Key-Value Data Collection with Distribution Estimation under Local Differential Privacy

Algorithm 1

Sampling protocol.

	Input: The set of key-value pairs, padding length .
	Output: Sampled key-value pair , where and
(1)	Generate dummy key-value pairs, whose keys are and values are 0.
(2)	if   then
(3)	Add random different dummy pairs to .
(4)	end if
(5)	Pick one key-value pair uniformly at random from the .
(6)	return Sampled key-value pair .