A Network Sampling Strategy Inspired by Epidemic Spreading

Algorithm 1

Contact process sampling.

Input: an undirect and unweighted graph ; the sample ratio , where ;
Output: a sample graph , where , and ;
(1)	Randomly select one node , and let and ;
(2)	whiledo
(3)	Randomly select one node from ;
(4)	Select one node from the neighborhood of , with probability inversely proportional to the degree of ;
(5)	;
(6)	end while
(7)	fordo
(8)	if and then
(9)	;
(10)	end if
(11)	end for
(12)	return;