The Experts below are selected from a list of 123 Experts worldwide ranked by ideXlab platform
Jaume Casasnovas - One of the best experts on this subject based on the ideXlab platform.
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IPMU - A Deduction Rule for the Approximated Knowledge of a Mapping
Lecture Notes in Computer Science, 1993Co-Authors: Jaume CasasnovasAbstract:The partial knowledge of a valuation, whose values are in the boolean algebra {0,1} may be represented by the utilization of a set of four elements([1]). The partial or approximated knowledge of a valuation or a possibility or necessity measure, whose values are in the real interval [0 1] may be represented by the set of “subintervals” and it is possible to define operations that also generalize the structures of algebra defined by Belnap. In this paper we propose the formulation of the “Deduction Rule” that allows us to deduce valid approximations from the available data.
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a Deduction Rule for the approximated knowledge of a mapping
International Conference Information Processing, 1992Co-Authors: Jaume CasasnovasAbstract:The partial knowledge of a valuation, whose values are in the boolean algebra {0,1} may be represented by the utilization of a set of four elements([1]). The partial or approximated knowledge of a valuation or a possibility or necessity measure, whose values are in the real interval [0 1] may be represented by the set of “subintervals” and it is possible to define operations that also generalize the structures of algebra defined by Belnap. In this paper we propose the formulation of the “Deduction Rule” that allows us to deduce valid approximations from the available data.
Samuel R Buss - One of the best experts on this subject based on the ideXlab platform.
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The Deduction Rule and linear and near-linear proof simulations
Journal of Symbolic Logic, 1993Co-Authors: Maria Luisa Bonet, Samuel R BussAbstract:We introduce new proof systems for propositional logic, simple Deduction Frege systems, general Deduction Frege systems and nested Deduction Frege systems, which augment Frege systems with variants of the Deduction Rule. We give upper bounds on the lengths of proofs in Frege proof systems compared to lengths in these new systems. As applications we give near-linear simulations of the propositional Gentzen sequent calculus and the natural Deduction calculus by Frege proofs. The length of a proof is the number of lines (or formulas) in the proof. A general Deduction Frege proof system provides at most quadratic speedup over Frege proof systems. A nested Deduction Frege proof system provides at most a nearly linear speedup over Frege system where by “nearly linear” is meant the ratio of proof lengths is O(α(n)) where α is the inverse Ackermann function. A nested Deduction Frege system can linearly simulate the propositional sequent calculus, the tree-like general Deduction Frege calculus, and the natural Deduction calculus. Hence a Frege proof system can simulate all those proof systems with proof lengths bounded by O(n · α(n)). Also we show Supported in part by NSF Grant DMS-8902480. 1 that a Frege proof of n lines can be transformed into a tree-like Frege proof of O(n log n) lines and of height O(log n). As a corollary of this fact we can prove that natural Deduction and sequent calculus tree-like systems simulate Frege systems with proof lengths bounded by O(n log n).
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on the Deduction Rule and the number of proof lines
Logic in Computer Science, 1991Co-Authors: Maria Luisa Bonet, Samuel R BussAbstract:Proof systems for propositional logic called simple Deduction Frege systems, general Deduction Frege systems, and nested Deduction Frege systems, which augment Frege systems with variants of the Deduction Rule, are introduced. Upper bounds are given on the lengths of proofs in these systems compared to lengths in Frege proof systems. As an application, a near-linear simulation of the propositional Gentzen sequent calculus by Frege proofs is presented. It is shown that a general Deduction Frege proof system provides at most quadratic speedup over Frege proof systems. A nested Deduction Frege proof system provides at most quadratic speedup over Frege proof systems. A nested Deduction Frege proof system provides at most a nearly linear speedup over Frege systems where by 'nearly linear' is meant that the ratio of proof lengths is O( alpha (n)), where alpha is the inverse Ackermann function. A nested Deduction Frege system can linearly simulate the propositional sequent calculus, and hence a Frege proof system can simulate the propositional sequent calculus with proof lengths bounded by O(n alpha (n)). As a technical tool, the serial transitive closure problem is introduced. Given a directed graph and a list of closure edges in the transitive closure of the graph, the problem is to derive all the closure edges. A nearly linear bound is given on the number of steps in such a derivation when the graph is treelike. >
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LICS - On the Deduction Rule and the number of proof lines
[1991] Proceedings Sixth Annual IEEE Symposium on Logic in Computer Science, 1Co-Authors: Maria Luisa Bonet, Samuel R BussAbstract:Proof systems for propositional logic called simple Deduction Frege systems, general Deduction Frege systems, and nested Deduction Frege systems, which augment Frege systems with variants of the Deduction Rule, are introduced. Upper bounds are given on the lengths of proofs in these systems compared to lengths in Frege proof systems. As an application, a near-linear simulation of the propositional Gentzen sequent calculus by Frege proofs is presented. It is shown that a general Deduction Frege proof system provides at most quadratic speedup over Frege proof systems. A nested Deduction Frege proof system provides at most quadratic speedup over Frege proof systems. A nested Deduction Frege proof system provides at most a nearly linear speedup over Frege systems where by 'nearly linear' is meant that the ratio of proof lengths is O( alpha (n)), where alpha is the inverse Ackermann function. A nested Deduction Frege system can linearly simulate the propositional sequent calculus, and hence a Frege proof system can simulate the propositional sequent calculus with proof lengths bounded by O(n alpha (n)). As a technical tool, the serial transitive closure problem is introduced. Given a directed graph and a list of closure edges in the transitive closure of the graph, the problem is to derive all the closure edges. A nearly linear bound is given on the number of steps in such a derivation when the graph is treelike. >
Maria Luisa Bonet - One of the best experts on this subject based on the ideXlab platform.
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The Deduction Rule and linear and near-linear proof simulations
Journal of Symbolic Logic, 1993Co-Authors: Maria Luisa Bonet, Samuel R BussAbstract:We introduce new proof systems for propositional logic, simple Deduction Frege systems, general Deduction Frege systems and nested Deduction Frege systems, which augment Frege systems with variants of the Deduction Rule. We give upper bounds on the lengths of proofs in Frege proof systems compared to lengths in these new systems. As applications we give near-linear simulations of the propositional Gentzen sequent calculus and the natural Deduction calculus by Frege proofs. The length of a proof is the number of lines (or formulas) in the proof. A general Deduction Frege proof system provides at most quadratic speedup over Frege proof systems. A nested Deduction Frege proof system provides at most a nearly linear speedup over Frege system where by “nearly linear” is meant the ratio of proof lengths is O(α(n)) where α is the inverse Ackermann function. A nested Deduction Frege system can linearly simulate the propositional sequent calculus, the tree-like general Deduction Frege calculus, and the natural Deduction calculus. Hence a Frege proof system can simulate all those proof systems with proof lengths bounded by O(n · α(n)). Also we show Supported in part by NSF Grant DMS-8902480. 1 that a Frege proof of n lines can be transformed into a tree-like Frege proof of O(n log n) lines and of height O(log n). As a corollary of this fact we can prove that natural Deduction and sequent calculus tree-like systems simulate Frege systems with proof lengths bounded by O(n log n).
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on the Deduction Rule and the number of proof lines
Logic in Computer Science, 1991Co-Authors: Maria Luisa Bonet, Samuel R BussAbstract:Proof systems for propositional logic called simple Deduction Frege systems, general Deduction Frege systems, and nested Deduction Frege systems, which augment Frege systems with variants of the Deduction Rule, are introduced. Upper bounds are given on the lengths of proofs in these systems compared to lengths in Frege proof systems. As an application, a near-linear simulation of the propositional Gentzen sequent calculus by Frege proofs is presented. It is shown that a general Deduction Frege proof system provides at most quadratic speedup over Frege proof systems. A nested Deduction Frege proof system provides at most quadratic speedup over Frege proof systems. A nested Deduction Frege proof system provides at most a nearly linear speedup over Frege systems where by 'nearly linear' is meant that the ratio of proof lengths is O( alpha (n)), where alpha is the inverse Ackermann function. A nested Deduction Frege system can linearly simulate the propositional sequent calculus, and hence a Frege proof system can simulate the propositional sequent calculus with proof lengths bounded by O(n alpha (n)). As a technical tool, the serial transitive closure problem is introduced. Given a directed graph and a list of closure edges in the transitive closure of the graph, the problem is to derive all the closure edges. A nearly linear bound is given on the number of steps in such a derivation when the graph is treelike. >
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LICS - On the Deduction Rule and the number of proof lines
[1991] Proceedings Sixth Annual IEEE Symposium on Logic in Computer Science, 1Co-Authors: Maria Luisa Bonet, Samuel R BussAbstract:Proof systems for propositional logic called simple Deduction Frege systems, general Deduction Frege systems, and nested Deduction Frege systems, which augment Frege systems with variants of the Deduction Rule, are introduced. Upper bounds are given on the lengths of proofs in these systems compared to lengths in Frege proof systems. As an application, a near-linear simulation of the propositional Gentzen sequent calculus by Frege proofs is presented. It is shown that a general Deduction Frege proof system provides at most quadratic speedup over Frege proof systems. A nested Deduction Frege proof system provides at most quadratic speedup over Frege proof systems. A nested Deduction Frege proof system provides at most a nearly linear speedup over Frege systems where by 'nearly linear' is meant that the ratio of proof lengths is O( alpha (n)), where alpha is the inverse Ackermann function. A nested Deduction Frege system can linearly simulate the propositional sequent calculus, and hence a Frege proof system can simulate the propositional sequent calculus with proof lengths bounded by O(n alpha (n)). As a technical tool, the serial transitive closure problem is introduced. Given a directed graph and a list of closure edges in the transitive closure of the graph, the problem is to derive all the closure edges. A nearly linear bound is given on the number of steps in such a derivation when the graph is treelike. >
Manoj Viswanathan - One of the best experts on this subject based on the ideXlab platform.
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Caveat IRS: Problems with Abandoning the Full Deduction Rule
2018Co-Authors: David Gamage, Joseph Bankman, Jacob Goldin, Daniel Jacob Hemel, Darien Shanske, Kirk J. Stark, Dennis J. Ventry, Manoj ViswanathanAbstract:Author(s): Bankman, Joseph; Gamage, David; Goldin, Jacob; Hemel, Daniel Jacob; Shanske, Darien; Stark, Kirk J; Ventry, Dennis J; Viswanathan, Manoj
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Caveat IRS: Problems with Abandoning the Full Deduction Rule
2018Co-Authors: Joseph Bankman, David Gamage, Jacob Goldin, Daniel Jacob Hemel, Darien Shanske, Kirk J. Stark, Dennis J. Ventry, Manoj ViswanathanAbstract:Several states have passed — and many more are considering — new tax credits that would reduce tax liability based on donations made by a taxpayer in support of various state, local or non-profit programs. In general, taxpayer contributions to qualifying organizations — including public charities and private foundations, as well as federal, state, local, and tribal governments — are eligible for the federal charitable contribution Deduction under section 170. In a previous article, we explained how current law supports the view that qualifying charitable contributions are deductible under section 170, even when the donor derives some federal or state tax benefit by making the donation. We referred to this treatment as the “full Deduction Rule.” Some commentators have suggested that Treasury and the IRS could change existing law, whether through new regulations or by issuing a new interpretation of existing regulations, to limit the deductibility of taxpayer contributions when they trigger a state or local tax benefit to the donor. Many legal and administrative concerns are associated with those actions. In this report, we argue that even if the IRS has the legal authority to implement the changes absent new legislation, it should decline to do so.
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State Responses to Federal Tax Reform: Charitable Tax Credits
SSRN Electronic Journal, 2018Co-Authors: Joseph Bankman, David Gamage, Jacob Goldin, Daniel Jacob Hemel, Darien Shanske, Kirk J. Stark, Dennis J. Ventry, Manoj ViswanathanAbstract:This paper summarizes the current federal income tax treatment of charitable contributions where the gift entitles the donor to a state tax credit. Such credits are very common and are used by the states to encourage private donations to a wide range of activities, including natural resource preservation through conservation easements, private school tuition scholarship programs, financial aid for college-bound children from low-income households, shelters for victims of domestic violence, and numerous other state-supported programs. Under these programs, taxpayers receive tax credits for donations to governments, government-created funds, and nonprofits. A central federal income tax question raised by these donations is whether the donor must reduce the amount of the charitable contribution Deduction claimed on her federal income tax return by the value of state tax benefits generated by the gift. Under current law, expressed through both court opinions and rulings from the Internal Revenue Service, the amount of the donor’s charitable contribution Deduction is not reduced by the value of state tax benefits. The effect of this "Full Deduction Rule" is that a taxpayer can reduce her state tax liability by making a charitable contribution that is deductible on her federal income tax return. In a tax system where both charitable contributions and state/local taxes are deductible, the ability to reduce state tax liabilities via charitable contributions confers no particular federal tax advantage. However, in a tax system where charitable contributions are deductible but state/local taxes are not, it may be possible for states to provide their residents a means of preserving the effects of a state/local tax Deduction, at least in part, by granting a charitable tax credit for federally deductible gifts, including gifts to the state or one of its political subdivisions. In light of recent federal legislation further limiting the deductibility of state and local taxes, states may expand their use of charitable tax credits in this manner, focusing new attention on the legal underpinnings of the Full Deduction Rule. The Full Deduction Rule has been applied to credits that completely offset the pre-tax cost of the contribution. In most cases, however, the state credits offset less than 100% of the cost. We believe that, at least in this latter and more typical set of cases, the Full Deduction Rule represents a correct and long-standing trans-substantive principle of federal tax law. According to judicial and administrative pronouncements issued over several decades, nonrefundable state tax credits are treated as a reduction or potential reduction of the credit recipient’s state tax liability rather than as a receipt of money, property, contribution to capital, or other item of gross income. The Full Deduction Rule is also supported by a host of policy considerations, including federal respect for state initiatives and allocation of tax liabilities, and near-insuperable administrative burdens posed by alternative Rules. It is possible to devise alternatives to the Full Deduction Rule that would require donors to reduce the amount of their charitable contribution Deductions by some or all of the federal, state, or local tax benefits generated by making a gift. Whether those alternatives could be accomplished administratively or would require legislation depends on the details of any such proposal. We believe that Congress is best situated to balance the many competing interests that changes to current law would necessarily implicate. We also caution Congress that a legislative override of the Full Deduction Rule would raise significant administrability concerns and would implicate important federalism values. Congress should tread carefully if it seeks to alter the Full Deduction Rule by statute.
Joseph Bankman - One of the best experts on this subject based on the ideXlab platform.
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Caveat IRS: Problems with Abandoning the Full Deduction Rule
2018Co-Authors: David Gamage, Joseph Bankman, Jacob Goldin, Daniel Jacob Hemel, Darien Shanske, Kirk J. Stark, Dennis J. Ventry, Manoj ViswanathanAbstract:Author(s): Bankman, Joseph; Gamage, David; Goldin, Jacob; Hemel, Daniel Jacob; Shanske, Darien; Stark, Kirk J; Ventry, Dennis J; Viswanathan, Manoj
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Caveat IRS: Problems with Abandoning the Full Deduction Rule
2018Co-Authors: Joseph Bankman, David Gamage, Jacob Goldin, Daniel Jacob Hemel, Darien Shanske, Kirk J. Stark, Dennis J. Ventry, Manoj ViswanathanAbstract:Several states have passed — and many more are considering — new tax credits that would reduce tax liability based on donations made by a taxpayer in support of various state, local or non-profit programs. In general, taxpayer contributions to qualifying organizations — including public charities and private foundations, as well as federal, state, local, and tribal governments — are eligible for the federal charitable contribution Deduction under section 170. In a previous article, we explained how current law supports the view that qualifying charitable contributions are deductible under section 170, even when the donor derives some federal or state tax benefit by making the donation. We referred to this treatment as the “full Deduction Rule.” Some commentators have suggested that Treasury and the IRS could change existing law, whether through new regulations or by issuing a new interpretation of existing regulations, to limit the deductibility of taxpayer contributions when they trigger a state or local tax benefit to the donor. Many legal and administrative concerns are associated with those actions. In this report, we argue that even if the IRS has the legal authority to implement the changes absent new legislation, it should decline to do so.
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State Responses to Federal Tax Reform: Charitable Tax Credits
SSRN Electronic Journal, 2018Co-Authors: Joseph Bankman, David Gamage, Jacob Goldin, Daniel Jacob Hemel, Darien Shanske, Kirk J. Stark, Dennis J. Ventry, Manoj ViswanathanAbstract:This paper summarizes the current federal income tax treatment of charitable contributions where the gift entitles the donor to a state tax credit. Such credits are very common and are used by the states to encourage private donations to a wide range of activities, including natural resource preservation through conservation easements, private school tuition scholarship programs, financial aid for college-bound children from low-income households, shelters for victims of domestic violence, and numerous other state-supported programs. Under these programs, taxpayers receive tax credits for donations to governments, government-created funds, and nonprofits. A central federal income tax question raised by these donations is whether the donor must reduce the amount of the charitable contribution Deduction claimed on her federal income tax return by the value of state tax benefits generated by the gift. Under current law, expressed through both court opinions and rulings from the Internal Revenue Service, the amount of the donor’s charitable contribution Deduction is not reduced by the value of state tax benefits. The effect of this "Full Deduction Rule" is that a taxpayer can reduce her state tax liability by making a charitable contribution that is deductible on her federal income tax return. In a tax system where both charitable contributions and state/local taxes are deductible, the ability to reduce state tax liabilities via charitable contributions confers no particular federal tax advantage. However, in a tax system where charitable contributions are deductible but state/local taxes are not, it may be possible for states to provide their residents a means of preserving the effects of a state/local tax Deduction, at least in part, by granting a charitable tax credit for federally deductible gifts, including gifts to the state or one of its political subdivisions. In light of recent federal legislation further limiting the deductibility of state and local taxes, states may expand their use of charitable tax credits in this manner, focusing new attention on the legal underpinnings of the Full Deduction Rule. The Full Deduction Rule has been applied to credits that completely offset the pre-tax cost of the contribution. In most cases, however, the state credits offset less than 100% of the cost. We believe that, at least in this latter and more typical set of cases, the Full Deduction Rule represents a correct and long-standing trans-substantive principle of federal tax law. According to judicial and administrative pronouncements issued over several decades, nonrefundable state tax credits are treated as a reduction or potential reduction of the credit recipient’s state tax liability rather than as a receipt of money, property, contribution to capital, or other item of gross income. The Full Deduction Rule is also supported by a host of policy considerations, including federal respect for state initiatives and allocation of tax liabilities, and near-insuperable administrative burdens posed by alternative Rules. It is possible to devise alternatives to the Full Deduction Rule that would require donors to reduce the amount of their charitable contribution Deductions by some or all of the federal, state, or local tax benefits generated by making a gift. Whether those alternatives could be accomplished administratively or would require legislation depends on the details of any such proposal. We believe that Congress is best situated to balance the many competing interests that changes to current law would necessarily implicate. We also caution Congress that a legislative override of the Full Deduction Rule would raise significant administrability concerns and would implicate important federalism values. Congress should tread carefully if it seeks to alter the Full Deduction Rule by statute.
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The Full Deduction Rule and the Substance Over Form Doctrine
SSRN Electronic Journal, 2018Co-Authors: Joseph Bankman, Darien ShanskeAbstract:In this essay, we discuss the application of substance over form and related common-law interpretive doctrines to the new donation credit proposals, the so-called “SALT workarounds.” The authors conclude that, unlike in the context of corporate tax shelters, application of these doctrines would involve the IRS and courts in decisions best left for Congress. This is not only because applying these doctrines will require making intrusive and controversial policy decisions, but also because there is no rush. The classic tax shelters were developed in secret and often took years to come to the attention of the IRS, and still longer before legislation could prospectively reduce their benefits. Promoters could be three shelters down the road before an earlier one was uncovered. If shelters worked until they were legislated against, there would always be shelters that worked, and new shelters in development. Application of backup common law doctrines was, as a practical matter, a necessity. That is not the case here; Congress is clearly aware of the issue and can make distinctions between different programs and beneficiaries as it sees fit. Authors’ Note: This Essay was written before the promulgation of regulations in connection with state responses to the capping of the SALT Deduction.
