Risk level

Namely

Mild

Dangerous

Extremely dangerous

Cluster center

0.1802

0.3242

0.5205

0.6388

Event

S5, S9, S12, S14, S17, S19

S3, S6, S7, S10, S11, S15, S18, S20

S1, S2, S8, S16

S4, S13