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Anant Sahai - One of the best experts on this subject based on the ideXlab platform.
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Control Capacity
IEEE Transactions on Information Theory, 2019Co-Authors: Gireeja Ranade, Anant SahaiAbstract:Feedback Control actively dissipates uncertainty from a dynamical system by means of actuation. We develop a notion of “Control Capacity” that gives a fundamental limit (in bits) on the rate at which a Controller can dissipate the uncertainty from a system, i.e., stabilize to a known fixed point. We give a computable single-letter characterization of Control Capacity for memoryless stationary scalar multiplicative actuation channels. Control Capacity allows us to answer questions of stabilizability for scalar linear systems: a system with actuation uncertainty is stabilizable if and only if the Control Capacity is larger than the log of the unstable open-loop eigenvalue. For second-moment senses of stability, we recover the classic uncertainty threshold principle result. However, our definition of Control Capacity can quantify the stabilizability limits for any moment of stability. Our formulation parallels the notion of Shannon’s communication Capacity and thus yields both a strong converse and a way to compute the value of side information in Control.
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Control Capacity
2017Co-Authors: Gireeja Ranade, Anant SahaiAbstract:Feedback Control actively dissipates uncertainty from a dynamical system by means of actuation. We develop a notion of "Control Capacity" that gives a fundamental limit (in bits) on the rate at which a Controller can dissipate the uncertainty from a system, i.e. stabilize to a known fixed point. We give a computable single-letter characterization of Control Capacity for memoryless stationary scalar multiplicative actuation channels. Control Capacity allows us to answer questions of stabilizability for scalar linear systems: a system with actuation uncertainty is stabilizable if and only if the Control Capacity is larger than the log of the unstable open-loop eigenvalue. For second-moment senses of stability, we recover the classic uncertainty threshold principle result. However, our definition of Control Capacity can quantify the stabilizability limits for any moment of stability. Our formulation parallels the notion of Shannon's communication Capacity, and thus yields both a strong converse and a way to compute the value of side-information in Control. The results in our paper are motivated by bit-level models for Control that build on the deterministic models that are widely used to understand information flows in wireless network information theory.
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Control Capacity
2015 IEEE International Symposium on Information Theory (ISIT), 2015Co-Authors: Gireeja Ranade, Anant SahaiAbstract:This paper presents a notion of “Control Capacity” that gives a fundamental limit on the Control of a system through an unreliable actuation channel. It tells us how fast we can reliably actively dissipate uncertainty in a system through that actuation channel. We give a computable single-letter characterization for scalar systems with memoryless stationary multiplicative actuation channels. The sense of Control Capacity is tight for answering questions of stabilizability for scalar linear systems — a system is stabilizable through an actuation channel if and only if the Control Capacity of that actuation channel is larger than the log of the unstable open-loop eigenvalue. For second-moment senses of stability, our result recovers the classic uncertainty-threshold principle result. However, our formulation can also deal with any other moment. The limits of higher and higher moment senses of stability correspond to a “zero-error” sense of Control Capacity and taking the limit to weaker-andweaker moments corresponds to a “Shannon” sense of Control Capacity.
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Evaluating channels for Control: Capacity reconsidered
Proceedings of the 2000 American Control Conference. ACC (IEEE Cat. No.00CH36334), 2000Co-Authors: Anant SahaiAbstract:We show that Shannon's classical notion of Capacity is not enough to characterize a communication channel if we intend to use that channel as a part of a feedback loop. This is done by considering the stabilization problem for a simple discrete time linear system. While classical Capacity is not enough, we show by example that the stricter notion of Shannon's zero-error Capacity is conservative. We finish by introducing a new parametric notion of Capacity that we call "any-time Capacity" and evaluate it for two channels with feedback: the continuous valued additive white Gaussian noise channel and the binary erasure channel.
Oliver Dickhäuser - One of the best experts on this subject based on the ideXlab platform.
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On the relationship between need for cognition and self-Control Capacity
2012Co-Authors: Alex Bertrams, Oliver DickhäuserAbstract:In the present study, we examined the hypothesis that individuals’ motivational tendency to engage in effortful information processing (i.e., their need for cognition; NFC) is positively related to their self-Control Capacity. This hypothesis was based on previous findings that effortful information processing and self-Control both depend on a joint strength resource, and that this resource is boosted by frequent use. NFC was assessed via questionnaire. One week later, the participants (N = 46) completed a test of self-Control Capacity (Stroop Task). As expected, NFC was positively related to self-Control Capacity but unrelated to general processing speed.
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Passionate thinkers feel better : Self-Control Capacity as mediator of the relationship between need for cognition and affective adjustment
Journal of Individual Differences, 2012Co-Authors: Alex Bertrams, Oliver DickhäuserAbstract:The present study tested a possible explanation for the positive relationship between the motivation to engage in cognitive endeavors (need for cognition, NFC) and indicators of affective adjustment (e.g., higher self-esteem, lower depression) that has been demonstrated in previous studies. We suggest that dispositional self-Control Capacity mediates this relationship, since NFC has been found to be related to self-Control Capacity, and self-Control Capacity is crucial for adjustment. NFC, dispositional self-Control Capacity, self-esteem, habitual depressive mood, and tendency to respond in a socially desirable manner were measured among 150 university students via self-report. Regression analyses and Sobel tests revealed that self-Control Capacity was a potential mediator of the positive relationship between NFC and affective adjustment. The findings were robust in terms of social desirability.
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Dispositional Self-Control Capacity and Trait Anxiety as Relates to Coping Styles
Psychology, 2011Co-Authors: Chris Englert, Alex Bertrams, Oliver DickhäuserAbstract:In the present article, we analyzed the relationship between dispositional self-Control Capacity, trait anxiety, and coping styles. Since self-Control is often crucial for adapting one’s behavior to be positive, we predicted that dispositional differences in the Capacity to exert self-Control play a role in determining individuals coping styles. To test this assumption, we assessed participants’ (N = 163) dispositional self-Control Capacity using the Self-Control Scale, and their dispositional coping styles by using the short version of the German Coping Questionnaire SVF78 (German: Stressverarbeitungsfragebogen). A path analysis supported our hypothesis; higher levels of dispositional self-Control Capacity were positively associated with positive coping style and negatively associated with negative coping style. Basing on attentional Control theory, we further assumed that this relationship was mediated by trait anxiety. In a second study based on a sample of N = 98 participants, we additionally applied the trait version of the State-Trait Anxiety Inventory. The results of a path analysis revealed that trait anxiety mediated the relationship between dispositional self-Control Capacity and coping styles. The results suggest that it may be useful to take a closer look at the role of self-Control in the anxiety-coping relationship
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High-School Students' Need for Cognition, Self-Control Capacity, and School Achievement: Testing a Mediation Hypothesis.
Learning and Individual Differences, 2009Co-Authors: Alex Bertrams, Oliver DickhäuserAbstract:In the present article, we examine the hypothesis that high-school students' motivation to engage in cognitive endeavors (i.e., their need for cognition; NFC) is positively related to their dispositional self-Control Capacity. Furthermore, we test the prediction that the relation between NFC and school achievement is mediated by self-Control Capacity. A questionnaire study with grade ten high-school students (N = 604) revealed the expected relations between NFC, self-Control Capacity, and school achievement. Sobel tests showed that self-Control Capacity mediated the relation between NFC and school grades as well as grade retention.
Alex Bertrams - One of the best experts on this subject based on the ideXlab platform.
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The expression of ego depletion: Thin slices of nonverbal behavior as cues to momentary self-Control Capacity
Social Psychology, 2019Co-Authors: Philip Furley, Chris Englert, Sebastian Kohlhaas, Arne Nieuwenhuys, Alex BertramsAbstract:Abstract. Is depleted self-Control Capacity detectable from thin slices of behavior? In four video-conditions (early-depleted; early-non-depleted; late-depleted; late-non-depleted) untrained observ...
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Higher self-Control Capacity predicts lower anxiety-impaired cognition during math examinations
Frontiers in psychology, 2016Co-Authors: Alex Bertrams, Roy F. Baumeister, Chris EnglertAbstract:We assumed that self-Control Capacity, self-efficacy, and self-esteem would enable students to keep attentional Control during tests. Therefore, we hypothesized that the three personality traits would be negatively related to anxiety-impaired cognition during math examinations. Secondary school students (N = 158) completed measures of self-Control Capacity, self-efficacy, and self-esteem at the beginning of the school year. Five months later, anxiety-impaired cognition during math examinations was assessed. Higher self-Control Capacity, but neither self-efficacy nor self-esteem, predicted lower anxiety-impaired cognition 5 months later, over and above baseline anxiety-impaired cognition. Moreover, self-Control Capacity was indirectly related to math grades via anxiety-impaired cognition. The findings suggest that improving self-Control Capacity may enable students to deal with anxiety-related problems during school tests.
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On the relationship between need for cognition and self-Control Capacity
2012Co-Authors: Alex Bertrams, Oliver DickhäuserAbstract:In the present study, we examined the hypothesis that individuals’ motivational tendency to engage in effortful information processing (i.e., their need for cognition; NFC) is positively related to their self-Control Capacity. This hypothesis was based on previous findings that effortful information processing and self-Control both depend on a joint strength resource, and that this resource is boosted by frequent use. NFC was assessed via questionnaire. One week later, the participants (N = 46) completed a test of self-Control Capacity (Stroop Task). As expected, NFC was positively related to self-Control Capacity but unrelated to general processing speed.
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How minimal grade goals and self-Control Capacity interact in predicting test grades
Learning and Individual Differences, 2012Co-Authors: Alex BertramsAbstract:The present research examined the prediction of school students' grades in an upcoming math test via their minimal grade goals (i.e., the minimum grade in an upcoming test one would be satisfied with). Due to its significance for initiating and maintaining goal-directed behavior, self-Control Capacity was expected to moderate the relation between students' minimal grade goals and their actual grades. Self-Control Capacity was defined as the dispositional Capacity to override or alter one's dominant response tendencies. Prior to a scheduled math test, 172 vocational track students indicated their minimal grade goal for the test and completed a measure of self-Control Capacity. The test grade was assessed at a second time of measurement. As expected, minimal grade goals more strongly predicted the actual test grades the higher the students' self-Control Capacity. Implications can be seen in terms of optimizing the prediction and advancement of academic performance.
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Passionate thinkers feel better : Self-Control Capacity as mediator of the relationship between need for cognition and affective adjustment
Journal of Individual Differences, 2012Co-Authors: Alex Bertrams, Oliver DickhäuserAbstract:The present study tested a possible explanation for the positive relationship between the motivation to engage in cognitive endeavors (need for cognition, NFC) and indicators of affective adjustment (e.g., higher self-esteem, lower depression) that has been demonstrated in previous studies. We suggest that dispositional self-Control Capacity mediates this relationship, since NFC has been found to be related to self-Control Capacity, and self-Control Capacity is crucial for adjustment. NFC, dispositional self-Control Capacity, self-esteem, habitual depressive mood, and tendency to respond in a socially desirable manner were measured among 150 university students via self-report. Regression analyses and Sobel tests revealed that self-Control Capacity was a potential mediator of the positive relationship between NFC and affective adjustment. The findings were robust in terms of social desirability.
Jafar Yazdi - One of the best experts on this subject based on the ideXlab platform.
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Optimal Allocation of Flood Control Capacity for Multi-Reservoir Systems Using Multi-Objective Optimization Approach
Water Resources Management, 2017Co-Authors: Ali Moridi, Jafar YazdiAbstract:Operation of multi-reservoir systems during flood periods is of great importance in the field of water resources management. This paper proposes a multi-objective optimization model with new formulation for optimal operation of multi-reservoir systems. In this model, the release rate and the flood Control Capacity of each reservoir is considered as decision variable and the resulting nonlinear non-convex multi-objective optimization problem is solved with e-constraint method through the mixed integer linear programming (MILP). Objective functions of the model are minimizing the flood damage at downstream sites and the loss of hydropower generation. The developed model is used to determine optimal operating strategies for Karkheh multi-reservoir system in southwestern Iran. For this purpose, the model is executed in two scenarios based on “two-reservoir” and “six-reservoir” systems and for floods with return periods of 25 and 50 years. The results show that in two-reservoir system, flood damage is at least about 114 million dollars and cannot be mitigated any further no matter how hydropower generation is managed. But, in the case of developing all six reservoirs, optimal strategies of coordinated operation can mitigate and even fully prevent flood damage.
Jan Retelsdorf - One of the best experts on this subject based on the ideXlab platform.
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The need for self-Control in achievement tests: Changes in students’ state self-Control Capacity and effort investment
Social Psychology of Education, 2018Co-Authors: Christoph Lindner, Gabriel Nagy, Jan RetelsdorfAbstract:In the present research, we investigated the relation between changes in students’ state self-Control Capacity and their motivational test-taking effort over the course of an achievement test. Thereby, we considered trait self-Control as a major predictor of achievement-related behavior as a covariate. N = 1840 apprentices repeatedly rated their state self-Control Capacity and the test-taking effort they invested while working on a 140-min achievement test in mathematics and science. Using growth curve analyses, our results revealed correlated decreases in state self-Control Capacity and the test-taking effort invested over the course of the test. Furthermore, we found that trait self-Control helped to keep state self-Control Capacity and test-taking effort at a higher level over the course of the test. Our results support the assumption of the process model of self-Control that waning self-Control Capacity is reflected in reduced motivational effort. Furthermore, our findings provide evidence that self-Control might play a crucial role in students’ test-taking behavior in large-scale assessment studies. By modeling changes in state self-Control Capacity and effort investment while considering trait self-Control, we provide an alternative approach for investigating self-Control-dependent processes and the underlying mechanisms of self-Control in achievement situations.
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The Need for Self-Control in Achievement Tests: Changes in Students’ State Self-Control Capacity and Effort Investment
2018Co-Authors: Christoph Lindner, Gabriel Nagy, Jan RetelsdorfAbstract:In the present research, we investigated the relation between changes in students’ state self-Control Capacity and their motivational test-taking effort over the course of an achievement test. Thereby, we considered trait self-Control as a major predictor of achievement-related behavior as a covariate. N = 1,840 apprentices repeatedly rated their state self-Control Capacity and the test-taking effort they invested while working on a 140-minute achievement test in mathematics and science. Using growth curve analyses, our results revealed correlated decreases in state self-Control Capacity and the test-taking effort invested over the course of the test. Furthermore, we found that trait self-Control helped to keep state self-Control Capacity and test-taking effort at a higher level over the course of the test. Our results support the assumption of the process model of self-Control that waning self-Control Capacity is reflected in reduced motivational effort. Furthermore, our findings provide evidence that self-Control might play a crucial role in students’ test-taking behavior in large-scale assessment studies. By modeling changes in state self-Control Capacity and effort investment while considering trait self-Control, we provide an alternative approach for investigating self-Control-dependent processes and the underlying mechanisms of self-Control in achievement situations.