Fig.1

Ensemble learning based on Stacking strategy"

Fig.2

Ensemble Bayesian network construction framework based on Stacking strategy"

Fig.3

Operators for graph search"

Fig.4

Mult-layer naive Bayesian network"

Fig.5

Order graph of four nodes"

Table 1

Statement for threat datafield"

Table 2

States and discretization result of threat data"

Fig.6

Threat assessment process based on Bayesian network"

Fig.7

Threat assessment network learned by EBN"

Table 3

Sensitive analysis for threat level in EBN model"

Table 4

Sensitive analysis for arrive time in EBN model"

Table 5

Comparison of standard dataset score"

Table 6

Comparison of threat assessment dataset score"

Table 7

Difference in inference probabilities in different models for threat level and arrival time under a signle set of evidence"

Table 8

Inference probability difference for threat level and arrival time in different models (five sets of evidence)"

Table 9

Inference probability difference for threat level and arrival time in different models under full evidence"

Fig.8

Spearman coefficient distribution of 20 sets of target threat ranking for different models under a single observation node"

Fig.9

Spearman coefficient distribution of 20 sets of target threat ranking under five sets of test nodes from different models"

Fig.10

Spearman coefficient distribution of 20 sets of target threat ranking under eleven sets of test nodes from different models"

Fig.11

Spearman coefficient of threat ranking in different models with the variation of number of targets"