How is the ISM model analyzed?

One 、 application

ISM It is a system engineering research method , Its function is to study the system structure relationship ; For example, below （ Directed graph ） in , The influence relationship between the elements is known , Now we hope to use the interpretive structure model to sort out various logical structure relationships , For example, find out the hierarchical relationship of each element , At this point, you can use the interpretive structural model .

Two 、 operation

SPSSAU operation

（1） Click on SPSSAU Comprehensive evaluation ‘ISM’ Button . Here's the picture

（2） Drag and drop the data and click start analysis

3、 ... and 、 Case background

A current system is shown as follows , And the corresponding data format is as follows ：

PS: Steps are as follows ：

Four 、 analysis

Put data into analysis box ,SPSSAU The system automatically generates analysis results

1. Adjacency matrix

The above table is ‘ Adjacency matrix ’ Is the input data matrix , It shows the logical influence relationship between elements . Numbers 1 It means that there is an influential relationship between the two elements , Numbers 0 It means that there is no influence relationship between the two elements . The number of the lower right triangle diagonal must be 0, Because I can't influence myself .

in the light of ‘ Adjacency matrix ’, A column is all 0, Then for ‘ Input end ’, That is, it only affects other factors , Not affected by other factors , If a line is all 0, Then for ‘ Output terminal ’, That is, only affected by other factors , Does not affect other elements .

2. Adjacency matrix and identity matrix are added

Add the adjacency matrix to the corresponding identity matrix , Get the upper table matrix . The aim is to get ‘ Reachability matrix ’.

3. Reachability matrix

explain ： Reachability matrix ’ Show whether there is a connection path between elements ;

First of all ： If the number is 1 Means that there is a path from one element to another ;

second ： If the number is 0 Means that there is no path from one element to another .

4. Reachable set, antecedent set and their intersection table

explain ： Combined with the previous step ‘ Reachability matrix ’ Decompose the results in the table above ;

First of all ： Reachable set R, It said ‘ Reachability matrix ’ In the row corresponding to an element , contains 1 Element collection for ;

second ： Look ahead Q, It said ‘ Reachability matrix ’ In the corresponding column of an element , It includes 1 Element collection for ;

Third ： intersection A, It represents a reachable set R And the antecedent set Q Intersection .

5. Hierarchical decomposition

explain ： Last SPSSAU Exhibition ‘ Hierarchical decomposition ’ result , The hierarchical decomposition table shows the hierarchical distribution of each element ; Like in the picture above , Finally, the system can be split into 5 A hierarchical , The elements in each level are listed separately , The graph can be drawn through the hierarchical decomposition diagram .

First of all ： The purpose of hierarchical decomposition is to understand the hierarchical distribution relationship of each element ;

second ： The top level represents the final goal of the system , The lower layers represent It is the reason of the higher level ;

Third ： The bottom layer represents the initial cause of the system , The upper layer is the result of the lower layer .

6. Drawing graphics

SPSSAU Show at the end ‘ Directed graph ’, ‘ Adjacency matrix ’ Graphical display of .