======================================================================
David W. Aha
9/27/88 
Comments on the Mushroom Database
======================================================================

I've replaced the original database twice.  
   1. The database was lost due to backup/downtime problems here at
      UCI.  I replaced the database with a version given to me by
      Wayne Iba.  A brief check indicated that it was in good shape.
   2. Jeff Schlimmer, donater of the database, recently mailed me a
      copy of the database, with suitable 1-character acronymns for
      attribute values (the size of the compressed database shrinks
      from 120 to 50k).  

I suspect that several people have had trouble copying the database over
to their locations.  Please let me know if there is any problem in the 
future.

Thanks,
    Dave Aha
=============================================
1. Title: Mushroom Database

2. Sources: 
    (a) Mushroom records drawn from The Audubon Society Field Guide to North
        American Mushrooms (1981). G. H. Lincoff (Pres.), New York: Alfred
        A. Knopf
    (b) Donor: Jeff Schlimmer (Jeffrey.Schlimmer@a.gp.cs.cmu.edu)
    (c) Date: 27 April 1987

3. Past Usage:
    1. Schlimmer,J.S. (1987). Concept Acquisition Through Representational
       Adjustment (Technical Report 87-19).  Doctoral disseration, Department
       of Information and Computer Science, University of California, Irvine.
       --- STAGGER: asymptoted to 95% classification accuracy after reviewing
           1000 instances.
    2. Iba,W., Wogulis,J., & Langley,P. (1988).  Trading off Simplicity
       and Coverage in Incremental Concept Learning. In Proceedings of 
       the 5th International Conference on Machine Learning, 73-79.
       Ann Arbor, Michigan: Morgan Kaufmann.  
       -- approximately the same results with their HILLARY algorithm    

4. Relevant Information:
    This data set includes descriptions of hypothetical samples
    corresponding to 23 species of gilled mushrooms in the Agaricus and
    Lepiota Family (pp. 500-525).  Each species is identified as
    definitely edible, definitely poisonous, or of unknown edibility and
    not recommended.  This latter class was combined with the poisonous
    one.  The Guide clearly states that there is no simple rule for
    determining the edibility of a mushroom; no rule like ``leaflets
    three, let it be'' for Poisonous Oak and Ivy.

5. Number of Instances: 8124

6. Number of Attributes: 22 (all nominally valued)

7. Attribute Information: (classes: edible=e, poisonous=p)
     1. cap-shape:                bell=b,conical=c,convex=x,flat=f,
                                  knobbed=k,sunken=s
     2. cap-surface:              fibrous=f,grooves=g,scaly=y,smooth=s
     3. cap-color:                brown=n,buff=b,cinnamon=c,gray=g,green=r,
                                  pink=p,purple=u,red=e,white=w,yellow=y
     4. bruises?:                 bruises=t,no=f
     5. odor:                     almond=a,anise=l,creosote=c,fishy=y,foul=f,
                                  musty=m,none=n,pungent=p,spicy=s
     6. gill-attachment:          attached=a,descending=d,free=f,notched=n
     7. gill-spacing:             close=c,crowded=w,distant=d
     8. gill-size:                broad=b,narrow=n
     9. gill-color:               black=k,brown=n,buff=b,chocolate=h,gray=g,
                                  green=r,orange=o,pink=p,purple=u,red=e,
                                  white=w,yellow=y
    10. stalk-shape:              enlarging=e,tapering=t
    11. stalk-root:               bulbous=b,club=c,cup=u,equal=e,
                                  rhizomorphs=z,rooted=r,missing=?
    12. stalk-surface-above-ring: ibrous=f,scaly=y,silky=k,smooth=s
    13. stalk-surface-below-ring: ibrous=f,scaly=y,silky=k,smooth=s
    14. stalk-color-above-ring:   brown=n,buff=b,cinnamon=c,gray=g,orange=o,
                                  pink=p,red=e,white=w,yellow=y
    15. stalk-color-below-ring:   brown=n,buff=b,cinnamon=c,gray=g,orange=o,
                                  pink=p,red=e,white=w,yellow=y
    16. veil-type:                partial=p,universal=u
    17. veil-color:               brown=n,orange=o,white=w,yellow=y
    18. ring-number:              none=n,one=o,two=t
    19. ring-type:                cobwebby=c,evanescent=e,flaring=f,large=l,
                                  none=n,pendant=p,sheathing=s,zone=z
    20. spore-print-color:        black=k,brown=n,buff=b,chocolate=h,green=r,
                                  orange=o,purple=u,white=w,yellow=y
    21. population:               abundant=a,clustered=c,numerous=n,
                                  scattered=s,several=v,solitary=y
    22. habitat:                  grasses=g,leaves=l,meadows=m,paths=p,
                                  urban=u,waste=w,woods=d

8. Missing Attribute Values: 2480 of them (denoted by "?"), all for
   attribute #11.

9. Class Distribution: 
    --    edible: 4208 (51.8%)
    -- poisonous: 3916 (48.2%)
    --     total: 8124 instances