Table 4.

Discovering rules from a disease dictionary

	Dictionary			Lookup performance
Iter.	Ambiguity	Variability	Rule	Precision	Recall
0	1.001	2.794	(convert capital letters to lower case)	0.994	0.158
1	1.002	2.747	‘,’ → ‘’	0.989	0.184
2	1.002	2.667	‘ nos’ → ‘’	0.986	0.216
3	1.003	2.609	‘[x]’ → ‘’	0.985	0.263
4	1.003	2.580	‘o’ → ‘’	0.982	0.275
5	1.003	2.554	‘ies’ → ‘y’	0.983	0.291
6	1.003	2.529	‘ ’ → ‘-’	0.984	0.305
7	1.003	2.504	‘-’ → ‘;’	0.984	0.317
8	1.003	2.484	‘e’ → ‘i’	0.985	0.332
9	1.004	2.472	‘iasi’ → ‘rdir’	0.986	0.336
10	1.004	2.459	‘’s’ → ‘’	0.986	0.345
11	1.004	2.449	‘s’ → ‘z’	0.986	0.347
12	1.004	2.448	‘;(nz)’ → ‘’	0.986	0.347
13	1.004	2.447	‘kidniy’ → ‘rinal’	0.986	0.347
14	1.004	2.446	‘pulmnary’ → ‘lung’	0.986	0.347
15	1.004	2.443	‘ir’ → ‘ri’	0.986	0.348
16	1.004	2.441	‘aimia’ → ‘imiaz’	0.986	0.349
17	1.004	2.439	‘[d]’ → ‘’	0.986	0.349
18	1.004	2.436	‘aimlytic;animiaz’ → ‘imlytic;animia’	0.986	0.351
:	:	:	:	:	:
24	1.004	2.427	‘z;thi’ → ‘’	0.986	0.354
:	:	:	:	:	:
31	1.004	2.420	‘z;’ → ‘/’	0.986	0.355
32	1.004	2.348	‘/’ → ‘;’	0.987	0.377
33	1.004	2.348	‘dizrdri;liv’ → ‘livri;dizrd’	0.987	0.377
:	:	:	:	:	:
38	1.004	2.345	‘uding’ → ‘’	0.987	0.378
:	:	:	:	:	:
42	1.005	2.343	‘zufficiincy’ → ‘cmpitinci’	0.987	0.380
:	:	:	:	:	:
50	1.005	2.339	‘(in;zputum)’ → ‘in;zputum’	0.987	0.381
:	:	:	:	:	:
57	1.005	2.335	‘iincy’ → ‘’	0.987	0.382
:	:	:	:	:	:
70	1.005	2.333	‘[idta]’ → ‘’	0.987	0.385
:	:	:	:	:	:
89	1.005	2.327	‘ph’ → ‘f’	0.987	0.387
:	:	:	:	:	:
93	1.005	2.325	‘ci’ → ‘x’	0.987	0.388
:	:	:	:	:	: