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Re: [Ltru] Language tag education and negotiation

From: Mark Davis <mark.davis@icu-project.org>
Date: Sun, 4 May 2008 13:29:06 -0700
Message-ID: <30b660a20805041329u4f5b8857p2a8df402f2a43dcf@mail.gmail.com>
To: "Nicolas Krebs" <nicolas1.krebs3@netcourrier.com>
Cc: www-international@w3.org, ltru@ietf.org
Unfortunately, the specs are ill-defined regarding the q values. Take the
following example:

a, b;q=0.7, c, d;q=0.5, e, f;q=0.9, g

The specs do not distinguish between at least two different possible
reasonable interpretations of what the q values of c, e, and g are:

   1. c;q=1.0, e;q=1.0, g;q=1 // always 1
   2. c;q=0.7, e;q=0.5, g;q=0.9 // always same as previous

Our guess is that the user meant #2, but it is only a guess.

And even once that ambiguity is cleared up, nobody knows what the meaning of
the numbers really is. My native tongue is English, I can understand Swiss
German and German, my French is rusty, and Italian basic. Which of these
should I use?

   1. en, gsw, de, fr, it
   2. en, gsw;q=0.9, de;q=0.9, fr;q=0.8, it;q=0.7
   3. en, gsw;q=0.5, de;q=0.4, fr;q=0.3, it;q=0.2
   4. en, gsw;q=0.99, de;q=0.95, fr;q=0.03, it;q=0.02

All are descending order, but depending on what algorithm the consumer of
the tags uses, they could have very different results. Without being able to
have any consistent expectations for what the q numbers mean, producers of
tags don't know what settings to provide or what difference it will make,
and consumers of tags don't know what the producers meant.

Mark

On Sun, May 4, 2008 at 10:12 AM, Nicolas Krebs <
nicolas1.krebs3@netcourrier.com> wrote:

> Martin Dürst wrote about rfc-822-like-message-header
> "Accept-Language"
>
> >Date: Wed, 30 Apr 2008 14:25:28 +0900
> >To: Asmus Freytag <asmusf@ix.netcom.com>,
> >        Andrew Cunningham <andrewc@vicnet.net.au>
> >From: Martin Duerst <duerst@it.aoyama.ac.jp>
> >CC: www-international@w3.org
> > Archived-At: <
> http://www.w3.org/mid/6.0.0.20.2.20080430142025.0b2154e0@localhost>
>
>
> >Actually, it IS handled by the current scheme, with what's called
> >q-values. Q-values are used to indicate relative preferences from
> >the client side, and relative quality on the server side. So a
> >server could give original documents a q value of 1.0, and translated
> >documents a q-value of e.g. 0.5 (q-values are always between 1.0 and
> >0.0).
> >
> >q-values are sent by some browsers, which translate a preference
> >list of e.g. en, ja, de, fr into something like
> >   en, ja;q=0.9, de;q=0.8, fr;q=0.7
> >or so. Apache also understands them. But they are difficult to set
> >up, so they are not really used much.
>
> And the specification of "Accept-Language" is in rfc 3282 section 3
> urn:ietf:rfc:3282
> http://tools.ietf.org/html/rfc3282#section-3
>
> There is a specification for http protocol only in
> rfc 2616 section 14.4
> urn:ietf:rfc:2616
> http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.4
> http://tools.ietf.org/html/rfc2616#section-14.4
>
>
> The RFC 2616 is currently updated by a working group of IETF and W3C
> http://www.ietf.org/html.charters/httpbis-charter.html
> http://tools.ietf.org/wg/httpbis
>
> If someone has bug-report or improvement about
> http://tools.ietf.org/html/draft-ietf-httpbis-p3-payload-02#section-6.4
> or http://tools.ietf.org/html/draft-ietf-httpbis-p3-payload-02#section-3.5
> ( urn:ietf:draft-ietf-httpbis-p3-payload-02 section 6.4 and 3.5),
> please send feedback to the forum (wich is a mailing list)
> http://lists.w3.org/Archives/Public/ietf-http-wg/ .
>
> See also
> http://www3.tools.ietf.org/wg/httpbis/trac/ticket/13
> http://www3.tools.ietf.org/wg/httpbis/trac/ticket/113
>
>
> _______________________________________________
> Ltru mailing list
> Ltru@ietf.org
> https://www.ietf.org/mailman/listinfo/ltru
>



-- 
Mark
Received on Sunday, 4 May 2008 20:29:44 GMT

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