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Re: Data Tables using superscript and footnotes

From: devarshi pant <devarshipant@gmail.com>
Date: Mon, 1 Aug 2011 11:35:36 -0400
Message-ID: <CAJGQbjuaeZmN1xCG=g-ZCAHchp=0BeqDr5QzMxtOpc2-KDEHkQ@mail.gmail.com>
To: christopher.a.hoffman@gmail.com
Cc: w3c-wai-ig@w3.org
Thanks, Chris and George. I am copying the list with the feedback you
provided hoping that the group members will find these useful.


Hi Devarshi,

On Wed, Jul 27, 2011 at 12:25 PM, devarshi pant <devarshipant@gmail.com>

> I have a question on data tables that utilize superscripts and associate
them with footnotes. This stems from a recent review of annual reports
containing different superscripts (appended to column headers within <sup>
tags) and footnotes (within <tfoot>). These tables are large and run into

TFOOT is reserved for column headings, basically repeating the
information in THEAD. Therefore is seems that a list of footnotes
should appear at the end of the TABLE, after the closing </table> tag.

> 1.       Display the superscript as a link and load the footnote
information in a pop up (note: an accessible pop up). This would preserve
the tab order after the user closes the pop up, and allow the user to
continue with table navigation

Similarly, you could link each superscript to a footnote somewhere else on
the page, and then at the end of each footnote have a "return to table"
link. This would be programmatically simpler, and would also maintain the
footnotes on printed pages.

DP: A good suggestion. However, not sure if linking a footnote somewhere
else on the page would preserve the focus when a user returns to the parent.

> 2.       Provide instructions before the table. Explain each superscript
association with its footnote as a list item. Put this info below a header

This seems like a simple enough solution, but I think readers' memory for
associations between column headings and footnotes could quickly become
overwhelmed. It's better to have the footnotes be accessible from each

DP: You are correct, users may find it difficult to memorize. I think
magnification users may find it useful before the table.

> 3.       Display the superscript as a link but style it as plain text. Use
a blank href attribute on the superscript, and supply footnote as the title

What would be the point of the superscripts being links with blank hrefs?
And title attributes are for optional advisory information, and are a) often
not seen by sighted mouse users, who don't know they are there, b) often not
read by screen readers, and c) generally inaccessible to keyboard users.

DP: With links with blank hrefs styled as plain text, a screen reader can
access the footnote information. JAWS announces the table header followed by
title attribute which is supplied to the superscript. I think this hoodwinks
sighted users but serves screen reader users. The question is how do we make
a decision on whom to help? In this case, a sighted user can get to the
footnotes and by scrolling up/down and visually make an association. I think
it is reasonable to implement something that allows a screen reader user to
hear the association when the focus is on the data cell. Other factors
(verbose title attribute, JAWS preferences etc) make this suggestion more /
less accessible.

You might also consider aria-describedby, although support might not be
great. Used in conjunction with #1 above, though, it could provide some
important contextual information for the links.

DP: I have to see aria working in conjunction with superscripts as links.


Another response from George Kerscher is quoted below:


I understand that these are published in HTML, but I would hope that this
type of content is produced in EPUB moving forward. In the EPUB 3 spec (
www.idpf.org) we are recommending the use of HTML5 with semantic tagging,
i.e. epub-type that includes semantics used in publishing, e.g. footnotes
and footnote references.

There are many semantic elements used in publishing that go way beyond HTML
and I hope this will become more relevant for published documents.
EPUB 3 Structural Semantics Vocabulary



Received on Monday, 1 August 2011 15:36:03 UTC

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