SDRM-LDP: A Recommendation Model Based on Local Differential Privacy

Algorithm 1

Privacy protection.

Input: ;

Output: The Query Results & New History Records

1: Initialization

2: fordo

3: Sort based on time

4: ifthen

5:  Deleting .

6:  Get new records .

7:  Perturbing History Records

8:  

9:  Get .

10: end if

11: end for

12: Local Differential Privacy

13: Probability of true query result is , add noise for each user.

14:

15:

16: Get the privacy item query result .