A Dynamic Privacy Protection Mechanism for Spatiotemporal Crowdsourcing

Algorithm 2

Static publishing anonymity protection based on l-diversity.

	Input: l-diversity parameter l, aggregation result U from Algorithm 1
	Output: aggregation result L
(1)	Take time set T out of U
(2)	Take location set O out of U
(3)	Calculate the global centroid by equation (5),
(4)	whiledo
(5)	,
(6)
(7)	, ,
(8)	for to do
(9)	Update the centroid of by equation (3)
(10)
(11)	, ,
(12)	end for
(13)	Update the centroid of by equation (3)
(14)	,
(15)	end while
(16)	whiledo
(17)	fordo
(18)
(19)	,
(20)	Update the centroid of
(21)
(22)	end for
(23)	end while
(24)	return L