Sequen ial and Pa allel Complexi y
o Lea ning DFA *
José L. Balcáza Josep Díaz Rica d Ga· alda
Dep . Llengua ges i Sis emes In o ma. ics
Uni e si a Poli ecnica Ca alunya
Pau Ga gallo 5, 08028 Ba celona, Spain
Osam·u Wa anabe
Depa n1en o Con1pu e Science
Tokyo Ins i u e o Technology
l !Iegu o-ku, Tokyo 152, Japan
Abs ac . I is known ha he class o de e minis ic ini e au oma. a is poly
no nial ime lea nable by using membe ship and equi a.lence que ies. Ve i n·es
iga e he que y complexi y o lea ning de e minis ic ini e au oma a, i.e., .he
numbe o membe ship and equi alence que ies made du ing he p ocess o lea n
ing. Ve p o e lowe bounds on he numbe o al e na ions be ween membe ship
and equi alence que ies, ancl also show ha a acle-o exis s, allowing us o e
duce he numbe o equi alence que ies a he p ice o inc easing he numbe o
membe ship que ies. Finally, we s udy lea ning in a pa a.llel moclel, he C'RC' V
PRAM. We p o e a lowe bound on he pa allel ime neeclecl o lea ning ancl
design an algo i hm ha asymp o ically achie es his bouncl.
l. In oduc ion
Que y lea ning was in oduced by Angluin [1] and is cu en ly one o he mos impo a.n
models in compu a ional lea ning heo y. I di e s om o he nodels. such as incluc i e
*This esea ch was pa ially suppo ed by he ESPRIT II Basic Resea. ch Ac ions P og a.m o he EC
unde con ac No. 3075 (p ojec ALCOM). The i s h ee au ho s we e suppo .ed in pa by .he DAAD
h ough Acciones In eg adas 1992, 131-B, 313-AI-e-es/zk. The ou h au ho was suppo ed in pa
by Takayanagi Founda ion o Elec onics and Science Technology. E-mail add esses: [email p o ec ed].
[email p o ec ed], [email p o ec ed], [email p o ec ed]
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