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Rule-based Evolutionary Online Learning Systems: LEARNING BOUNDS, CLASSIFICATION, AND PREDICTION
, 2004
"... Rule-based evolutionary online learning systems, often referred to as Michigan-style learning classifier systems (LCSs), were proposed nearly thirty years ago (Holland, 1976; Holland, 1977) originally calling them cognitive systems. LCSs combine the strength of reinforcement learning with the genera ..."
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Cited by 54 (10 self)
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Rule-based evolutionary online learning systems, often referred to as Michigan-style learning classifier systems (LCSs), were proposed nearly thirty years ago (Holland, 1976; Holland, 1977) originally calling them cognitive systems. LCSs combine the strength of reinforcement learning with the generalization capabilities of genetic algorithms promising a flexible, online generalizing, solely reinforcement dependent learning system. However, despite several initial successful applications of LCSs and their interesting relations with animal learning and cognition, understanding of the systems remained somewhat obscured. Questions concerning learning complexity or convergence remained unanswered. Performance in different problem types, problem structures, concept spaces, and hypothesis spaces stayed nearly unpredictable. This thesis has the following three major objectives: (1) to establish a facetwise theory approach for LCSs that promotes system analysis, understanding, and design; (2) to analyze, evaluate, and enhance the XCS classifier system (Wilson, 1995) by the means of the facetwise approach establishing a fundamental XCS learning theory; (3) to identify both the major advantages of an LCS-based learning approach as well as the most promising potential application areas. Achieving these three objectives leads to a rigorous understanding
The Cocktail Party Problem
, 2005
"... This review presents an overview of a challenging problem in auditory perception, the cocktail party phenomenon, the delineation of which goes back to a classic paper by Cherry in 1953. In this review, we address the following issues: (1) human auditory scene analysis, which is a general process car ..."
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Cited by 47 (0 self)
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This review presents an overview of a challenging problem in auditory perception, the cocktail party phenomenon, the delineation of which goes back to a classic paper by Cherry in 1953. In this review, we address the following issues: (1) human auditory scene analysis, which is a general process carried out by the auditory system of a human listener; (2) insight into auditory perception, which is derived from Marr’s vision theory; (3) computational auditory scene analysis, which focuses on specific approaches aimed at solving the machine cocktail party problem; (4) active audition, the proposal for which is motivated by analogy with active vision, and (5) discussion of brain theory and independent component analysis, on the one hand, and correlative neural firing, on the other.
Doubly distributional population codes: Simultaneous represen tation of uncertainty and multiplicity
, 2003
"... Perceptual inference fundamentally involves uncertainty, arising from noise in sensation and the ill-posed nature of many perceptual problems. Accurate perception requires that this uncertainty be correctly represented, manipulated, and learned about. The choices made by subjects in various psychoph ..."
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Cited by 38 (8 self)
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Perceptual inference fundamentally involves uncertainty, arising from noise in sensation and the ill-posed nature of many perceptual problems. Accurate perception requires that this uncertainty be correctly represented, manipulated, and learned about. The choices made by subjects in various psychophysical experiments suggest that they do indeed take such uncertainty into account when making perceptual inferences, posing the question as to how uncertainty is represented in the activities of neuronal populations. Most theoretical investigations of population coding have ignored this issue altogether; the few existing proposals that address it, do so in such a way that it is fatally conflated with another facet of perceptual problems that also needs correct handling, namely multiplicity (that is, the simultaneous presence of multiple distinct stimuli). We present and validate a more powerful proposal for the way that population activity may encode uncertainty, both distinctly from, and simultaneously with, multiplicity.
A computational model of auditory selective attention
- IEEE Transactions on Neural Networks
, 2004
"... The auditory system must separate an acoustic mixture in order to create a perceptual description of each sound source. It has been proposed that this is achieved by a process of auditory scene analysis (ASA) in which a number of streams are produced, each describing a single sound source. Few compu ..."
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Cited by 22 (2 self)
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The auditory system must separate an acoustic mixture in order to create a perceptual description of each sound source. It has been proposed that this is achieved by a process of auditory scene analysis (ASA) in which a number of streams are produced, each describing a single sound source. Few computer models of ASA attempt to incorporate attentional effects, since ASA is typically seen as a precursor to attentional mechanisms. This assumption may be flawed: recent work has suggested that attention plays a key role in the formation of streams, as opposed to the conventional view that attention merely selects a pre-constructed stream. This study presents a conceptual framework for auditory selective attention in which the formation of groups and streams is heavily influenced by conscious and subconscious attention. This framework is implemented as a computational model comprising a network of neural oscillators which perform stream segregation on the basis of oscillatory correlation. Within the network, attentional interest is modelled as a gaussian distribution in frequency. This determines the connection weights between oscillators and the attentional process- the attentional leaky integrator (ALI). A segment or group of segments are said to be attended to if their oscillatory activity coincides temporally with a peak in the ALI activity. The output of the model is an ‘attentional stream’: a description of which frequencies are being attended at each epoch. The model successfully simulates a range of psychophysical phenomena. Furthermore, a number of predictions are made and a psychophysical experiment is conducted to investigate the time course of attentional allocation in a binaural streaming task. The results support the model prediction that attention is subject to a form of ‘reset ’ when the attentional focus is moved in space. Acknowledgements The inspiration and initial psychophysical data upon which this work is based came from a presentation
Exploration of Behavioral, . . .
, 2004
"... We present an overview for the study of auditory perception and scene analysis through the three main approaches researchers have used to study perception in general: behavioral, physiological, and computational. At the behavioral level, we discuss the principles and origins of auditory scene analys ..."
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Cited by 5 (1 self)
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We present an overview for the study of auditory perception and scene analysis through the three main approaches researchers have used to study perception in general: behavioral, physiological, and computational. At the behavioral level, we discuss the principles and origins of auditory scene analysis, and establish the relationship between auditory scene analysis and auditory masking. Within auditory masking, we note the coexistence of informational and energetic masking, and utilize the ideal time-frequency binary masks in a series of speech intelligibility experiments to isolate the energetic component of speech-on-speech masking. At the physiological level, we propose the adoption of the two-dimensional time-frequency oscillatory correlation representation as a main representation in auditory perception, after reviewing several of the theories and experiments in neurophysiology in effort to find its support. Finally, at the computational level, we extend an existing implementation of oscillatory correlation, LEGION [144], to simulate the major behavioral principles in alternating-tone sequences. Most notably, the decision boundaries of the temporal coherence boundary (TCB) and fission boundary (FB)
On novel reception models for Bottlenose dolphin echolocation
- Proceedings of the Institute of Acoustics, vol.24, Biosonar
, 2001
"... Bottlenose dolphin (Tursiops truncatus) echolocation resolution greatly exceeds measured beampattern and conventional hearing model performance. We explore the idea that teeth might aid conventional hearing. Nerve conduction requires neural delay lines, a requisite that might be met by unexplained s ..."
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Bottlenose dolphin (Tursiops truncatus) echolocation resolution greatly exceeds measured beampattern and conventional hearing model performance. We explore the idea that teeth might aid conventional hearing. Nerve conduction requires neural delay lines, a requisite that might be met by unexplained specialised cell arrangements already reported. Jawbone resonance displays selectivity at 25-35 degrees to one side of the rostrum that suggests the use of ambient noise or a passive sonar mode associated with head scanning. KEY WORDS: dolphin;echolocation;teeth;tursiops;sonar;hearing 2. INTRODUCTION – WHAT IS THE PROBLEM? Dolphins have clearly evolved excellent echolocation capabilities but many aspects of how their biosonar works are still not fully understood. The echolocation system performance depends on three main areas of functionality; the transmit characteristics, the reception characteristics and the central nervous system processing. The major factors that constrain the spatial resolution of
Behavioral measures of signal recognition thresholds in frogs in the presence and absence of chorus-shaped noise
- J. Acoust
, 2009
"... Anuran amphibians are superb animal models for investigating the mechanisms underlying acoustic signal perception amid high levels of background noise generated by large social aggregations of vocalizing individuals. Yet there are not well-established methods for quantifying a number of key measure ..."
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Anuran amphibians are superb animal models for investigating the mechanisms underlying acoustic signal perception amid high levels of background noise generated by large social aggregations of vocalizing individuals. Yet there are not well-established methods for quantifying a number of key measures of auditory perception in frogs, in part, because frogs are notoriously difficult subjects for traditional psychoacoustic experiments based on classical or operant conditioning. A common experimental approach for studying frog hearing and acoustic communication involves behavioral phonotaxis experiments, in which patterns of movement directed toward sound sources indicate the subjects' perceptual experiences. In this study, three different phonotaxis experiments were conducted using the same target signals and noise maskers to compare different experimental methods and analytical tools for deriving estimates of signal recognition thresholds in the presence or absence of "chorus-shaped noise" ͑i.e., artificial noise with a spectrum similar to that of real breeding choruses͒. Estimates of recognition thresholds based on measures of angular orientation, response probabilities, and response latencies were quite similar in both two-choice and no-choice phonotaxis tests. These results establish important baselines for comparing different methods of estimating signal recognition thresholds in frogs tested in various masking noise conditions.
TESTS FOR CALL RESTORATION IN THE GRAY TREEFROG HYLA VERSICOLOR
, 2010
"... ABSTRACT Phonemic restoration, a form of temporal induction, occurs when the human brain compensates for masked or missing portions of speech by filling in obscured or nonexistent sounds. We tested for temporal induction and related abilities in females of the Gray Treefrog Hyla versicolor. The num ..."
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ABSTRACT Phonemic restoration, a form of temporal induction, occurs when the human brain compensates for masked or missing portions of speech by filling in obscured or nonexistent sounds. We tested for temporal induction and related abilities in females of the Gray Treefrog Hyla versicolor. The number of pulses in calls is used by females for assessment of males. Accordingly, an ability to "restore" or interpolate between masked or otherwise sonically degraded portions of calls could help females during mate choice in noisy choruses. In phonotaxis experiments, we employed unmodified calls and those that had a centrally placed gap, a region overlapped by a portion of another call or filtered noise, or replaced with filtered noise. When offered call alternatives with equivalent numbers of clear pulses, we found that females discriminated against calls with gaps two or more times greater than the natural 25 ms interpulse interval. When a gap was replaced with a zone of call overlap or noise (so, again the call durations of the alternatives were unequal), females discriminated either in favour (overlap) of the modified stimuli or failed to discriminate (noise). However, when the unmodified and modified stimuli were the same duration, females discriminated against the latter. Normal calls were also chosen when paired against calls with multiple noise sections. Pulses formed from noise bursts were attractive, but less so than normal pulses. In single speaker tests, standardized rates of movement did not differ between calls containing noise segments of different duration. Our results therefore do not indicate that females of the Gray Treefrog employ a form of temporal induction that is fully restorative. However, the data indicate that acoustically anomalous sections of calls can retain attractive potential provided acoustic energy and pulses are present.
Humpback Whale Song or Humpback Whale Sonar? A Reply to Au et al.
"... Abstract—Au and colleagues ’ arguments against the hypothesis that humpback whale songs function as long-range sonar are based on questionable assumptions rather than on empirical data. Like other echolocating mammals (e.g., bats), singing humpback whales: 1) localize targets in the absence of visua ..."
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Abstract—Au and colleagues ’ arguments against the hypothesis that humpback whale songs function as long-range sonar are based on questionable assumptions rather than on empirical data. Like other echolocating mammals (e.g., bats), singing humpback whales: 1) localize targets in the absence of visual information; 2) possess a highly innervated peripheral auditory system; and 3) modulate the temporal and spectral features of their sounds based on environmental conditions. The sonar equation is inadequate for determining whether humpback whale songs generate detectable echoes from other whales because it does not account for temporal variables that can strongly affect the detectability of echoes. In particular, the sonar equation ignores the fact that much of the noise encountered by singing humpback whales is spectrally and temporally predictable, and that audition in mammals is a dynamic and plastic process. Experiments are needed to test the hypothesis that singing humpback whales listen for and respond to echoes generated by their songs. Index Terms—Baleen whale, cetacean, environmentally-adaptive sonar, low-frequency sonar, mysticete.
Cue combination Computational modeling Population coding Neural variability
, 2008
"... available at www.sciencedirect.com www.elsevier.com/locate/brainres Review Linking neurons to behavior in multisensory perception: A computational review ..."
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available at www.sciencedirect.com www.elsevier.com/locate/brainres Review Linking neurons to behavior in multisensory perception: A computational review
