TABLE 1.

Variable coding.

Variable	Meanings	Coding
X1	Event type	1. Food safety; 2. Occupational poisoning; 3. Infectious disease; 4. Environmental pollution; 5. Medicine and health
X2	Social media discussion volume	Continuous variable
X3	Traditional media coverage	1. 0; 2. 1–5; 3. 6–50; 4. 51–1,000; 5 More than 1,000
X4	Opinion leader	1. Yes; 0. No
X5	Subject of liability	1. Government; 2. Schools; 3. Enterprises; 4. Individual; 5. Mixed
X6	Influenced areas	1. Single city and county; 2. Multiple cities; 3. Multiple provinces
X7	Number of people involved	1. Extremely large; 2. Large; 3. Medium; 4. Small
X8	City size	1. Extra large; 2. Large; 3. Medium; 4. Small
Time	Duration	Continuous variable
Event	Status	1. Death; 0. Censoring