Research output: Contribution to journal › Article › peer-review
Probabilistic input-driven pushdown automata. / Розе, Алексей Николаевич; Охотин, Александр Сергеевич.
In: Information and Computation, Vol. 305, 105312, 06.2025.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Probabilistic input-driven pushdown automata
AU - Розе, Алексей Николаевич
AU - Охотин, Александр Сергеевич
PY - 2025/6
Y1 - 2025/6
N2 - A probabilistic variant of input-driven pushdown automata (IDPDA), also known as visibly pushdown automata, is introduced. It is proved that these automata can be determinized: an n-state probabilistic IDPDA that accepts each string with probability at least λ+δ or at most λ−δ, for some isolated cut-point λ∈[0,1] with δ>0, is transformed to a deterministic IDPDA recognizing the same language, with at most (1+[Formula presented])n2−n states and at most |Σ+1|⋅(1+[Formula presented])n2−n stack symbols, where Σ+1 is the set of left bracket symbols in the alphabet. An asymptotically close lower bound is provided: for infinitely many n, there is a probabilistic IDPDA with 2n+3 states and n stack symbols, and with δ=[Formula presented], such that every equivalent deterministic IDPDA needs at least 7n2/14 states and at least n stack symbols. A few special cases of automata with reduced determinization complexity are identified.
AB - A probabilistic variant of input-driven pushdown automata (IDPDA), also known as visibly pushdown automata, is introduced. It is proved that these automata can be determinized: an n-state probabilistic IDPDA that accepts each string with probability at least λ+δ or at most λ−δ, for some isolated cut-point λ∈[0,1] with δ>0, is transformed to a deterministic IDPDA recognizing the same language, with at most (1+[Formula presented])n2−n states and at most |Σ+1|⋅(1+[Formula presented])n2−n stack symbols, where Σ+1 is the set of left bracket symbols in the alphabet. An asymptotically close lower bound is provided: for infinitely many n, there is a probabilistic IDPDA with 2n+3 states and n stack symbols, and with δ=[Formula presented], such that every equivalent deterministic IDPDA needs at least 7n2/14 states and at least n stack symbols. A few special cases of automata with reduced determinization complexity are identified.
KW - Finite automata
KW - Input-driven automata
KW - Probabilistic automata
KW - State complexity
KW - Visibly pushdown automata
UR - https://www.mendeley.com/catalogue/15354502-e41a-3245-ae7e-ab151725b457/
U2 - 10.1016/j.ic.2025.105312
DO - 10.1016/j.ic.2025.105312
M3 - Article
VL - 305
JO - Information and Computation
JF - Information and Computation
SN - 0890-5401
M1 - 105312
ER -
ID: 135908624