MODEL CONSTRUCTION APPARATUS, ESTIMATION APPARATUS, MODEL CONSTRUCTION METHOD, ESTIMATION METHOD AND PROGRAM

1 . A model construction apparatus comprising:

a processor; and

a memory storing program instructions that cause the processor to:

receive pieces of observed data from a communication network system that is a target for estimation of a location or a cause of an abnormality;

divide the received pieces of observed data into a plurality of clusters according to types of information represented by the respective pieces of observed data;

determine, for each location or each cause of an abnormality, a representative value as representative observed data for each of the plurality of clusters; and

construct, using the representative observed data, a first causal model for estimating the location or the cause of the abnormality from the pieces of observed data based on a rule-based method.

2 . The model construction apparatus according to claim 1 , wherein the program instructions further cause the processor to:

calculate a value representing a relationship between pieces of observed data when the communication network system is in a normal state among the received pieces of observed data;

calculate, using the value representing the relationship, a first conditional probability representing a relationship between a location or a cause of an abnormality in the communication network system and the pieces of observed data when the communication network system is in the normal state;

calculate, using pieces of observed data when the communication network system is in an abnormal state, a second conditional probability representing a relationship between the location or the cause of the abnormality and the pieces of observed data when the communication network system is in the abnormal state, based on a data-driven method; and

construct a second causal model for estimating the location or the cause of the abnormality from the pieces of observed data, using the first conditional probability and the second conditional probability.

3 . The model construction apparatus according to claim 2 , wherein the program instructions further cause the processor to construct a third causal model by modifying the first causal model based on the second causal model.

4 . An estimation apparatus comprising:

a processor; and

a memory storing program instructions that cause the processor to:

receive pieces of observed data from a communication network system that is a target for estimation of a location or a cause of an abnormality;

store, into the memory, a causal model for estimating the location or the cause of the abnormality, the causal model including a first causal model constructed based on a rule-based method, a second causal model constructed based on a data-driven method, and a third causal model combining the first causal model and the second causal model; and

estimate, using the pieces of observed data, a location or a cause of an abnormality in the communication network system based on one of the first causal model, the second causal model, or the third causal model stored in the memory.

5 . A model construction method comprising the following executed by a computer:

receiving pieces of observed data from a communication network system that is a target for estimation of a location or a cause of an abnormality;

dividing the received pieces of observed data into a plurality of clusters according to types of information represented by the respective pieces of observed data;

determining, for each location or each cause of an abnormality, a representative value as representative observed data for each of the plurality of clusters; and

constructing, using the representative observed data, a first causal model for estimating the location or the cause of the abnormality from the pieces of observed data based on a rule-based method.

6 . (canceled)