. Author manuscript; available in PMC: 2009 Jan 8.

Published in final edited form as: AIDS Behav. 2008 Feb 1;12(6):964–973. doi: 10.1007/s10461-007-9352-2

Table 2.

Categorization of repeat responders by number of submissions and number of identical detection variables

Participant typology	Number of submissions	Percent of all multiple submissions (N = 627)	Number of all duplicate responders (N = 132)	Percent identical IP, %	Percent personal identifiers duplicated

					0^a, %	1^a, %	2^a, %	3^a, %	4^a, %
Infrequent^b	2–5	36	86.3	68.4	20.2	36.8	25.4	16.7	.9
Persistent^b	6–10	13	7.7	80.0	50.0	10.0	20.0	20.0	0
Repeater^b	11–30	17	3.9	100	40.0	0	0	20.0	40.0
Hackers^b	45–67	34	2.4	100	66.7	0	0	33.3	0

Sum of identical detection variables (password, username, telephone, e-mail) after IP address within each fraudulent account. For example, “0” means none of the personal identifiers matched and “2” means there were two personal identifier that were the same within a multiple submission

Rows represent independent analyses for each participant typology