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Endo_rom
Posted on Saturday, July 31, 2004 - 05:20 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

In Romania we have:
Tp/Tp : 5
Tp/Lp : 30
Lp/Tp : 30-80
Lp/Lp : 5
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Steve HO
Posted on Thursday, November 21, 2002 - 11:57 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Thanks Webmaster and Dave. Totally agreed that the setting varies between different systems and may sometimes expanded depending on the nature of the offence. Reason why putting up the question is to draw a comparsion among different systems so as to work out a realistic and commonly accepted number for workload forecast. Any more feedback and comment is most welcome.
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David Fairhurst
Posted on Thursday, November 21, 2002 - 07:56 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

On the UK National AFIS system the default values are:

tp-tp 3
tp-lp 10
lp-tp 15

The system sometimes returns more than the requested number (especially for tp-lp) if the scores are close. For tp-tp we may not get 3 (sometimes we don't get any respondents) because the scores are too low.
Of course we can and do set our own respondent numbers based on experience, importance of the case and quality of the latent etc.

David @:^)
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Webmaster
Posted on Thursday, November 21, 2002 - 07:18 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Steve Ho,

Good questions.

Also, please remember that most AFIS vendors permit agencies to set the candidate list responses to a variable number determined by long-term evaluation of where "hits" occur on the candidate lists for that system. The size of the candidate list may need to be larger or smaller depending on the operational characteristics of a particular system (including the quality of prints fed into the system, the accuracy and time spent on QC/QA of feature extraction, the matching software, etc.).

Also, in some systems a relatively large number of candidates may be returned for TP/LP searches, but LP Examiners "may" stop going down the list near the point where they see a sudden (e.g. 50%) drop-off in matching scores.

The bottom line for many agencies is that the candidate list length is determined by operational experience with their particular system.
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Steve HO
Posted on Thursday, November 21, 2002 - 02:35 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I have been tasked by my boss to find out the size of the candidate list in other AFIS systems. In Hong Kong, our candidate lists for
Tenprint vs Tenprint : 5
Tenprint vs Latent : 1 per finger
Latent vs Tenprint : 20
Your assistance and input is much appreciated.

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