Inverted Index

You can select the engine to be used for screening by specifying it in the Trade Master Data > Screening Service Configuration > Service Preference window.

This engine uses an inverse indexing algorithm for indexing restricted parties by bigrams. This engine uses the occurrence of bigram characters (two characters) in the party and the restricted party data to compare and compute a coefficient value, which in turn is used to determine the match percentage. The output match factor can vary from 0 to 1.

Note: Match direction is not applicable for Inverted Index engine. So even if you select any option from the Match Direction drop-down list on the Service Parameter page, it will not be considered during restricted party screening using this engine.

Matching Factor Calculation by Inverted Index Engine

The Inverse Index engine performs screening using the following process:

1. Split the party and restricted party into bigrams.
2. GTM calculates the match factor between the two parameters using the following formula:

Match factor Formula = [2 * NC/{N1 + N2}]

where,

Number of Bigrams of Party word = N1

Number of Bigrams of Restricted Party word = N2

Number of common Bigrams of Party and Restricted Party word= NC

Example

Party full name: MOHAMED ABU ABDA                       

Bigrams = [MO, OH, HA, AM, ME, ED, AB, BU, BD, DA]

N1 = 10       

Restricted party full name: MOHAMED MUMU

Bigrams = [MO, OH, HA, AM, ME, ED, MU, UM]

N2 = 8

Common bigrams:  [MO,OH,HA,AM,ME,ED]

NC = 6

Match factor = (2*(6))/(10+8) = 0.667