The Experts below are selected from a list of 51396 Experts worldwide ranked by ideXlab platform
Rouzbeh Hasheminezhad - One of the best experts on this subject based on the ideXlab platform.
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algorithmic analysis of qualitative and quantitative termination problems for affine probabilistic programs
ACM Transactions on Programming Languages and Systems, 2018Co-Authors: Krishnendu Chatterjee, Petr Novotný, Rouzbeh HasheminezhadAbstract:In this article, we consider the termination problem of probabilistic programs with real-valued variables. The questions concerned are: qualitative ones that ask (i) whether the program terminates with probability 1 (almost-sure termination) and (ii) whether the expected termination time is finite (finite termination); and quantitative ones that ask (i) to approximate the expected termination time (expectation problem) and (ii) to compute a bound B such that the probability not to terminate after B steps decreases exponentially (concentration problem). To solve these questions, we utilize the notion of ranking supermartingales, which is a powerful approach for proving termination of probabilistic programs. In detail, we focus on algorithmic synthesis of linear ranking-supermartingales over affine probabilistic programs (Apps) with both angelic and demonic non-Determinism. An important subclass of Apps is LRApp which is defined as the class of all Apps over which a linear ranking-supermartingale exists. Our main contributions are as follows. Firstly, we show that the membership problem of LRApp (i) can be decided in polynomial time for Apps with at most demonic non-Determinism, and (ii) is NP-hard and in PSPACE for Apps with angelic non-Determinism. Moreover, the NP-hardness result holds already for Apps without probability and demonic non-Determinism. Secondly, we show that the concentration problem over LRApp can be solved in the same complexity as for the membership problem of LRApp. Finally, we show that the expectation problem over LRApp can be solved in 2EXPTIME and is PSPACE-hard even for Apps without probability and non-Determinism (i.e., deterministic programs). Our experimental results demonstrate the effectiveness of our approach to answer the qualitative and quantitative questions over Apps with at most demonic non-Determinism.
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algorithmic analysis of qualitative and quantitative termination problems for affine probabilistic programs
Symposium on Principles of Programming Languages, 2016Co-Authors: Krishnendu Chatterjee, Petr Novotný, Rouzbeh HasheminezhadAbstract:In this paper, we consider termination of probabilistic programs with real-valued variables. The questions concerned are: 1. qualitative ones that ask (i) whether the program terminates with probability 1 (almost-sure termination) and (ii) whether the expected termination time is finite (finite termination); 2. quantitative ones that ask (i) to approximate the expected termination time (expectation problem) and (ii) to compute a bound B such that the probability to terminate after B steps decreases exponentially (concentration problem). To solve these questions, we utilize the notion of ranking supermartingales which is a powerful approach for proving termination of probabilistic programs. In detail, we focus on algorithmic synthesis of linear ranking-supermartingales over affine probabilistic programs (APP's) with both angelic and demonic non-Determinism. An important subclass of APP's is LRAPP which is defined as the class of all APP's over which a linear ranking-supermartingale exists. Our main contributions are as follows. Firstly, we show that the membership problem of LRAPP (i) can be decided in polynomial time for APP's with at most demonic non-Determinism, and (ii) is NP-hard and in PSPACE for APP's with angelic non-Determinism; moreover, the NP-hardness result holds already for APP's without probability and demonic non-Determinism. Secondly, we show that the concentration problem over LRAPP can be solved in the same complexity as for the membership problem of LRAPP. Finally, we show that the expectation problem over LRAPP can be solved in 2EXPTIME and is PSPACE-hard even for APP's without probability and non-Determinism (i.e., deterministic programs). Our experimental results demonstrate the effectiveness of our approach to answer the qualitative and quantitative questions over APP's with at most demonic non-Determinism.
Gernot Von Collani - One of the best experts on this subject based on the ideXlab platform.
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hindsight bias doesn t always come easy causal models cognitive effort and creeping Determinism
Journal of Experimental Psychology: Learning Memory and Cognition, 2008Co-Authors: Steffen Nestler, Hartmut Blank, Gernot Von CollaniAbstract:Creeping Determinism, a form of hindsight bias, refers to people's hindsight perceptions of events as being determined or inevitable. This article proposes, on the basis of a causal-model theory of creeping Determinism, that the underlying processes are effortful, and hence creeping Determinism should disappear when individuals lack the cognitive resources to make sense of an outcome. In Experiments 1 and 2, participants were asked to read a scenario while they were under either low or high processing load. Participants who had the cognitive resources to make sense of the outcome perceived it as more probable and necessary than did participants under high processing load or participants who did not receive outcome information. Experiment 3 was designed to separate 2 postulated subprocesses and showed that the attenuating effect of processing load on hindsight bias is not due to a disruption of the retrieval of potential causal antecedents but to a disruption of their evaluation. Together the 3 experiments show that the processes underlying creeping Determinism are effortful, and they highlight the crucial role of causal reasoning in the perception of past events.
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hindsight bias and causal attribution a causal model theory of creeping Determinism
Social Psychology, 2008Co-Authors: Steffen Nestler, Hartmut Blank, Gernot Von CollaniAbstract:Hindsight bias describes characteristic changes in the perceptions of events or facts once their outcomes are known. This article focuses on one important facet of this, named creeping Determinism, denoting enhanced hindsight perceptions of the inevitability of event outcomes. We suggest a systematic link between the literatures on causal attribution and hindsight bias/creeping Determinism and introduce a comprehensive causal model theory (CMT) of creeping Determinism. We then distinguish between two alternative versions of CMT, which reflect recent debates in the causal attribution literature. These versions assume, respectively, that individuals make causal attributions by means of covariation analysis or via the discovery of some underlying mechanism. In order to contrast these assumptions, we introduce a new hypothesis concerning the magnitude of creeping Determinism, based on the conjunction effect in causal attribution, and we present empirical evidence concerning this hypothesis.
Roy F Baumeister - One of the best experts on this subject based on the ideXlab platform.
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forget the folk moral responsibility preservation motives and other conditions for compatibilism
Frontiers in Psychology, 2019Co-Authors: Cory J Clark, Bo Winegard, Roy F BaumeisterAbstract:For years, experimental philosophers have attempted to discern whether laypeople find free will compatible with a scientifically deterministic understanding of the universe, yet no consensus has emerged. The present work provides one potential explanation for these discrepant findings: People are strongly motivated to preserve free will and moral responsibility, and thus do not have stable, logically rigorous notions of free will. Seven studies support this hypothesis by demonstrating that a variety of logically irrelevant (but motivationally relevant) features influence compatibilist judgments. In Study 1, participants who were asked to consider the possibility that our universe is deterministic were more compatibilist than those not asked to consider this possibility, suggesting that Determinism poses a threat to moral responsibility, which increases compatibilist responding (thus reducing the threat). In Study 2, participants who considered concrete instances of moral behavior found compatibilist free will more sufficient for moral responsibility than participants who were asked about moral responsibility more generally. In Study 3a, the order in which participants read free will and Determinism descriptions influenced their compatibilist judgments-and only when the descriptions had moral significance: Participants were more likely to report that Determinism was compatible with free will than that free will was compatible with Determinism. In Study 3b, participants who read the free will description first (the more compatibilist group) were particularly likely to confess that their beliefs in free will and moral responsibility and their disbelief in Determinism influenced their conclusion. In Study 4, participants reduced their compatibilist beliefs after reading a passage that argued that moral responsibility could be preserved even in the absence of free will. Participants also reported that immaterial souls were compatible with scientific Determinism, most strongly among immaterial soul believers (Study 5), and evaluated information about the capacities of primates in a biased manner favoring the existence of human free will (Study 6). These results suggest that people do not have one intuition about whether free will is compatible with Determinism. Instead, people report that free will is compatible with Determinism when desiring to uphold moral responsibility. Recommendations for future work are discussed.
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Data_Sheet_2_Forget the Folk: Moral Responsibility Preservation Motives and Other Conditions for Compatibilism.PDF
2019Co-Authors: Cory J Clark, Bo Winegard, Roy F BaumeisterAbstract:For years, experimental philosophers have attempted to discern whether laypeople find free will compatible with a scientifically deterministic understanding of the universe, yet no consensus has emerged. The present work provides one potential explanation for these discrepant findings: People are strongly motivated to preserve free will and moral responsibility, and thus do not have stable, logically rigorous notions of free will. Seven studies support this hypothesis by demonstrating that a variety of logically irrelevant (but motivationally relevant) features influence compatibilist judgments. In Study 1, participants who were asked to consider the possibility that our universe is deterministic were more compatibilist than those not asked to consider this possibility, suggesting that Determinism poses a threat to moral responsibility, which increases compatibilist responding (thus reducing the threat). In Study 2, participants who considered concrete instances of moral behavior found compatibilist free will more sufficient for moral responsibility than participants who were asked about moral responsibility more generally. In Study 3a, the order in which participants read free will and Determinism descriptions influenced their compatibilist judgments–and only when the descriptions had moral significance: Participants were more likely to report that Determinism was compatible with free will than that free will was compatible with Determinism. In Study 3b, participants who read the free will description first (the more compatibilist group) were particularly likely to confess that their beliefs in free will and moral responsibility and their disbelief in Determinism influenced their conclusion. In Study 4, participants reduced their compatibilist beliefs after reading a passage that argued that moral responsibility could be preserved even in the absence of free will. Participants also reported that immaterial souls were compatible with scientific Determinism, most strongly among immaterial soul believers (Study 5), and evaluated information about the capacities of primates in a biased manner favoring the existence of human free will (Study 6). These results suggest that people do not have one intuition about whether free will is compatible with Determinism. Instead, people report that free will is compatible with Determinism when desiring to uphold moral responsibility. Recommendations for future work are discussed.
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Data_Sheet_1_Forget the Folk: Moral Responsibility Preservation Motives and Other Conditions for Compatibilism.ZIP
2019Co-Authors: Cory J Clark, Bo Winegard, Roy F BaumeisterAbstract:For years, experimental philosophers have attempted to discern whether laypeople find free will compatible with a scientifically deterministic understanding of the universe, yet no consensus has emerged. The present work provides one potential explanation for these discrepant findings: People are strongly motivated to preserve free will and moral responsibility, and thus do not have stable, logically rigorous notions of free will. Seven studies support this hypothesis by demonstrating that a variety of logically irrelevant (but motivationally relevant) features influence compatibilist judgments. In Study 1, participants who were asked to consider the possibility that our universe is deterministic were more compatibilist than those not asked to consider this possibility, suggesting that Determinism poses a threat to moral responsibility, which increases compatibilist responding (thus reducing the threat). In Study 2, participants who considered concrete instances of moral behavior found compatibilist free will more sufficient for moral responsibility than participants who were asked about moral responsibility more generally. In Study 3a, the order in which participants read free will and Determinism descriptions influenced their compatibilist judgments–and only when the descriptions had moral significance: Participants were more likely to report that Determinism was compatible with free will than that free will was compatible with Determinism. In Study 3b, participants who read the free will description first (the more compatibilist group) were particularly likely to confess that their beliefs in free will and moral responsibility and their disbelief in Determinism influenced their conclusion. In Study 4, participants reduced their compatibilist beliefs after reading a passage that argued that moral responsibility could be preserved even in the absence of free will. Participants also reported that immaterial souls were compatible with scientific Determinism, most strongly among immaterial soul believers (Study 5), and evaluated information about the capacities of primates in a biased manner favoring the existence of human free will (Study 6). These results suggest that people do not have one intuition about whether free will is compatible with Determinism. Instead, people report that free will is compatible with Determinism when desiring to uphold moral responsibility. Recommendations for future work are discussed.
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forget the folk moral responsibility preservation motives and other conditions for compatibilism
Social Science Research Network, 2017Co-Authors: Cory J Clark, Bo Winegard, Roy F BaumeisterAbstract:For years, experimental philosophers have attempted to discern whether laypeople find free will compatible with a scientifically deterministic understanding of the universe. We argue that these attempts are misguided because (1) lay people do not have stable, logically rigorous notions of free will and (2) people are strongly motivated to preserve free will and moral responsibility. Seven studies support this hypothesis by demonstrating that a variety of logically irrelevant (but motivationally relevant) features influence compatibilist judgments. In Study 1, participants who were asked to consider the possibility that our universe is deterministic were more compatibilist than those not asked to consider this possibility, suggesting that compatibilism is particularly compelling when Determinism poses potential threats to moral responsibility. In Study 2, participants who considered concrete instances of moral behavior found compatibilist free will more sufficient for moral responsibility than participants who were asked about moral responsibility more generally. In Study 3a, the order in which participants read free will and Determinism arguments influenced their compatibilist judgments—and only when the arguments had moral significance: Participants were more likely to report that Determinism was compatible with free will than that free will was compatible with Determinism. In Study 3b, participants who read the free will argument first (the more compatibilist group) were particularly likely to confess that their beliefs in free will and moral responsibility and their disbelief in Determinism influenced their conclusion. In Study 4, participants reduced their compatibilist beliefs after reading a passage that argued that moral responsibility can be preserved even in the absence of free will. Participants also reported that immaterial souls were compatible with scientific Determinism, most strongly among immaterial soul believers (Study 5), and evaluated information about the capacities of primates in a biased manner favoring the existence of human free will (Study 6). These results suggest that people do not have one intuition about whether free will is compatible with Determinism. Rather, people report that free will is compatible with Determinism when desiring to uphold moral responsibility. Recommendations for future work are discussed.
Krishnendu Chatterjee - One of the best experts on this subject based on the ideXlab platform.
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algorithmic analysis of qualitative and quantitative termination problems for affine probabilistic programs
ACM Transactions on Programming Languages and Systems, 2018Co-Authors: Krishnendu Chatterjee, Petr Novotný, Rouzbeh HasheminezhadAbstract:In this article, we consider the termination problem of probabilistic programs with real-valued variables. The questions concerned are: qualitative ones that ask (i) whether the program terminates with probability 1 (almost-sure termination) and (ii) whether the expected termination time is finite (finite termination); and quantitative ones that ask (i) to approximate the expected termination time (expectation problem) and (ii) to compute a bound B such that the probability not to terminate after B steps decreases exponentially (concentration problem). To solve these questions, we utilize the notion of ranking supermartingales, which is a powerful approach for proving termination of probabilistic programs. In detail, we focus on algorithmic synthesis of linear ranking-supermartingales over affine probabilistic programs (Apps) with both angelic and demonic non-Determinism. An important subclass of Apps is LRApp which is defined as the class of all Apps over which a linear ranking-supermartingale exists. Our main contributions are as follows. Firstly, we show that the membership problem of LRApp (i) can be decided in polynomial time for Apps with at most demonic non-Determinism, and (ii) is NP-hard and in PSPACE for Apps with angelic non-Determinism. Moreover, the NP-hardness result holds already for Apps without probability and demonic non-Determinism. Secondly, we show that the concentration problem over LRApp can be solved in the same complexity as for the membership problem of LRApp. Finally, we show that the expectation problem over LRApp can be solved in 2EXPTIME and is PSPACE-hard even for Apps without probability and non-Determinism (i.e., deterministic programs). Our experimental results demonstrate the effectiveness of our approach to answer the qualitative and quantitative questions over Apps with at most demonic non-Determinism.
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algorithmic analysis of qualitative and quantitative termination problems for affine probabilistic programs
Symposium on Principles of Programming Languages, 2016Co-Authors: Krishnendu Chatterjee, Petr Novotný, Rouzbeh HasheminezhadAbstract:In this paper, we consider termination of probabilistic programs with real-valued variables. The questions concerned are: 1. qualitative ones that ask (i) whether the program terminates with probability 1 (almost-sure termination) and (ii) whether the expected termination time is finite (finite termination); 2. quantitative ones that ask (i) to approximate the expected termination time (expectation problem) and (ii) to compute a bound B such that the probability to terminate after B steps decreases exponentially (concentration problem). To solve these questions, we utilize the notion of ranking supermartingales which is a powerful approach for proving termination of probabilistic programs. In detail, we focus on algorithmic synthesis of linear ranking-supermartingales over affine probabilistic programs (APP's) with both angelic and demonic non-Determinism. An important subclass of APP's is LRAPP which is defined as the class of all APP's over which a linear ranking-supermartingale exists. Our main contributions are as follows. Firstly, we show that the membership problem of LRAPP (i) can be decided in polynomial time for APP's with at most demonic non-Determinism, and (ii) is NP-hard and in PSPACE for APP's with angelic non-Determinism; moreover, the NP-hardness result holds already for APP's without probability and demonic non-Determinism. Secondly, we show that the concentration problem over LRAPP can be solved in the same complexity as for the membership problem of LRAPP. Finally, we show that the expectation problem over LRAPP can be solved in 2EXPTIME and is PSPACE-hard even for APP's without probability and non-Determinism (i.e., deterministic programs). Our experimental results demonstrate the effectiveness of our approach to answer the qualitative and quantitative questions over APP's with at most demonic non-Determinism.
Steffen Nestler - One of the best experts on this subject based on the ideXlab platform.
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hindsight bias doesn t always come easy causal models cognitive effort and creeping Determinism
Journal of Experimental Psychology: Learning Memory and Cognition, 2008Co-Authors: Steffen Nestler, Hartmut Blank, Gernot Von CollaniAbstract:Creeping Determinism, a form of hindsight bias, refers to people's hindsight perceptions of events as being determined or inevitable. This article proposes, on the basis of a causal-model theory of creeping Determinism, that the underlying processes are effortful, and hence creeping Determinism should disappear when individuals lack the cognitive resources to make sense of an outcome. In Experiments 1 and 2, participants were asked to read a scenario while they were under either low or high processing load. Participants who had the cognitive resources to make sense of the outcome perceived it as more probable and necessary than did participants under high processing load or participants who did not receive outcome information. Experiment 3 was designed to separate 2 postulated subprocesses and showed that the attenuating effect of processing load on hindsight bias is not due to a disruption of the retrieval of potential causal antecedents but to a disruption of their evaluation. Together the 3 experiments show that the processes underlying creeping Determinism are effortful, and they highlight the crucial role of causal reasoning in the perception of past events.
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hindsight bias and causal attribution a causal model theory of creeping Determinism
Social Psychology, 2008Co-Authors: Steffen Nestler, Hartmut Blank, Gernot Von CollaniAbstract:Hindsight bias describes characteristic changes in the perceptions of events or facts once their outcomes are known. This article focuses on one important facet of this, named creeping Determinism, denoting enhanced hindsight perceptions of the inevitability of event outcomes. We suggest a systematic link between the literatures on causal attribution and hindsight bias/creeping Determinism and introduce a comprehensive causal model theory (CMT) of creeping Determinism. We then distinguish between two alternative versions of CMT, which reflect recent debates in the causal attribution literature. These versions assume, respectively, that individuals make causal attributions by means of covariation analysis or via the discovery of some underlying mechanism. In order to contrast these assumptions, we introduce a new hypothesis concerning the magnitude of creeping Determinism, based on the conjunction effect in causal attribution, and we present empirical evidence concerning this hypothesis.
