RE: Problem with q values in Accept-Language

Hi Mark,
 
Mark Davis wrote: 
 
> Unfortunately, the spec is ill-defined regarding the q values, as > used in Accept-Language (http://tools.ietf.org/html/rfc2616#section-14.4). >>1. Take the following example, where a..g stand for languages:>> 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:>
> c;q=1.0, e;q=1.0, g;q=1   // always 1
> 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.
 
IMHO the spec is clear enough [[
  The quality value defaults to "q=1".
]] http://www3.tools.ietf.org/html/draft-ietf-httpbis-p3-payload-02#section-6.4
 
>2. 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?>
> en;q=1, gsw;q=0.9,  de;q=0.9,  fr;q=0.8,  it;q=0.7
> en;q=1, gsw;q=0.5,  de;q=0.4,  fr;q=0.3,  it;q=0.2
> en;q=1, 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 far 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, in order to meet any 
>expectations.
 
I think your use case is best described by the third option, because q values "represent a relative degradation in desired quality", and you said you strongly prefer English, Swiss German or German while Italian and Frech are best-than-nothing choices.
 
Of course, measuring the exact float number (aka "q value")associated with each variant (for instance, whether the "quality" of the Italian version of a resource is 0.02, 0.8 or 0.001 w.r.t. the English version) should be out of scope for the HTTP specification.
 
Best Regards
 
Javier Godoy
rjgodoy at fich.unl.edu.ar
_________________________________________________________________
¿Aburrido? Ingresá ya y divertite como nunca en MSN Juegos.
http://juegos.ar.msn.com/