Translation Memory Reverse Leveraging

Translation memory reverse leverage is the ability to leverage TM content using the stored target information within a TM entry as if it were the source content, in order to provide translation support from the target language into the source language of the TM entry. In short, the TM reverse leverage operation reverses the source and target designations of segments within a TM entry, thus allowing for translation support of the target language into the source language.

When a TM is leveraged during the leverage process or during the pretranslation process, the system checks to see if the TM has been enabled to support reverse leveraging. If it has, the system first looks for TM entries that were stored for the desired language pair based on the source and target designations within the TM entries. If a qualifying match has not been found, then a reverse lookup is attempted. That is, forward-leverage matches are chosen over reverse-leverage matches from the same TM

If you are leveraging across a TM Group, reverse-leverage matches take precedence over equally scored matches from lesser ranked TMs in the group.

Reverse leveraging differs from "forward" leveraging (the default) in the following ways:

It treats the target language of the match as the source language.
It supports only potential 100% matches. SPICE and ICE matches are not returned as such.
A configurable penalty is assessed to control auto-leverage.
The tm_score_reverse_leverage_penalty TM property in tm.properties can be configured to penalize reverse leveraged matches. The default value is 0. The allowed values must be in the range of 0 to 1. This penalty is a leverage level penalty, and as such, it is applied to the entire match. (Many penalties are applied to the segment element—such as a word or number in the segment—that causes the penalty.) As a result, the impact of the penalty is not affected by the length of the segment. For example, if the penalty is set to 0.02, then the final score will be reduced by 2 percentage points. Based on this value, the maximum score that a reverse leverage match could generate is a 98% score.

The penalty would be applied to all matches resulting from the TM reverse leverage process. However, it will initially only apply to potential 100% and fuzzy matches since the TM reverse leverage process will not initially generate SPICE or ICE matches.

You only need to add the tm_score_reverse_leverage_penalty TM property to the TM properties file when you want to override the default value. This property is currently only supported at the system level. Therefore, the assigned value will be applied to all reverse leverage matches across every TM.

Reverse leverage is useful if you have content in the same subject area being developed in multiple languages. For example, if you have some of your documentation written in English and some written in French, and the subject matter is similar, you could use common TMs for both. Without reverse leverage, only the matches in the direction you are translating to can be used. With reverse leverage, the matches in both directions can be used.

To illustrate this, consider the following example, in which the first TM (TM1) has four English to French segment pairs and one French to English pair, and a second TM (TM2) in this TM group has three French to English pairs (that is, TM2 is a bilingual TM, with entries in only one source language—French. TM1 has reverse leveraging enabled, allowing it to capture both English to French and French to English matches. And, finally, suppose TM1 is the primary TM in the group.

Table 3: TM Contents

TM Name	Source Language	Target Language	Source Text	Target Text
TM1	English	French	The cat in the hat.	Le chat dans le chapeau.
TM1	English	French	The 3 little bears.	Les 3 peu ours.
TM1	English	French	There is nothing like this anywhere.	Il n'y a rien comme ceci n'importe où.
TM1	English	French	Where are all of the children hiding?	D'où tous les enfants se cachent?
TM1	French	English	Les 3 peu ours.	3 little bears.
TM2	French	English	Pourquoi est-ce que tous les enfants se cachent?	Why are all of the children hiding?
TM2	French	English	Trop de cuisiniers dans le pot !	Too many cooks in the pot!
TM2	French	English	Le chat dans le chapeau.	A cat in the hat.

Suppose you translate content from French to English.

The following table compiles the lookup results for a number of search strings.

Table 4: Lookup Results

Lookup Text	100% Matches (R) = Reverse	Preferred Match	Assigned As Reverse Match?	TM Used (and why))
Le chat dans le chapeau.	(R) The cat in the hat. A cat in the hat.	The cat in the hat.	Yes.	TM1 provides a 100% reverse match. The reverse match was available from higher ranked TM, and so the forward match was not accepted.
Les 3 peu ours.	3 little bears. (R) The 3 little bears.	3 little bears.	No. Although a reverse match was available, there was a forward match available from the same TM.	TM 1. TM 1 also provides a 100% reverse match.
Il n'y a rien comme ceci n'importe où.	(R) There is nothing like this anywhere.	There is nothing like this anywhere.	Yes.	TM1.
D'où tous les enfants se cachent?	(R) Where are all of the children hiding? (Fuzzy match) Why are all of the children hiding?	Where are all of the children hiding?	Yes.	TM1.
Pourquoi est-ce que tous les enfants se cachent?	Why are all of the children hiding? (Fuzzy match) (R) Where are all of the children hiding?	Why are all of the children hiding?	No.	TM2.

This example applies the following leverage rules: Reverse leverage matches are ranked below other equally scored matches from the same TM. Forward or normal leveraged exact matches are ranked higher than reverse leveraged exact matches from the same TM. The same holds true for equally scored fuzzy matches.

Note the following about reverse leverage in the WorldServer Browser Workbench. :

The TM entries page from the Browser Workbench displays both normal and reverse leveraged matches. For example, if you perform a TM lookup in the Browser Workbench, you might see the following:

Figure 24: TM Lookup with Reverse Leverage

The reverse lookup icon (

) identifies the matches that result from a reverse leverage search. There is also a tooltip for the icon providing additional information.