Surface structure and deep structure

By Gordon Rugg

The concepts of surface structure and deep structure are taken for granted in some disciplines, such as linguistics and media studies, but little known in others. This article is a brief overview of these concepts, with examples from literature, film, physics and human error.

The core concept

A simple initial example is that the surface structure of Fred kisses Ginger is an instantiation of the deep structure the hero kisses the heroine. That same deep structure can appear as many surface structures, such as Rhett kisses Scarlett or Mr Darcy kisses Elizabeth Bennet.

There are various ways of representing surface and deep structure. One useful representation is putting brackets around each chunk of surface structure, to clarify which bits of surface structure map onto which bits of deep structure; for example, [Mr Darcy] [kisses] [Elizabeth Bennet].

Another useful representation shows the surface structure mapped onto the deep structure visually. One way of doing this is as a table, like the one below.

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Explosive leaf level fan out

By Gordon Rugg

Often in life a beautiful idea is brought low by an awkward reality. Explosive leaf level fan out is one of those awkward realities (though it does have a really impressive sounding name, which may be some consolation).

So, what is it, and why is it a problem? Can it be a solution, as well as a problem? These, and other questions, are answered below.

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Guest Post: Representing lesson structure graphically

By Gavin Taylor

Lesson structure can be seen as a core aspect of teaching; the method in which lessons are planned can influence the whole learning process. Most teachers plan the structure of their lessons using a few well established techniques. One is a three level approach commonly known as a traffic light sequence, as shown below.

figure1 v4

This traffic light system can be used for assessing pupil progress and for differentiation of tasks, as well as clearly showing the lesson structure. This system however has various limitations. For example, this system implies that unless a pupil “moves” from one colour to another, progress has not been made, even though the pupil’s understanding may have been deepened. The criteria for progress also have to be correct; a pupil could, for example, achieve the red objective in the figure above without completing the amber, as these may not be progressive objectives.

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Representing argumentation via systematic diagrams, part 1

By Gordon Rugg

This article is a short introduction to some basic principles involved in representing argumentation, evidence and/or chains of reasoning using systematic diagrams.

This approach can be very useful for clarifying chains of reasoning, and for identifying gaps in the evidence or in the literature.

As usual, there’s an approach that looks very similar, but that is actually subtly and profoundly different, namely mind maps. That’s where we’ll begin.

A mind mapSlide1

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An introduction to graph theory

By Gordon Rugg

Graph theory is an extremely powerful approach that is based on a handful of elegantly simple concepts. It was invented by Euler in the 1740s, and is a central part of modern mathematics and technology. Among other things, it plays a key role in handling traffic on the Internet.

It’s invaluable for representing knowledge, because it combines flexibility with formalism. In particular, it’s useful for representing different facets and viewpoints; for representing hierarchies of goals and values; for representing successive layers of explanations; and for formal taxonomies. Continue reading

An introduction to facet theory

By Gordon Rugg

This is a brief overview of an invaluable concept. It links closely to graph theory, which we describe in another recent article, and to laddering, which we will describe in a later article. All three of these concepts are powerful, simple and elegant, and all three are not as widely known as they should be.

Facet theory in the strict sense is a concept from librarianship and information science. The core concept is that you use several different ways of categorising the things that you’re categorising. This lets you organise the same set of entities in different ways for different purposes. Continue reading