Learning and teaching with technology in the medical sciences
When you attempt to open or import .csv data into Excel, long numbers are helpfully converted into scientific notation. In most situations, this is fine – it make it easier to see the number in a cell and the original number can be seen in full if the cell number format is changed.
However, when numbers are longer than 15 digits, Excel silently rounds anything after the 15th digit – a real problem with GUIDs in general and QuestionMark Perception Question IDs in particular.
There are a number of potential solutions to this, any of which may work for you:
We have been investigating using the Learning Tools Interoperability (LTI) tool available through our VLE, WebLearn (Sakai), in order to authenticate users for various services that we provide (or are considering providing), including Rogo, iCases and OxPro. We initially thought that this would mean we could take user/authentication control completely out of these systems, but unfortunately (in terms of ease, but fortunately in terms of security) it is not so easy.
The LTI specification has been created by the IMS Global Learning Consortium and uses OAuth to sign requests for accessing a tool. The Tool Provider (TP), e.g. Rogo, iCases or OxPro, stores a secret and an ‘oauth_consumer_key’ for each Tool Consumer (TC), e.g. WebLearn. When a tool is launched from the TC through LTI, a signed request is sent to the TP. The TP uses the oauth_consumer_key sent with the signed request to look up the secret, recreate the signature and check that the signatures match. Matching signatures results in a valid request, and the user is allowed to access the tool. If everything within the tool is available to every user this is as complicated as it gets. It is also possible to differentiate access rights based on a user’s role, which should (i.e. it is recommended by the LTI specification) be passed through in the LTI launch data. Both of these scenarios do not require any user information or privileges to be stored by the TP.
The situation gets more complicated when a user should only be allowed to access certain resources within the TP. This is the situation with Rogo, for example, as a student who is allowed to access Rogo should not necessarily be allowed to access every paper within Rogo. Therefore, the Rogo team at the University of Nottingham have implemented LTI in such a way that it is necessary for Rogo to contain it’s own user information. When a user first accesses Rogo through LTI, they must login separately to Rogo. Rogo then stores a link between the user_id passed through in the LTI launch data (which, in combination with the oauth_consumer_key, uniquely identifies the user) and the user within the Rogo system. Thereafter that user should never again need to login to Rogo when coming in through LTI from the same TC.
An LTI link to Rogo only provides a user with access to a single paper. In order to define which paper is linked, the first time an administrator/module convenor (as defined in Rogo) accesses the LTI link (which should be when the link is set up in the TC), they choose the paper from the list of papers for which they are an editor. Thereafter, students coming in through this LTI link will only be able to access that paper (and then only if they are allowed to access that paper within the Rogo system, i.e. they are a member of the module to which the paper belongs).
The situation with Rogo causes problems for us, as we want our students to be able to login using the University of Oxford single-sign-on system (which is used to login to Weblearn), and not need a separate set of login details for Rogo, even if they only need them for their first login. Therefore, we are looking into logging users into Rogo directly through the single-sign-on system, rather than using LTI.
For iCases, we do not want to have to pre-register all users within the system, as is necessary in Rogo. Unlike in Rogo, we are planning only allow access through LTI. We will then create a user profile when a user first accesses the system and this user profile will be linked to the LTI user_id/oauth_consumer_key. WebLearn passes through sufficient information (email address, name, and hopefully single-sign-on username) that we can know who a student is based on this LTI launch data, so we can monitor students’ activity and performance. This information is not required under the LTI specification, but we will make other institutions who use iCases aware that in order to track students’ activity and performance, their TC will need to provide this information, otherwise they will need to find out who a user is based on the user_id passed through in the launch data.
An LTI link to iCases will only allow a student access to a single iCase. If a user wants to access a different scenario, they will have to come in via a different LTI link, with the appropriate resource_link_id. We would prefer not to maintain a list of user/scenario associations, which would enable users to access multiple scenarios through a single link. However, we are still in the early stages of implementing LTI for iCases, and it may be something we choose to do further down the line.
We use Zoomify as part of our CSlide project, to enable viewing of microscope slides scanned at up to 40x resolution. It works in a similar way to Google Maps, loading small image tiles to make up a larger image, without the need to load the entire image (up to 20,000 megapixels!) in one go. This makes it much quicker to load the section of the image that the user wants to look at.
Zoomify have just released an HTML5 version of the viewer, in addition to the Flash-based viewer that has been available since Zoomify was first released. The major advantage of this from our point of view is that it enables microscope slides to be viewed on mobile devices, in particular iPads and iPhones, that do not support Flash. The two viewing options provide a similar viewing experience, but there are a few differences, as follows:
When considering and comparing Rogo and Questionmark Perception, one thing we looked at was the accessibility options available in both. As would be expected both give consideration to accessibility requirements, but the approaches and options vary.
In Rogo, accessibility settings are set for an individual, rather than for an assessment/schedule. Once specified, these settings are used for every assessment that the user sits. The following settings are available:
User’s cannot adjust any settings for themselves within exam delivery, but this is unlikely to be a problem, as accessibility requirements are almost always known about prior to an assessment. Furthermore, they can easily be changed ‘on the fly’.
This year (2011-12), a new course, Biomedical Sciences, started within the Medical Sciences Division. This course combines teaching specific to the course with teaching shared with other courses. In response to this, we wanted to ensure that the students’ experience of the course in WebLearn (Oxford’s Sakai-based VLE) was coherent and personalised, and didn’t require them to search through different parts of WebLearn to find what they needed.
Therefore, we decided to create a portal page that makes it easy for students to access the information – timetables, documents, etc – relevant to them. We wanted the page, and all of the content, to remain in WebLearn, to ensure that managing the content and the users remained straightforward for lecturers and administrators accustomed to using WebLearn.
The resulting portal page, shown above, provided students with a slick, modern-looking page, on which they could see any recent announcements, view their timetable and access documents both relating to their course and from their personal site within WebLearn.
In order to achieve this, it was necessary to create a multi-level structure for the site, with the main site containing a subsite for each year of the course, and each year site containing a subsite for each module.
To dip quickly into the technical aspects, the portal page makes significant use of JavaScript, in particular the JQuery library. Where possible, the content, along with the user’s status and year-group, is gathered using Ajax requests to ‘WebLearn direct’ URLs, which return information, such as a user’s recent announcements, in a computer-friendly format, e.g. JSON. A brief summary of how the different sections of the page are created is given below:
WebLearn’s direct methods are used to get a user’s announcements, specifying the number and age to show. These are then presented to the user in an ‘accordion’, where clicking on an announcement title expands further details of that announcement.
The requirement for the calendar was to bring together multiple module calendars into a single view, with a different colour for each module. This was achieved as follows:
Documents and resources are held in the subsites for each year/module, with some general resources in the top level site. At the time of creating the portal page, there were no direct methods for accessing resources, so a somewhat clunkier method was used. The portal page requests the web view (an HTML page) of the appropriate resources and then uses JQuery to dig down through the folder structure to extract the links to all of the resources and present them in a tree view.
This provides a view of everything in a student’s My Workspace resources folder, produced in the same way as the Course Docs. Students can only view their resources from the portal page – they have to actually go to their workspace to upload/edit resources.
I set about entering some questions in Rogo today which will form the basis of a two part test for school children, testing, from an experimental psychology perspective, their understanding of grammar.
As this was my first foray in to creating a paper, I went at it by using the Rogo documentation – and fell at the second hurdle.
I began by opening “Help and Support” and read with interest the Getting Started with Formative Quizzes and with Summative Exams. Emboldened, I clicked on the link “Making a New Paper” on the latter page – and got a 404 (it does actually work as a link from the Formative Quizzes page though).
In any event, it was good that I applied to Jon because it turned out that I needed to create a complete hierarchy of Faculty, School, Course and Module before I could get into the paper. Once that was created, I set to work on the paper itself and that went swimmingly. I was able to choose between Matrix and Dichotmous questions for what I wanted; I decided I wanted the flexibility of using my own labels and went with the Matrix.
This was very straightforward – my main difficulty was that the text boxes for entering options are rather small. That wasn’t too much of a problem as I was cutting and pasting, but I think that I would find it very frustrating if I was inputting text and was only able to see approximately 11 characters at a time.
I was amused to discover a mis-placed apostrophe as I was entering the questions – and in a test on grammar too!
And then, as I checked the test, I noticed the sign off message:
NOTE: Please complete all questions before clicking ‘Finish’, you will not be able to go back.
We need to get that weak comma changed, I think. I’d like to see a conjunction added so that it reads:
NOTE: Please complete all questions before clicking ‘Finish’, as you will not be able to go back.
Yes, I am being pedantic, I’m afraid. Comes of being an ex-English teacher.
One thing that is clear to me as a user – Rogo is a system that stands on its own merits. For me, conceptualising in terms of “Element A is similar to Element Y in Perception” is not really valid, and just holds me back. I think I need to explore Rogo as an entity rather than as a comparison if its full power is to be understood!
Just been trying out some sample QTIv2.1 questions sent to me by Dr Sue Milne from ELandWeb Ltd which address some issues with maths in online assessment that we have been struggling with for some time:
During our first live test of Rogo, we were somewhat alarmed when the students pointed out that one of the questions was missing an image. Although far from ideal, it was thankfully not disastrous, as it was noticed fairly early on and we were able to print out a copy of the image for all the students.
The question is, what happened to this image? The paper was checked thoroughly against the QuestionMark Perception version of the paper immediately after it was imported, so it would have been spotted at that point had it not come through in the import. However, I clearly did not check the paper thoroughly enough immediately before the exam, as the image was not there.
So the image was lost from the question between it being imported into Rogo and the paper being taken. To find out when and why, I reimported just this question. The image is there in the QTI XML export from Perception, and was there in the question immediately after import. However, after saving the question from the edit screen, without having made any changes to the question, the image had disappeared. The table cell that should contain the image was left just containing an .
We presumed there was something in the imported HTML that was causing this to occur. Initially we thought it might be that there was no closing tag for the <IMG …> (nor a closing slash at the end of the tag), but adding this made no difference, and there were other questions that have the same lack of closing tag and there were no problems with these. On closer inspection of the html for the questions, we noticed that there was a span in the question intro in the faulty question that was not there in any others. This span contained some attributes that came from MS Word:
<SPAN style=”mso-bidi-font-family: Arial; mso-hansi-font-family: Arial” lang=EN-GB><STRONG>diaphragm <BR></STRONG></SPAN>
Removing the span altogether fixed the problem, so we drilled down in order to identify what aspect of the tags was causing it. We looked into the following:
Although it is nice to have found the specific cause, there is no reason for this span to exist at all, so we have removed it completely from the imported version. Hopefully questions containing spans such as this will be few and far between, but since many questions are copied in from Word, care needs to be taken, as it seems that the Rogo text editor, not unusually, does not like them.
For future imports, a quick find/replace through the QTI XML exports when we transfer questions en masse from Perception to Rogo should enable us to remove problematic spans. We will have to do some modification of the XML anyway (e.g. changing the path to images), so it will not be much more work to sort this out as well. I have also blogged about other issues relating to importing questions.
In preparation for our first running our first live test of Rogo, we needed to get an exam paper that had been created in Questionmark Perception into Rogo. This seemed simple enough, simply by exporting the QTI XML from Perception and importing it into Rogo. This generally worked reasonably well, but there were a few issues that had to be dealt with:
Having fixed all these problems, it seemed as though we had an exact copy of the assessment, with everything working as it should. The only difference between the questions as far as the students were concerned was that the multiple MCQ question (there was only one of this type in this paper) was split into 5 separate MCQs.
However, while running the assessment, we were to come across the Curious Case of the Disappearing Image, which, it turned out, was caused by a problem related to importing.