kstructure {kst}

Knowledge Structure

Description

Creates a knowledge structure from a surmise relation or knowledge states.

Usage

  kstructure(x)
  kfamset(x)

Arguments

x

Either an endorelation (see relation) representing a surmise relation, or a set of sets each representing one knowledge state.

Details

The most basic assumption of knowledge space theory is that every knowledge domain can be represented in terms of a set of domain problems Q. Moreover, knowledge space theory assumes dependencies between these domain problems in that knowledge of a given domain problem or a subset of problems may be a prerequisite for knowledge of another, more difficult or complex domain problem. These prerequisite relations are realized by surmise relations, which create a quasi-order between different domain problems. One advantage of these surmise relations is that they reduce the quantity of all possible solution patterns to a more manageable amount of knowledge states. Each of these knowledge states represents the subset of domain problems an individual is capable of solving. The collection of all knowledge states captures the organization of the domain and is referred to as knowledge structure.

kstructure takes an endorelation representing a surmise relation or a set of sets each representing one knowledge state (e.g., one clause of a surmise system) and returns the corresponding knowledge structure. A knowledge structure always contains the empty set and Q.

kfamset does essentially the same but without ensuring that the empty set and Q are included.

Value

An R object of class kstructure.

Note

Note that by default the quotes indicate the fact that the items are represented by characters. For displaying purposes, these quotes may be turned off by setting respective set options (see options).

References

Doignon, J.-P., Falmagne, J.-C. (1999) Knowledge Spaces. Heidelberg: Springer Verlag.

See Also

relation, set, options

Examples

# An endorelation representing a surmise relation
kst <- endorelation(graph=set(tuple(1,1), tuple(2,2), tuple(3,3),
  tuple(4,4), tuple(2,1), tuple(3,1), tuple(4,1),
  tuple(3,2), tuple(4,2)))
kstructure(kst)
# A set of sets representing knowledge states (e.g., clauses of a surmise system)
kst <- set(set("a"), set("a","b"), set("a","c"), set("d","e"), set("a","b","d","e"), 
   set("a","c","d","e"), set("a","b","c","d","e"))
kstructure(kst)
# Turning off the quotes for displaying purposes
sets_options("quote",FALSE)
kfamset(kst)