getKFringe function

Outer and Inner Fringes of a Knowledge Structure

Outer and Inner Fringes of a Knowledge Structure

Returns the outer or inner fringe for each state in a knowledge structure.

getKFringe(K, nstates = nrow(K), nitems = ncol(K), outer = TRUE)

Arguments

  • K: a state-by-problem indicator matrix representing the knowledge structure. An element is one if the problem is contained in the state, and else zero.
  • nstates: the number of knowledge states in K.
  • nitems: the number of items in K.
  • outer: logical. If TRUE return outer fringe, else return inner fringe.

Details

The outer fringe of a knowledge state is the set of all items that can be learned from that state, such that adding an outer-fringe item to the state results in another state in K,

KO={qKK{q}K}. K^O = \{q \notin K | K \cup \{q\} \in \mathcal{K}\}.

The inner fringe of a knowledge state is the set of all items that have been learned most recently to reach that state, such that deleting an inner-fringe item from the state results in another state in K,

KI={qKK{q}K}. K^I = \{q \in K | K - \{q\} \in \mathcal{K}\}.

Returns

A state-by-problem indicator matrix representing the outer or inner fringe for each knowledge state in K.

See Also

slm, simulate.blim.

Examples

data(DoignonFalmagne7) ## Which items can be learned from each state? getKFringe(DoignonFalmagne7$K) ## Which items in each state have been recently learned? getKFringe(DoignonFalmagne7$K, outer = FALSE)