Query Order

Lane A. Hemaspaandra; Harald Hempel; Gerd Wechsung

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Query Order

Lane A. Hemaspaandra·Harald Hempel·Gerd Wechsung

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Abstract

We study the effect of query order on computational power, and show that $\pjk$-the languages computable via a polynomial-time machine given one query to the jth level of the boolean hierarchy followed by one query to the kth level of the boolean hierarchy-equals $\redttnp{j+2k-1}$ if j is even and k is odd, and equals $\redttnp{j+2k}$ otherwise. Thus, unless the polynomial hierarchy collapses, it holds that for each $1\leq j \leq k$: $\pjk = \pkj \iff (j=k) \lor (j{is even} \land k=j+1)$. We extend our analysis to apply to more general query classes.

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BibTeX RIS

Lane A. Hemaspaandra, Harald Hempel, Gerd Wechsung. 1999-09-30. Query Order. https://arxiv.org/abs/cs/9909020

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