Table 9.

Notations used in the summarization technique

Notation	Meaning
L	Desired summary length (number of words)
n	Number of tweets considered for summarization (in the
	time window specified by user)
m	Number of distinct content words included in the n tweets
i	Index for tweets
j	Index for preventive terms
x i	Indicator variable for tweet i (1 if tweet i should be
	included in summary, 0 otherwise)
y j	Indicator variable for preventive term j
Length(i)	Number of words present in tweet i
Score(j)	cf score of preventive term j
T j	Set of tweets where content word j is present
P i	Set of preventive terms present in tweet i