John Krogstie and I wrote an article describing the work on MAPQUAL, as well as the current work on integrated models, quality aspects of these and the case-study in the medical domain. This is my first published article – which I find very enjoyable:) Unfortunately, due to copyright issues I can’t publish the full-text here, however I dare to attach the abstract. The article will be published in Springer Lecture Notes in Business Information Processing (LNBIP) later this year – before summer.  Thanks to John Krogstie who is very supporting and collaborating throughout every aspects of my work!

Integrated Quality of Models and Quality of Maps

Alexander Nossum, John Krogstie

NTNU, Trondheim, Norway

Abstract.

Conceptual  modeling  traditionally  focuses  on  a  high  level  of
abstraction. Even if geographical aspects such as location is included in several
enterprise modeling  frameworks  [26],  it  is not  common  to  have  geographical
aspects  included  in  conceptual  models.  Cartography  is  the  science  of
visualizing  geographical  information  in maps.  Traditionally  the  field  has  not
included  conceptual  relationships  and  the  primary  focus  is  on  a  fairly  low
abstraction  level. Both  cartography  and  conceptual modeling  have  developed
guidelines  for  obtaining  high  quality  visualizations.  SEQUAL  is  a  quality
framework  developed  for  understanding  quality  in  conceptual  models  and
modeling languages. In cartography such counterparts are not common to find.
An  attempt  to  adapt  SEQUAL  in  the  context  of  cartographic maps  has  been
performed,  named MAPQUAL.  The  paper  presents MAPQUAL. Differences
between  quality  of  maps  and  quality  of  conceptual  models  are  highlighted,
pointing to guidelines for combined representations which are the current focus
of  our  work.  An  example  of  such  combined  use  is  presented  indicating  the
usefulness of a combined framework.

[26] = Zachman (1987)

Today (or probably yesterday) an interesting phenomenon appeared on the internet. A teacher in a small town, in an even smaller primary school had published a text on the topic of science. The text was published at the official web page of Moltemyr school and was, well, quite radical in the way we usually think about science. The text is now removed from the official page, but of course Google had cached it, and so did I, and Google is ready to translate it.

In general the motivation of the text was clearly to shed light on the topic of critique of science and that not all “sciences” are necessarily true – and one should have a “built-in” scepticism towards scientific texts and in general any other information. The principle is great – and I support it strongly – one should always have a sense of scepticism towards new knowledge – however, common sense is necessary – neglect and denial are not.

Briefly summarized the text by Trond Baugen critiqued Darwin’s theory, the Big Bang theory and in general the scientific method of measuring time (i.e. C14 dating method). Which is quite bold topics to aim at. Best case scenario could be a revolution in the way we think and perform science! Unfortunately that was not the case. The argumentation of the text was quite ad-hoc, and well, not scientific – which is a bit paradoxial. From my perspective it was clearly a statement of the authors personal belief, lacking of solid arguments, and appeared to me more entertaining than a source of knowledge.

The fact that it was published on the schools official pages quickly got snapped up by several bloggers and twitterers (?), as a response to this social shaking on the web several of the largest news papers in Norway and other large web pages published the story – and well, the witch hunt had started. Of course throughout academia the text was refuted, critiqued, teared apart and mocked. The author was of course also “reviewed” by a storm of critique on being a Christian fundamentalist, creationist, fanatic intelligent designer (?:) and similar.

Personally, well, yeah, I support the witch hunt. However there are two fundamental reasons for my support. (1) It was published on the official web page of a primary school. Which signals that the school has accepted this as information that is suitable to include in the education. (2) The text is extremely one-sided. Highly subjective with a lack of proper argumentation. Every text, especially propositions of radical thoughts, must include an argumentation which discuss and preferably favours the reasonableness of the ideas presented. If not – it is just a subjective idea that potentially is very difficult for others to grasp – or find the reasonableness in.

Another interesting aspect of this is the Internet’s role in this.  Without the internet this text would never, ever, ever, received this much attention. Unfortunately Moltemyr school is clearly not up for this rapid “peer reviewing” of their published material. When they received the attention – they removed the text – and all similar “radical” texts. Well, this is a decision that can be argued in favour of – maybe it was an error that it was published, maybe they got hacked – who knows. And it’s just that! Who knows? Well, not me, because all I see when I go into Moltemyr’s web pages is that they got a new fax-number, then there are some news on the new swimming program, some adventurous adventures – but nothing, not a note even, on the extreme amount of attention they have received the past 48 hours, nothing except removal of the texts.. What is this communicating? Lack of control? Lack of courage? Lack of proper mechanisms for dealing with attention?

Why not admit that an error occurred? If that was the case.

I’m deliberately not going into the discussion on the ideas presented in the text by Trond Baugen – as that is something already done, by several others, and a whole other discussion.

A plea to everyone – especially teachers of any sort: If you have a radical idea that lacks a solid acceptance and argumentation – make a blog – write it there! Do not publish it as part of an educational material – and do not force your personal views on children!

Finally the promised follow-up to the post on data modelling in PostGIS. In this post I will cover how I populated the database using a graphical tool called uDig.

uDig is actually a (lightweight) GIS-tool by the same guys which make PostGIS. It supports for editing and analysis of spatial data. I actually don’t know that much about uDig, but it is easy to use, and fulfilled my needs:)

So. What I needed was to draw polygons from a floor plan. The floor plan was in .jpg format, so useless to “import” directly in the database. So I needed to georefer the floor plan “photo” and draw on top of it. Fairly similar to old map making techniques using aerial photographies to make “abstract” maps.

First the georeferencing. The actual coordinate system and extent of the floor plan wasn’t actually that important. It was nice if it started close to (0,0) and had some extent (and of course scaled 1:1).  Convinced (but not certain) that uDig could handle this I set of and tried to add a layer using Layer-Add .. files and selecting the .jpg file. However that resulted in some obscure error saying; “unrecognized service…” Well, off to Google. After some searching I found that for .jpg’s to be added in uDig, they first need to be georeferenced. To me that sounds a bit strange, as one might want to actually do just this in a GIS tool. So after some more searching I discovered that one could “manually” rough-georeference a .jpg using the world-file format, named .jgw – which in essence; locks one coordinate of the image to a geo-coordinate and defines the extent of the pixels on both axis. So I guessed somewhat on the parameters and came up with a .jgw. And add layer in uDig worked like a charm.

Floor map image in uDig

Secondly I needed to connect to my PostGIS database. This is very, very easy, as expected, since the two softwares are made by the same “team”. Just add layer -> PostGIS -> Type in credentials -> Select tables and you’re off:)

Add layers from a PostGIS database

Then it was time to edit/draw/insert data into the PostGIS database. This is fairly intuitive. I found that enabling “snapping” is very useful, and quite good implementation of this feature in uDig also. However, you need to enable it: “window->preferences->tool->edit tool->snap behaviour” Why hide this? Well, maybe not everyone are interested.. Anyway. Here you can set the snap behaviour and radius to whatever suits your need. I choose “all layers” and found it working surprisingly well on drawing the “route graph” which consists of several “connected” lines.

Enabling snapping in uDig

After some editing the data looked somewhat like this:

Inserted data

Of course the entities (i.e. rows in the DB) have other properties other than their geographic extent. And uDig provides an editor to enable direct editing of these properties. However…. This is where you really experience the short-comings of an open-source, “experimental” GIS-tool.. Not all editors are in place, such as BigDecimal. This is OK, as it is a minor thing and not that much of use. However, when the table has constraints, such as “NOT NULL”, then uDig just breaks, no errors, no confirms, no notices of what is going on. A bit disappointing. Additionally when editing, often the data isn’t commited properly to the database, and some error (again no messages) occurs. Resulting in the layer can’t be rendered and you need to remove it from uDig and add it from the database again. Luckily this isn’t a complex process though:) But a bit annoying. I ended up with using PgAdmin for the non-spatial data management and uDig solely for the spatial data. Which worked quite well despite the annoyancies.

My task was fairly non-complex, for larger tasks I wouldn’t rely on uDig – yet. However the simplicity of the tool is attracting! And for easy, lightweight tasks it is perfect:)