Family domain experiment 1: results.
MPL
1. ancestor1(X,Y) :- parent(X,Y).
2. father(X,Y) :- ancestor1(X,Y), male(X).
3. mother(X,Y) :- ancestor1(X,Y)), female(X).
4. ancestor(X,Y) :- father(X,Z), ancestor(Z,Y).
4. ancestor(X,Y) :- mother(X,Z), ancestor(Z,Y).
ATRE
1. ancestor1(X1,X2) =. true:- parent(X1,X2).
2. father(X1,X2) =. true:- ancestor1(X1,X2) =. true,male(X1) =. true.
3. mother(X1,X2) =. true :- ancestor1(X1,X2) =. true,female(X1) =. true.
4. ancestor(X1,X2) =. true :- father(X1,X3) =. true,ancestor(X3,X2) =. true.
5. ancestor(X1,X2) =. true :- mother(X1,X3) =. true,ancestor(X3,X2) =. true.
6. ancestor(X1,X2) =. true :- ancestor1(X1,X2) =. true.
It is noteworthy that these results are obtained by using a beam equal to 5.
By enlarging the beam to 15, ATRE learns a theory analogous to that induced
by MPL, namely:
1. ancestor(X,Y):-parent(X,Y).
2. ancestor(X,Y):-ancestor(Z,Y) =. true,ancestor(X,Z) =. true.
3. father(X,Y):-male(X), parent(X,Y).
4. mother(X,Y):-female(X), parent(X,Y).