I nternational
V irtual
O bservatory
A lliance
Educational Resources in the Virtual Observatory
Version 0.1
Filled in automatically
- Working Group
- Edu IG
- This version:
- filled in automatically
- Latest version:
- not issued outside
EDU-IG
- Previous version(s):
- None
- Author(s):
- Marco Molinaro
Markus Demleitner
Massimo Ramella
Giulia Iafrate
Abstract
The goal of this IVOA Note is to introduce and explain practices followed
and requirements found while creating and
deploying astrophysical resources
dedicated to educational purposes within the standard VO framework.
Issues, proposed solutions and desirables are here reported to be
possibly taken into account in future modifications of relevant
standards.
In detail, we discuss: the curation of educational resources inside or
along with standard registries; use cases and techniques for registering
and locating documents, tutorials and similar within the registries;
dealing with multiple languages.
Status of This Document
(updated automatically)
This is an IVOA Note generated by discussion between Education IG and Registry WG members mainly.
A list of current
IVOA Recommendations and other technical documents can be found at http://www.ivoa.net/Documents/.
Acknowledgements
blah
Introduction
Advances in technology and communications are creating new and exciting
opportunities for teachers to bring astronomy into their
classrooms. As the VO makes science-grade data publicly available and
classroom sets of (suitably) networked PCs are now standard in schools,
exciting projects come within reach of teachers. In order to make things happen
, it is important to disseminate material to help teachers
tap into these resources. These include documented step-by-step
tutorials, use cases explaining how to perform basic astrophysical research
using VO tools and resources, and similar exist in various formats and
have been translated in different languages.
New opportunities also come on the observational side.
There is a growing availability of remotely controlled
telescopes dedicated to education in many countries world-wide, from the
Bradford Robotic Telescope on MountTeide, Tenerife (http://www.telescope.org)
to the radio telescopes of the Radio Physics Lab, IUCAA, Pune
(http://www.ncra.tifr.res.in/rpl). In some cases, educational telescopes are
linked into a network with the aim of guaranteeing the best observing conditions,
including deep sky observations during regular daytime school hours, and
the best instrument for the particular program of interest. Examples
of these networks are iTelescope.net (http://www.itelescope.net) and EuHOU-MW
(http://euhou.obspm.fr/public).
As telescopes enter classrooms more frequently, interest is growing for a
public archive of observations and hence for publishing and curation tools,
together with the basic applications needed to retrieve, display
and analyze data. The VO already includes most of the technology needed
to satisfy the requests of educational observatories. In fact, since several
years, VO, and in particular the European project EuroVO, is devoting part
of its resources to education (http://wwwas.oats.inaf.it/aidawp5). It is
therefore a natural decision for VO to tackle the problem of publishing
educational data in VO archives.
Resource registration for both educational data services and documents
is the most appropriate approach toward making educational resources
available within the VO. While
technically this may seem trivial, keeping too technical
research services out of the the resources devoted to education will
require some effort, that will also be needed in order to avoid contaminating
VO professional research with obviously inadequate material.
In the next section we discuss the idea of educational resources curation, then
Registering Texts we work out the use cases and needs for
registration of tutorials and documents. Finally, we discuss the idea of introducing language
internationalization in the resources.
From a technical point of view the registration of educational services
does not require extensions
to the existing for VOResource standard (std:VOR).
The only real need for investigating changes to what already exists is due to a
use case's distinction between resources to be used in teaching and dissemination
versus all the research driven resources that exist in the VO.
For simplicity here we will distinguish these two groups of resources as
educational and professional but without any intent of putting them
on different levels of importance.
On the one side, teachers and educators may find it difficult to filter out
from all VO resources those that are suitable for their tutorials and
examples. On the other side, educational resources should not be retrieved
by a standard professional query.
Given that it is not a matter of data quality, but only a distinction upon
the resources' scope, nevertheless this duality leads to an issue about the
proper way to tag resources for educational usage.
In the next subsection we propose a possible tagging solution, based upon
the existing ContentLevel element of VOResource, but requiring a small change
to it. The subsequent subsection describes the idea of a
curated registry for educational resources and the reasons for it to exist.
std:VOR already has the ContentLevel element
allowing data publishers to optionally identify their resources as being
suitable for one or more of the following audiences:
- General
- Elementary Education
- Middle School Education
- Secondary Education
- Community College
- University
- Research
- Amateur
- Informal Education
This element turns out to be misused by many publishers, presumably because
it is not really clear what the subtle differences between the available
possibilities are; also, to require a fairly substantial enumeration to
convey "for school use" seems, in retrospect, not likely to promote
widespread adoption. We hence propose to simplify the content model
to:
We expect this to reach two goals:
- to make publishers to better describe (on the average)
their resources
- to providing a tagging solution that suits a first filtering
on the resources at client level
Of course, the chance to
add an
Educational value option to this shrinked list, or even
substitute it to the
General one, would be a valuable change.
This change in the already existing standard will require only
a small effort to update already registered resources because nearly 97% of
them currently have ContentLevel set to research, about 2% of them have
no ContentLevel defined at all and only the remaining have a different value
(or set of values) set for this element (Appendix A details better these
figures).
Until the change in VOResource can be performed, it
can work as a "best practice" recommendation, possibly even at a
registry level, where registries can map existing ContentLevels values
of University to Research and
everything else except Amateur to General.
Even in the case of the simplified ContentLevel tagging system
a curated registry for educational VO resources will be useful for
educators in order to let their students work with a registry without having to
worry about confusing material or overwhelming data sizes. A good example
for this is the educational version of the Aladin sky atlas that has a
built in, curated set of resources suitable for educational level
tutorials.
Curation will require some effort in managing and keeping up to date
such a registry but, most important, it is subjected to some restrictions coming from
the IVOA resource registry architecture.
If such a registry were a standard publishing registry
(std:RI1),
its resources would be harvested by the full registries: this means
that any dedicated educational resource would end up in the full VO
set of resources. For reasons mentioned above, this is not
desirable.
If it were to be a full registry, it will harvest itself all the existing
resources, and not all of them will fit, or be suitable for, the educational
scope the registry has to be preserved for.
We need a resource (the curated, in std:RI1
parlance, local, registry) capable of :
- selectively harvesting the existing VO resources
(e.g. from a full registry);
- register its own educational resources without being directly
harvested by full registries (e.g. this could be done using a
sibling publishing registry dedicated to host those educational
resources that are to be harvested by the standard full registries.
This solution, also presented in Fig. 1, will not touch the existing architecture
while giving flexibility for the emerging educational resources to
be curated.
Educational material is not only about services – text-like material
like tutorials, worked-out use cases, or textbook-like material are at
least as important. Within the VO community, there is a large body of
educational material for a wide variety of audiences ranging from pre-school to
researchers:
- EURO-VO AIDA WP5 - http://wwwas.oats.inaf.it/aidawp5/eng_download.html
- EURO-VO Scientific Tutorials - http://www.euro-vo.org/?q=science/scientific-tutorials
- VAO for Education - http://virtualobservatory.org/education/
To date, such material has been collected informally by the various
projects on plain web pages. It is, in consequence, hard to find, with
knowledge of it often passed on antecdotically. In order to improve upon
this situation, we
propose to keep record of educational material in the registry.
The VO already has a registry extension for standards, which of
course are also text-like (std:STDREGEXT). This extension,
however, focuses on metadata important for standards – e.g.,
vocabularies and status – that is not pertinent for educational
material. Conversely, it is not concerned with document language (which
can safely be assumed to be English for standards), and it disregards
the issue of locating formatted and source version, which for educational
material is important. We therefore propose a simple registry extension
covering text-like material, dubbed DocRegExt.
The design of DocRegExt has been guided by the desire to fulfill the
following use cases:
- Is there a tutorial covering discovering intermediate mass black
holes? (Standard VOResource is sufficient)
- Is there a tutorial covering working with X-Ray data? (Standard
VOResource is sufficient)
- Is there a tutorial dealing with Planets suitable for school use?
(Standard VOResource is sufficient)
- Is there a tutorial dealing with Planets suitable for school use in
Italian? (That requires the declaration of the document language)
- What are the subjects of maintained (in the sense of: probably
working in the VO as found by the students) tutorials?
(The active flag of standard VOResource is
unsuitable here since even outdated resources will still be accessible;
therefore, we introduce the maintained flag)
- Are there tutorials using redshifts? (This is solved by allowing
table metadata in DocRegExt)
- Where can I find an editable version of tutorial ivo://auth/tut1?
(This is solved by allowing multiple access URLs with different content
types, which should be sufficient to allow answering the question)
- Are there translations of tutorial ivo://auth/tut2? (This is covered
by the recommendations on declaring relationships between text-like
resources)
- Is there material using service ivo://auth/svc1? (Again, declaring
relationships covers this use case)
- Is there material about something visible tonight? (In principle,
allowing the coverage element withing DocRegExt resources would allow
answering the question; in reality, few registries expose this
information in useable form)
- I found this VO tutorial somewhere on the net ("on a mirror"). Is it
the latest version? If not, where can I find an update? (Unless the
title of the text changed, standard VOResource should suffice)
On the use cases of locating editable forms of such texts – which
has been found to be necessary fairly regularly – we note in passing
that representing source-product relationships is in principle in the
domain of provenance and thus not in scope for the registry. However, in
the case discussed here the relation is so simple and its representation
so useful that we propose to include it in a DocRegExt.
To satisfy our use cases, we have designed a registry extension with
a single definition, extending the basic vr:Resource
element with three concepts to make the doc:Document
resource type.
The full schema is given in Appendix app:schema
We considered having language as an attribute of accessURL to allow
language-specific document discovery. We decided against this mainly
for reasons of maintainability; the same reason is behind the
recommendation to have both access and source URLs as landing pages.
Since the access URL is supposed to point to a "landing page" anyway,
it is tempting to just unify it with the standard VOResource reference
URL. As a "human-readable document describing this resource"
std:VOR quite conceivably could very well work as a landing
page. For many documents having identical access and reference, urls
will certainly work fine. However, we want to cover the cases in
which different projects offer different translations or even versions
of a document at different sites, which is not possible with just a
single reference URL. A similar reasoning is behind including source
URIs, except that in this case we wanted to allow URIs with non-HTTP
schemes like svn or git.
Document-typed resource records should define relations to other
general resources (e.g. applications, services, ...)
they use; extending the vocabulary of allowed types in VOResource,
we suggest the relationshipType for these relations should be
uses.
TBD: do we want i18n-ed titles?
In the relational registry std:REGTAP, DocRegExt is
entirely represented in the res_details, with details
/language -- A language the document is available in./accessURL -- A URL allowing access to one or more
renderings of the document./sourceURI -- A URL allowing access to an editable version of the document.
Here is a (slightly abridged) example record:
TBD: should we use ISO-3166-1 two letter
country codes or ISO-639-2 two letter language codes?
MMo: I vote for 639-2. This shouldn't require changes now,
but it's better to clarify it in advance IMHO.
Registering text document as VO resources allows search for tutorials and other
materials through standard registry interfaces, but keeping
tutorials up to date, in their master form and also in their translated
versions, is another important issue to allow proficient use.
A versioned repository (using subversion as the version control system)
has been set up at GAVO data center (
http://svn.ari.uni-heidelberg.de/svn/edu/) and collects part of the
already existing VO tutorials with the goal of preserve them and let users
update and translate them in favour of the whole community.
The repository has an internal structure that takes care for:
- different national languages (master language set to english)
- translation vs. master language updates
- licensing, in order to clarify how and whether a tutorial can be changed or re-used
- additional materials used by tutorials
- access roles to allow everyone to access tutorials but prevent untrusted updates or additions to it
The repository is intended to work as a space for cooperative
VO tutorials development.
The EURO-VO AIDA project WP5 produced multilingual tutorials,
meeting the needs for high schools and lower level
educational degrees in countries where English is not the native language.
Clearly, it would be an added value to be able to register an educational or
document resource not only in english (as it is done currently with
standard VO resources) but also in other national languages.
Here we propose discuss whether this means:
- changing VOResource to allow different languages in resource
descriptions;
- enable internazionalization in VO resources within existing
resources: one resource described in multiple languages
- other...
This appendix reports some statistics on the usage of the ContentLevel
element in std:VOR as of 2014-01-30, taken from the
GAVO RegTAP endpoint http://dc.g-vo.org/tap .
There are 14392 useful resources (excluding authorities, standards and
similar) that expose 26 different values as their ContentLevel.
In the following table these values are reported in order of count.
| count | content_level string |
| 13937 | research |
| 290 | |
| 41 | university#research |
| 40 | general#university#research#amateur |
| 24 | university |
| 14 | university#research#amateur |
| 7 | general |
| 5 | research#general |
| 4 | general#research |
| 3 | secondary education#community college#university#research#amateur |
| 3 | research#university#community college |
| 3 | elementary education#middle school education#secondary education |
| 3 | general#university#research |
| 2 | research#university |
| 2 | research#amateur#university#community college |
| 2 | general#informal education |
| 2 | general#elementary education#middle school education#secondary education#community college#university#research#amateur#informal education |
| 1 | university#community college#research |
| 1 | general#university#research#amateur#informal education |
| 1 | elementary education#middle school education#secondary education#community college#university#research |
| 1 | general#secondary education#university#research |
| 1 | university#research#general#informal education |
| 1 | research#university#amateur |
| 1 | elementary education#middle school education#secondary education#community college#university#research#amateur |
| 1 | elementary education#middle school education#secondary education#community college#university#research#amateur#informal education |
| 1 | university#research#amateur#informal education |
| 1 | general#university#research#informal education |
This table can be easily updated from the same endpoint (or an analogue
one) using the following ADQL query:
SELECT
count(*) as cnt, content_level
FROM
rr.resource
WHERE
res_type != 'vstd:servicestandard' and
res_type != 'vg:authority' and
res_type != 'vstd:standard' and
res_type != 'va:application' and
res_type != 'vr:organization'
GROUP BY content_level
ORDER BY cnt DESC
The table shows that only about 1% of the ContentLevel values use
something different and more complex than
research, when
the element is not empty. Morever, of this 1% (165 resources),
61 include the
general value (roughly 37% of them),
29 (17%) state that are devoted to some
education level only,
while 148 (90%) state that are also devoted to some
education level (up to
university).
