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Re: [FYI] Zunehmende Internet-Regulierungsphantasien im BMJ

In schulung.lists.fitug-debate you write:
>> Irgendein Header
>> im HTTP oder Tag im HTML könnte eine Einstufung vornehmen, der 
>> Browser kann nur seiten Anzeigen, die dieses Tag haben. Wahlweise
>> kann auch ein Zwangsproxy dies durchsetzten. 

>das gibts glaube ich schon laenger und heisst PICS http://www.w3.org/PICS/

PICS unterliegt einer Reihe von Einschraenkungen, die es
unmoeglich machen, PICS sinnvoll einzusetzen.


- Third Party Rating cannot be based on URLs

All widely deployed systems for ICR&S are currently using URLs
to identify content and to tie their ratings to such content.
This approach is basically broken because URLs do not map to
content, not even in the case of static content.

For static pages, current webservers offer a lot of facilities
to negotiate the actual content which is being served in
response to a specific URL. In particular, serving language
specific content is very popular. For example, the homepages of
multinational projects (like the Debian Linux project,
http://www.debian.org) are negotiated based on the language
preferences that were expressed with a HTTP request. Also, many
pages serve different content, depending on the IP-address or
domain the request originated from or customize their content
depending on the current time [4].

The problem worsens when it comes to dynamically generated
pages, where the actual webpage which the client receives never
exists on the server, but is created just as it is requested.
The contents of such a page may change from one request to the
next, even if all other parameters are identical. The server may
take any parameters into account when creating the page,
including internal state (memory of previous requests). Because
internal state is kept on the server only, it is impossible to
fully describe all request parameters needed to recreate a
specific content without thorough knowledge of the application
running on that particular server.

But even if we have perfectly static, non-negotiated content,
URLs are inadequate to address content. URLs describe storage
display objects such as images and HTML pages, but content can
be smaller or larger than such pages.

For example, the start page of any portal, news site or
discussion forum contains many small, unrelated articles which
are presented in overview form. Each individual article is a
semantic unit with different properties regarding a rating
system, but with URLs we can only address the whole page and
assign a rating to the entire page.

Conversely, a page or a site may be pieced together from
individual documents which form a greater semantic unit that
deserves a certain rating only when viewed as a whole. This may
be true, for example, for an AIDS information site or a
holocaust memorial site which may contain texts and images that
deserve a very different rating when taken out of their original

HTML provides no mechanism to address subentities of a page or
to address pages collectively. Some extensions to the XML
specification will slightly improve this situation.

[ Der letzte Absatz bezieht sich auf RDF. Dort heisst es
  denn auch in der RDF-Spezifikation


As a result of many communities coming together and agreeing on
basic principles of metadata representation and transport, RDF
has drawn influence from several different sources. The main
influences have come from the Web standardization community
itself in the form of HTML metadata and PICS, the library
community, the structured document community in the form of SGML
and more importantly XML, and also the knowledge representation
(KR) community. There are also other areas of technology that
contributed to the RDF design; these include object-oriented
programming and modeling languages, as well as databases. While
RDF draws from the KR community, readers familiar with that
field are cautioned that RDF does not specify a mechanism for
reasoning. RDF can be characterized as a simple frame system. A
reasoning mechanism could be built on top of this frame system.


7.6. PICS Labels

The Platform for Internet Content Selection (PICS) is a W3C
Recommendation for exchanging descriptions of the content of Web
pages and other material. PICS is a predecessor to RDF and it is
an explicit requirement of RDF that it be able to express
anything that can be expressed in a PICS label. Here is an
example of how a PICS label might be expressed in RDF form. Note
that work to re-specify PICS itself as an application of RDF may
follow the completion of the RDF specification, thus the
following example should not be considered an authoritative
example of a future PICS schema. [ ... ]



>das mag aber niemand so recht, wohl weil immernoch ein
>definitionsproblem der filterkriterien besteht (z.b. was ist
>"offensive nudity" - in den USA duerften z.b. schon H&M-plakate
>unter dieses label fallen, hierzulande nicht).

Wieder aus "Rating does not work":

- Establishing a metric invites a dysfunction

A rating system for content is essentially a metric. The metric
may have one ("suitable for age x") or multiple dimensions
("contains sex x1, nudidity x2, violence x3 and language x4"),
and within one dimension it may be non-ordered ("contains any of
the following: smoking, gambling, drug abuse, violence as a
method of conflict resolution"), ordered ("a violence rating of
3 means that there is more violence in a particular content than
in a content with rating 2"), with discreet or continous values.

A rating system is a cultural code, too, because with the
dimensions and values provided with any such metric comes a
decription on how to interpret and apply them. As a cultural
code, a rating system cannot be objective or valid outside a
specific culture. Specifying the dimensions of the rating
system, for example, defines which issues can be addressed by a
particular rating system. Issues and values outside of the
dimensions of the rating system cannot be addressed, and are
therefore inaccessible to reflective discussion within the space
of the rating system. For the purpose of the rating system, such
issues and values essentially do not exist.

Values within the dimensions of the rating systems can be used
to define proximity relationship if these values are ordered.
Many people tend to think of content that is in close proximity
as being similar, being of similar value, or promoting similar
values. Some content providers insist that their content is not
to be rated with some content rating systems because rating them
with that particular system would place them into the proximity
of other content they do not like, and with which they do not
want to be lumped together [1][2]. For example, both hardcore
pornographic bondage content and a documentation about torture
methods in the holocaust would receive very similar content
ratings within the RSACi rating system. The RSACi system is too
coarse and has no appropriate dimensions to differentiate
between these two types of content. More complex rating systems
raise ease-of-use issues in First Party Rating situations,
though. Also, more context sensitive rating systems raise other
issues, too (see below).

Establishing a metric in a social context and granting rewards
under this metric tends to create dysfunctional social systems.
For example, measuring the efficiency of programmers by
measuring the lines of code produced by them tends to work in
favour of code that has been produced by cutting and pasting
large segments of code. Such code is generally large,
ineffective, and expensive to maintain. Thus, while the metric
provides useful information when used short-term, it tends to
work destructively when used for longer periods of time (Tom
DeMarco, "Why does software cost so much?", Essay 2).
Essentially, degradation begins when the metric is used for a
period long enough to allow for feedback loops.

A classic dysfunctional metric that can be observed on the web
is rating the efficiency of a banner ad on a web page by
counting hits to that banner ad. Using this metric for a longer
time tends to encourage people to put content on their pages
that creates page impressions and to load many banner ads on
such pages. The result is your average free porn page. It also
encourages spamming search engines and the network with ads for
a particular page to increase page impressions. The ultimate
dysfunctional perversion is to load the page with JavaScript
code that opens further pages with banner ads when the user
tries to leave or close the page. While the banner ads are not
recognized by the user, at best, and create a negative image for
the product advertised, at worst, such pages do generate lots of
hits on a counter and are therefore favoured by the metric.

Because cultural and moral values cannot be expressed and
measured directly like volts and ohms, any such metric will show
dysfunctional behaviour and finally invalidate itself when used
for a longer time. Obvious examples are things like exempting
news sites from the requirement to rate content to relieve them
from the burden to provide ratings for rapidly changing pages -
this will provoke providers of content that rates bad under any
given rating system to present their content in the format of a
news site to get the bonus of exemption. Similarly, exempting
web discussion forums from a requirement to provide ratings will
make badly rated sites to adapt and to chose a forum-like

Because of the inability to address cultural or moral values
objectively and outside of the context of a particular culture
or moral system, it would be only logical and very tempting to
create context sensitive rating systems. Context sensitivity
here goes two ways: it may rate a specific content component
within the presentation context, and it may rate specific
content within a specific cultural context.

For example, singular pornographic images may rate bad in a
certain system, but a photomosaic(tm) of girlie-power icon Lara
Croft consisting of lots of such images may rate good within the
same system because of artistic value and the message promoted
by this artwork. So while the individual photo may still rate
bad, in this particular context of presentation it will rate
good. Also, a photo of James Dean leaning against his car and
smoking a cigarette may rate good in some cultural contexts by
showing a celebrity in a pop-art context, and bad in others as
promoting environmentally bad modes of transport and nicotine
drug abuse, depending on the priority of values of the culture
perceiving the image. These priorities may change within the
same culture or even the same recipient, depending on fashion or
even personal mood.

What is more, only the process of filtering content which may
appear as rating bad in a given context may actually create
objectionable content in another context. For example, by
suppressing all images which rate bad in one context there may
be created a pattern that conveys a message of objectionable
content [3].

So while context specific labelling is seductive as a way out of
the dysfunctionality problem, it is also error prone,
unenforceable (Would you please try to rate your web pages
within the cultural context of the Amish People, the values of
the current Nipponese, Spanish and Scandinavic societies?) and
favouring one specific cultural context is of course an act of
culture imperialism. It is also a value rating ("The context
rating on your web page/for our web page in your rating service
implies that you have authority to decide what
Christian/Scientologian/Buddhist/... values are and that our
page is bad according to what you assert these values are.")
with all problems that come with such ratings, including a ton
of liability issues.

- Translating from one metric into another does not work

Different metrics have different underlying cultural and moral
value systems and different assumptions for judgement. Unlike
algebraic spaces, the spaces created by such metrics cannot be
mapped onto each other without loss (sometimes they cannot be
mapped at all). Certain dimensions may not exist in the target
metric and must be emulated. For example, it is impossible to
translate the one-dimensional Video Standards Council metric for
video films ("general viewing", "PG", "R", ...) into the RSACi
(integer numbers between 0 and 4 in each of the categories of
Sex, Nudidity, Violence, and Language), even though the target
systems seems to be more expressive, having more dimensions and

Some proposals offer functionality that can be used to bundle
presets in different rating systems into a single profile. For
example, the PICSRules extension to the PICS system allows a
user to define a single profile that contains an arbitrary
number of selective criteria applied to different PICS compliant
content ratings systems.

A user of such a PICSRule may be able to view content that rates
this-or-that under SafeSurf ratings or such-and-such under RSACi
ratings. Using such a system may create the impression that the
this-or-that SafeSurf rating and the such-and-such RSACi rating
are equivalent and that it is therefore possible to map one
system onto the other. This is a thouroughly false impression.

What does work (in PICSRules) is to bundle arbitrary selective
preferences into a profile, but this profile is in general (and
probably in practice in most cases) not consistent or
well-defined. Consider content that has been rated under two
different rating systems and a majority of reviewers agreed in
both cases that these ratings are correctly applied to this
particular content. Assume further a recipient that is asked to
define a filtering profile for his or her child in both of the
rating systems reflecting the personal cultural values that this
child should be able to expose itself to. Unless the page has a
marginal rating (i.e. totally harmless or totally unacceptable),
it will be common that the page will be rated accessible under
one rating system, but inaccessible under the other, i.e. the
ratings do not functionally map onto each other because of the
different implied cultural values within the metric itself.

>das duefte dazu fuehren das viele anbieter ihre sites in vorauseilendem
>gehorsam gleich viel "schlimmer" einstufen als sie eigenlich sind, um
>rechtliche probleme zu vermeiden.

Das funktioniert nicht, denn siehe "Labeling content that is not
harmful nor prohibited is a requirement but cannot be enforced",
letztere Absatz. (Quote ich hier nicht noch einmal, denn den
habe ich in einer anderen Nachricht bereits zitiert).