1. Teaching a machine a simple taxonomy
Scott Doherty

2. What's a Taxonomy?
A taxonomy is a hierarchy of objects organized in a type / subtype tree through the ”is-a” relation.

3. Why is this hard? Multiple taxonomies Data modeling
Overlapping classes– degenerates to graph
Multiple inheritance
Relations – which ones?
Top down vs. Bottom up

4. Multiple taxonomies Linnaean taxonomy Sea, Land, Air Beasts
Ad hoc taxonomies

5. Data Modeling How do we represent a thing?
Attribute Value List <K,V>
Propositionalized Attributes 0,1
Database Schema
Inheritance – Java like (I get what my parents have, but I don't show you that)

6. Multiple Inheritance
Multiple inheritance is where a class is the descendant of two classes
This is a graph and not a tree

7. Solution: duplication
Now a strict hierarchy but we don't have a unique path to every object
Space requirements and pedigree tracing are hard

8. The Program A basic ontology Cars, baskets, balls
Red things, blue things, green things
Basic relations
Sub type – more detail, more specific
Super type – less detail, more general
Instance – same attribute list

9. Code – classes: agent (defclass agent () (
(name :accessor agent-name :initarg :name)
(base-types-of-things :accessor agent-base-types-of-things :initform () :initarg :base-types-of- things)
(base-relations :accessor agent-base-relations :initform () :initarg :base-relations )
(learned-types-of-things :accessor agent-learned-types-of-things :initform () :initarg :learned- types-of-things )
(learned-relations :accessor agent-learned-relations :initform () :initarg :learned-relations ) )

10. Code – classes: thing (defclass type-of-thing() (
(name :accessor type-of-thing-name :initarg :name)
(attributes :accessor type-of-thing-attributes :initform () :initarg :attribures ) )
(defclass thing () (
(name :accessor thing-name :initarg :name)
(attributes :accessor thing-attributes :initform () :initarg :attribures)

11. Code - relations
(defmethod is-sub-class-of-type((newtype type-of-thing)(a agent) &Aux known-types)
(setf known-types (agent-base-types-of-things a))
(setf new-type-attributes (type-of-thing-attributes newtype))
(dolist (thing (agent-base-types-of-things a))
(setf newlist (getKeys (type-of-thing-attributes newtype)))
(setf knownlist (getKeys (type-of-thing-attributes thing)))
(setf flag (subsetp knownlist newlist :test 'equal)) ;returns t only if list1 is a subset of list2
(if (equal flag nil)
(format t "not a sub-class~%")
(format t "is a sub-class~%") )

12. Demos Break 2 [3]> (demoPredicateSuperSet) Learning agent ...
name = Taxonomizer 2000
classes ...
2DSHAPE
((ANGLES . 3) (SIDES . 3) (NAME . 2DSHAPE))
relations ...
IS-INSTANCE-OF-TYPE
IS-SUPERCLASS-OF-TYPE
IS-SUBCLASS-OF-TYPE
CHECKING IF new item IS AN INSTANCE OF OBJECT known item
===========================================comparing
base object to compare
new object to compare
((ANGLES . 4) (SIDES . 4) (COLOR . RED) (NAME . 2DSHAPE))
base type size 3
new type size 4
set difference NIL
is an instance
=========================================== finished comparing
NIL

13. Where am I? Can create objects with their attributes (data modeling)
Can check if a thing is a sub-type, super-type or instance of another type of thing (relations)
Have run into the multiple inheritance problem, and am working on how to organize tree structure