Multiparty Data Publishing via Blockchain and Differential Privacy

Algorithm 2

Mul-LDA-DP algorithm.

	Input: Data sets , , privacy parameters , , random vector and random matrix which are generated in initialization stage, .
	Output: Projection direction vector , projection data
(1)	for to do
(2)	for to 2 do
(3)	Set , data owner generates dimensional random vector , each entry is sampled from
(4)	Compute
(5)	end for
(6)	end for
(7)	Compute
(8)	for to do
(9)	Set , data owner generates symmetric random matrices , each entry is sampled from
(10)	for to 2 do
(11)	Compute
(12)	end for
(13)	Compute
(14)	end for
(15)	Compute
(16)	Compute
(17)	return