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Examples of complex tables in the wild needed

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Reply with quote for those who've been following the growing HTML5 debacle...the latest twist being discussed is the exclusion of table id/headers. instead, some people seem to be proposing creating better heuristics in assistive technology that somehow will magically understand which headings refer to which cell.

i've argued that this is ludicrous, as there's an infinity of possible combinations in complex tables that no AT could resolve through heuristics, but as ever burden of proof has been placed on those arguing against the removal of id/headers to show that there are cases where heuristics would fail. innocent until proven guilty? hmm...

so...does anybody have good examples of complex tables used in the wild? note that they don't necessarily have to have actual id/headers, just need to be very complex and not easily solvable by some simple algorithm that just goes to the leftmost/topmost cell and guesses that that's the heading relating to it.

Patrick H. Lauke / splintered
Reply with quote
redux wrote:
...as ever burden of proof has been placed on those arguing against...
This is a very frustrating trend present in all online technical groups from W3C to Microformats to WHATWG: the core participants inevitably dominate the process. We cannot influence the process because we can't spare the inordinate amount of time needed to get these people out of their entrenched positions.

On the other hand, these activities have to consider a huge range of requests with many factors. Sometimes the suggestions are so naive that it's correct that the proposer be required to find use-cases, gauge feasibility and perhaps make a demo implementation before their proposal can be considered. However, this can make it an uphill battle for valid cases to become recognised.

A balance has to be struck and, after all, they and we are only human.

I am usually given the luxury of recoding tables so they fit into the regular scope model or reformat them using headings, paragraphs and lists. However, I expect webmasters would usually have to work with the arrangement of cells as given to them.

I remember Joe Clark did some tables research for Adobe. He invited people to send in the worst tables they could find, so he might have a ready-made archive of irregular cellular atrocities if you ask nicely.


Last edited by Ben Millard on 25 May 2007 02:58 pm; edited 11 times in total
Reply with quote
redux wrote:
so...does anybody have good examples of complex tables used in the wild? note that they don't necessarily have to have actual id/headers, just need to be very complex and not easily solvable by some simple algorithm that just goes to the leftmost/topmost cell and guesses that that's the heading relating to it.
I don't know about "very complex", but I have quite a lot of tables with their headings in quirky places.

All my examples are eBooks on Project Gutenberg, so unfortunately I can't link you to the HTML directly; you'll need to view source and do a search on <table cos they're big documents.
It also means that "the author shouldn't have arranged their table in that stupid way" doesn't work: the authors are long dead, and I as eBook creator am not at liberty to change their work.
  • Noteworthy Families has some tables that really should have been a long narrow table, but instead that's been chopped in two and joined to make a shorter wider table. Hence headers mid-row.
  • Theory of Storms some heavy maths calculations going on in tables.
  • English Composition has some crazy tables of football teams, in which the headers run down a middle column, and there's tons of cells with rowspan as well. Also a table of baseball statistics ... made me seriously consider using the axis attribute, but couldn't fathom out how, so ended up rendering it as two tables.
  • Lamarck Big table which has sensible column headers, but the rows have no rhyme nor reason whatsoever, there's empty cells and rowspans all over the place; ideally you'd want the table read column by column not row by row.
  • How to live has numerous tables with at least two levels of column headers, and at least one giant table that has two levels of column headers, plus a whole bunch more inserted in between rows.

Warning: many of these date from my pre-accessibility period Embarassed
Reply with quote I'm on the road at the moment (literally), but this is one I keep referring to:
http://broads-authority.gov.uk/boating/navigating/tide-tables.html

Perhaps a point to make would be that current ATs (e.g. JAWs) have actually implemented this, and the example above works well (there are also special keyboard commands for dealing with them).

If they don't support the table markup, you couldn't consider complex tables accessible. If HTML5 doesn't support accessibility, it won't be an acceptable format to use for things like Section 508 or the DDA.
Reply with quote
redux wrote:
so...does anybody have good examples of complex tables used in the wild? note that they don't necessarily have to have actual id/headers, just need to be very complex and not easily solvable by some simple algorithm that just goes to the leftmost/topmost cell and guesses that that's the heading relating to it.


Have you spoken the Joe? Didn't he call for as many complex data tables as possible in the wild a year or so ago for some screen reader testing?
You probably already know but just in case you forgot.
Reply with quote There is a heap of complex tables to be found from this site:
http://www.fedstats.gov/

Steve Faulkner
Technical Director
TPG Europe
The Paciello Group | Web Accessibility Tools Consortium
Reply with quote This is part of the Complex Table Examples thread started by Laura Carlson.

Anne van Kesteren mentions it in the second paragraph of XTech 2007: 5 minutes on HTML5:
Anne van Kesteren wrote:
By the way, I think the latest e-mail from Ian Hickson on complex tables and the one from Maciej clearly shows that we are very much interested in accessibility. I think the WHATWG has developed a different kind of approach to these kind of issues over the years from other people, which may led people to think we don’t give a shit about it or something.
Ian 'Hixie' Hickson is editor of WHATWG's HTML5 proposal. From the end of his message (reformatted with BBcode):
Ian Hickson wrote:
To conclude, I must once again give you my thanks for these links. I'm not sure, however, that they support the argument in favour of headers="" specifically being put in HTML5, given scope="" and the definition it has in HTML5.

Do you agree? If you don't agree, what would be really helpful is an explanation of what it is that headers="" does that scope="" does not.

I can immediately grant you two things:
  1. headers="" is more widely implemented than scope="",
  2. headers="" handles some edge cases that scope="" cannot.
However, in the case of the second of these points, I do not think that we should necessarily optimise for such rare cases, and in the case of the first, I think it would be more helpful to have input from AT authors to explain *why* scope="" hasn't been implemented as widely. Is it simply that AT implementors haven't gotten there yet? Is the HTML4 definition to vague? Does the HTML5 definition help? Is the feature somehow fundamentally flawed?
In HTML5's Forming relationships between data cells and header cells, the algorithm for scope="" is an intuitive interpretation of HTML4's Associating header information with data cells combined with HTML4's specification for scope. HTML5 spells out how it should work and provides a programmable algorithm which removes guesswork and is something implementers could conform to.

Maciej is from Apple and his message is centered on this (reformatted in BBcode):
Maciej wrote:
Hixie wrote:
I can immediately grant you two things:
  1. headers="" is more widely implemented than scope=""
I think this argument is pretty strong, actually. If someone wanted to make table markup that can be understood by screen readers and wished to address older screen readers, it seems like headers="" is the option that degrades gracefully. This seems like a reason to at least specify headers="" as a UA requirement for UAs that associate cells and headers, and possibly a reason to make it conforming for documents so that authors can write conforming HTML5 without leaving out older screen readers. HTML5 goes to some lengths to allow markup that degrades gracefully in older browsers, and it seems reasonable to do this for screen readers as well.
Like, backward compatibility FTW.

(EDIT) I've started making real-world table tests to see if scope really is adequate for the irregular tables which exist in the wild.
  • I'm using Gez Lemon's Table Inspector extension for Firefox as a yardstick.
  • How usable the output would be for a human is something I can't test since I become too familiar with the data whilst recoding.
  • If anyone could run a real AT through the tests please say so here.
  • It's entirely possible that I've cocked up some markup; if you spot mistakes please list them here.
Once there's a decent collection of tables, I'll probably add them to the WHATWG Forum for further discussion and testing.

Nobody has said they contacted Joe Clark, so I sent an e-mail to him and the PDF/UA leader. I found his collection of irregular tables which I have started working through. Laura Wisewell confirmed that recoding Project Gutenburg tables for research purposes should be acceptable use.


Last edited by Ben Millard on 25 May 2007 12:13 pm; edited 5 times in total
Reply with quote Selection of tables from .govt.nz

  • http://www.dol.govt.nz/publications/general/soi2006/21statfinperf.html
  • http://www.msd.govt.nz/publications/statement-of-intent/2007/forecast-financial-statements.html
  • http://www.mfe.govt.nz/publications/about/soi/2007/html/part2/vote-environment.html
  • http://www.linz.govt.nz/publications/statement%2Dintent%2D0607/financial/financial-statements/financial-performance/index.html
  • http://elabs.govt.nz/web-standards/table-ids-and-headers.html
Reply with quote Nice examples, Terrence. More the merrier. Smile

I've had a reply from Joe Clark about examples of data tables:
Joe Clark wrote:
I will get on to this when I get back next week.
I'm guessing "getting back" is from his talk at @media2007. I'm slowly recoding with scope the Table examples for PDF/UA he collected last year to see if it would be adequate.

Last edited by Ben Millard on 24 May 2007 12:29 pm; edited 4 times in total
Reply with quote Considering they are retaining font for WYSIWYG editors (euch!), I don't understand why there is so much resistance to headers?

It isn't the most elegant technique, but it works and is supported now.

Ian Hickson wrote:
> Examples "in the wild":
>
> http://broads-authority.gov.uk/boating/navigating/tide-tables.html

That table could be done using scope="" without sacrificying much, if
anything, in the way of accessibility. I'll take my hat off to you,
however, that really is a real world example that would work.


I'm not clear how Ian thinks scope would do it on the example I authored, is it one of the ones you've had a go at?

Btw, the data is copyright so, be careful if/how you publish it, or search & replace the values.
Reply with quote Yeah, the Tide Table using scope was the first one I had a go at. It looks quite promising because the headers are in fairly regular positions. Having re-read the "Assistive Technology and Tables" section of chapter 6 by Jim Thatcher in Web Accessibility: Web Standards and Regulatory Compliance, it seems scope has a little support in market leading screen readers.

I actually think headers is elegant. It can make complex and irregular tables accessible in cases where scope doesn't cut it, all without rearranging cells.

I've created an e-mail template for spreading this discussion around:
Ben 'Cerbera' Millard wrote:
Subject: HTML5 and the headers="" attribute

Hello [person or entity],

The Web Hypertext Applications Technology Working Group (WHATWG) are proposing to remove the headers="" attribute from HTML. They are keeping the scope="" attribute because this is considered adequate to describe all data tables apart from those they consider too rare. [1]

In [some article you wrote][2] you wrote:

> [A summary you gave about the need for headers="" in irregular data tables.]

Do you find irregular tables to be so rare they are safely ignored?

[1]
<http://www.w3.org/mid/Pine.LNX.4.62.0705172042370.1180@dhalsim.dreamhost.com>
[2] <[URL to the article they wrote, where possible]>

Ben 'Cerbera' Millard
--------------------
http://projectcerbera.com
Feel free to fill this in, send it to accessibility people and summarise their replies here. I've already sent it to:
If you send the template to anyone, please list them here so we don't spam people. Smile I'll keep this message updated.


Last edited by Ben Millard on 06 Jun 2007 09:33 pm; edited 11 times in total
Reply with quote More examples in the wild:

http://daf.csulb.edu/printshop/copying.html
http://www.wisc.edu/about/facts/budget.php
http://www.sa.sdsu.edu/annualreport/success.html

Anne van Kesteren said yesterday,

> If there are lots of tables out there that currently use
> the headers= attribute and end users rely on them I suppose
> the traversal algorithm should take that into account,
> as Maciej suggested earlier. [1]

I asked what qualifies as "lots"? Reply was:

> I don't think we're looking for use cases but actual usage.
> How much content would break if the new algorithm was used
> and headers= was not taken into account. [2]

Best Regards,
Laura

[1] http://lists.w3.org/Archives/Public/public-html/2007May/1154.html
[2] http://lists.w3.org/Archives/Public/public-html/2007May/1152.html
___________________________________________
Laura L. Carlson
Information Technology Systems and Services
University of Minnesota Duluth
Duluth, MN U.S.A. 55812-3009
http://www.d.umn.edu/goto/webdesign/
Reply with quote Ben "Cerbera" Millard wrote:

> I've started making real-world table tests to see if scope really is
> adequate for the irregular tables which exist in the wild.
[snip]
> Once there's a decent collection of tables, I'll probably add them to
> the WHATWG Forum for further discussion and testing.

Have you considered joining the HTML 5 Working Group?

Ian Hickson posted:
> Anyone can actually join the W3C HTML Working Group. I encourage
> everyone interested in the development of HTML5 to take part. If you
> don't take part, and the language develops in a way you don't like,
> then you have but yourself to blame.
>
> Taking part in the group is not a big commitment. You can spend as
> much or as little time contributing; you don't need to read every
> e-mail on subjects you don't care about, you don't need to call in or
> attend face-to-face meetings. In fact, the W3C has stated in the
> group's charter that no binding decisions will be made at meetings;
> you are guaranteed equal say whether you are present or not.

Members get a vote on the issues. The accessibility and standards advocates currently seem to be a minority.

For further info and instructions for joining visit:
http://ln.hixie.ch/?start=1173385976&count=1

Laura
Reply with quote I started the process of joining the HTML WG a couple of months ago, then work got busy. I've resumed the process and am now waiting for step 5. Thanks for reminding me about it. Smile (EDIT: I'm now on the group and blogged about other members.)

lcarlson wrote:
I asked what qualifies as "lots"? Reply was:
Anne Van Kesteren wrote:
I don't think we're looking for use cases but actual usage. How much content would break if the new algorithm was used and headers= was not taken into account.

(Source: Re: Complex Table Examples.)
The Web Authoring Statistics study Ian Hickson did in December 2005 doesn't say the actual numbers for headers, scope and abbr usage. But if he still has them, this would be the biggest study I know of.

I've seen HTML5 advocates informally talk about it being in use a century from now. Rebuilding or retrofitting sites to be more accessible is already happening in the public sector and increases each year as accessibility becomes more high-profile. That makes understanding the use cases very important, imho.
Reply with quote Yeah, I have some photos of insane tables on Flickr:

http://www.flickr.com/photos/joeclark/tags/pdftables/

I have a folder on my machine of examples from real-world PDFs.

My listing of accessible-cinema reviews –

http://joeclark.org/access/cinema/reviews/

– uses every table HTML feature, which added 25K to the page weight for arguably no benefit. Don’t tell Hixie. Yes, headers= is in there.

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