RE: EvalTF Size of Sample

Hi Kathy,

This could be related to the barrier probability: would you find more if you look at more pages?
We have to consider how comparable the results will be if we do not use what seems to be the minimum 25 pages.
We will cover barrier probability in a later part of the Methodology.
Kindest regards,

Eric

=========================
Eric Velleman
Technisch directeur
Stichting Accessibility
Universiteit Twente

Oudenoord 325,
3513EP Utrecht (The Netherlands);
Tel: +31 (0)30 - 2398270
www.accessibility.nl / www.wabcluster.org / www.econformance.eu /
www.game-accessibility.com/ www.eaccessplus.eu

Lees onze disclaimer: www.accessibility.nl/algemeen/disclaimer
Accessibility is Member van het W3C
=========================

________________________________________
Van: Kathy Wahlbin [kathy@interactiveaccessibility.com]
Verzonden: woensdag 4 januari 2012 15:44
Aan: Velleman, Eric; public-wai-evaltf@w3.org
Onderwerp: RE: EvalTF Size of Sample

Hi Eric -

I agree with you that the three sample lists should be included.  I think
that the number of pages will vary based on the website purpose, size and
functions.  It will be very difficult to say that you should evaluate at
least 25 pages on every site.

That said, here are the questions that I have:

1.  Should we consider defining the number of pages in a sample based
different scenarios or types of websites?

2.  To defined size, do we need to talk about the number of pages or could
we define it like you have done with the three sample lists and let the
evaluator determine from those lists how many pages should be reviewed?

Kathy

Phone:  978.443.0798
Cell:  978.760.0682
Fax:  978.560.1251
KathyW@ia11y.com



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-----Original Message-----
From: Velleman, Eric [mailto:evelleman@bartimeus.nl]
Sent: Tuesday, January 03, 2012 6:15 PM
To: public-wai-evaltf@w3.org
Subject: EvalTF Size of Sample

Dear all,

We had a short discussion in our last telco about the size of a
representative sample of a website.
The discussion varied between 6 and 5000... How many pages should we have in
a sample to be replicable and at the same time achievable in terms of time
and money?

In the updated version of the Methodology that will be online in the coming
days I added:
- the three sample lists that should be included into an evaluation (core,
task-based and random). If we just take one of every resource named there,
we have at least 25 pages.

Kindest regards,

Eric

=========================
Eric Velleman
Technisch directeur
Stichting Accessibility
Universiteit Twente

Oudenoord 325,
3513EP Utrecht (The Netherlands);
Tel: +31 (0)30 - 2398270
www.accessibility.nl / www.wabcluster.org / www.econformance.eu /
www.game-accessibility.com/ www.eaccessplus.eu

Lees onze disclaimer: www.accessibility.nl/algemeen/disclaimer
Accessibility is Member van het W3C
=========================

Received on Wednesday, 4 January 2012 16:14:15 UTC