灰色关联度分析（Grey Relation Analysis，GRA）

Gray Relational Analysis (Grey Relation Analysis, GRA), is a multi-factor statistical analysis method is based on the degree of similarity or dissimilarity between the trends of factors, as a way to measure factors between the degree of association. Therefore, gray correlation analysis, simple terms, that is a gray system, we want to know which one of a project we are concerned by the extent of the relative strength of the influence of other factors, another popular argument is that ETS : we know that certain assumptions and indicators may be related to a number of other factors, then we want to know this indicator is relatively better relationship with which other factors, which factors relative relationship a little weak, and so on, these factors row a sequence to give an analytical result, we can know the indicators we follow, more relevant factors which. Gray Correlation Analysis The calculation of the following steps:

Grey Association Analysis (Grey Relation Analysis, GRA) is a multi-factor statistical analysis method, which is a measure of the degree of correlation between factors based on the similarity or degree of similarity between trends. So, the gray association analysis method, in a gray system, is simply a gray system where we want to understand the relative strength of one of the projects we care about that is influenced by other factors, and then the popular saying is that we assume and know that an indicator may be related to some other factor, So we want to know which of the other factors is relatively more relevant to this indicator, and which factors are relatively weak, and so on, put these factors in order, get an analysis of the results, we know that we are concerned about this indicator, and which of the factors are more relevant. The specific calculation steps for the gray association analysis are as follows:

Grey relation analysis (GRA) is a multi factor statistical analysis method. It is a method to measure the degree of correlation between factors according to the degree of similarity or difference of the development trend between factors. Therefore, the method of grey relation analysis, in a simple sense, is that in a grey system, we want to know the relative strength of a certain project that we are concerned about affected by other factors, and then it is easy to say: we assume and know that a certain index may be related to some other factors, so we want to know that this index is related to some other factors Which other factors are more related to each other, and which one is weaker, and so on. Arrange these factors in order and get an analysis result. Then we can know which of the factors we are concerned about are more related to. The specific calculation steps of grey relation analysis are as follows: