number** & **Weight of Value** & **Measured** & **Value (m Group)** & **Correlation Coefficient Matrix, R** \\ \hline A\({}_{1}\) & \(W_{1}\) & n\({}_{11}\) &... & n\({}_{1m}\) & r\({}_{11}\) &... & r\({}_{1m}\) \\ A\({}_{2}\) & W\({}_{2}\) & n\({}_{21}\) &... & n\({}_{2m}\) & r\({}_{21}\) &... & r\({}_{2m}\) \\... &... &... &... &... &... &... &... \\ A\({}_{n}\) & W\({}_{n}\) & n\({}_{n1}\) &... & n\({}_{nm}\) & r\({}_{n1}\) &... & r\({}_{nm}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 2: The input parameters of comprehensive weight. Figure 4: Comprehensive evaluation index system. Finally, the optimized indicators are mapped to the corresponding elements, and the construction of the comprehensive indicator system is completed.