% cd ~ashwin/ml

% cl
Allegro CL 3.0.3.sequent.1 [sequent] (9/21/89 14:29)
Copyright (C) 1985-1988, Franz Inc., Berkeley, CA, USA

<cl> (load "id3.lisp")
; Loading /hydra6/ashwin/ml/id3.lisp.
T 

<cl> (load "weather-data.lisp")
; Loading /hydra6/ashwin/ml/weather-data.lisp.
T 

<cl> (pprint weather-examples)

((- (SUNNY HOT HIGH FALSE)) (- (SUNNY HOT HIGH TRUE))
 (+ (OVERCAST HOT HIGH FALSE)) (+ (RAIN MILD HIGH FALSE))
 (+ (RAIN COOL NORMAL FALSE)) (- (RAIN COOL NORMAL TRUE))
 (+ (OVERCAST COOL NORMAL TRUE)) (- (SUNNY MILD HIGH FALSE))
 (+ (SUNNY COOL NORMAL FALSE)) (+ (RAIN MILD NORMAL FALSE))
 (+ (SUNNY MILD NORMAL TRUE)) (+ (OVERCAST MILD HIGH TRUE))
 (+ (OVERCAST HOT NORMAL FALSE)) (- (RAIN MILD HIGH TRUE))) 

<cl> (id3 weather-examples)

 Feature: OUTLOOK
   SUNNY
     Feature: HUMIDITY
       HIGH
          Class is: -
       NORMAL
          Class is: +
   OVERCAST
     Class is: +
   RAIN
     Feature: WINDY
       TRUE
          Class is: -
       FALSE
          Class is: + 

<cl> (setf *trace-id3* t)
T

<cl> (id3 weather-examples)

Info gain for feature 1 = 0.247
Info gain for feature 2 = 0.029
Info gain for feature 3 = 0.152
Info gain for feature 4 = 0.048

Splitting on feature 1

Considering value SUNNY of feature 1
Info gain for feature 2 = 0.571
Info gain for feature 3 = 0.971
Info gain for feature 4 = 0.020

Splitting on feature 3

Considering value HIGH of feature 3
All examples -

Considering value NORMAL of feature 3
All examples +

Considering value OVERCAST of feature 1
All examples +

Considering value RAIN of feature 1
Info gain for feature 2 = 0.020
Info gain for feature 3 = 0.020
Info gain for feature 4 = 0.971

Splitting on feature 4

Considering value TRUE of feature 4
All examples -

Considering value FALSE of feature 4
All examples +

 Feature: OUTLOOK
   SUNNY
     Feature: HUMIDITY
       HIGH
          Class is: -
       NORMAL
          Class is: +
   OVERCAST
     Class is: +
   RAIN
     Feature: WINDY
       TRUE
          Class is: -
       FALSE
          Class is: +

<cl> (exit)
; Exiting Lisp
%