Top-down feedback does not benefit speech recognition; on the contrary, it can hinder it. No experimental data imply that feedback loops are required for speech recognition. Feedback is accordingly unnecessary and spoken word recognition is modular. To defend this thesis, we analyse lexical involvement in phonemic decision making. TRACE (McClelland & Elman 1986), a model with feedback from the lexicon to prelexical processes, is unable to account for all the available data on phonemic decision making. The modular Race model (Cutler (...) & Norris 1979) is likewise challenged by some recent results, however. We therefore present a new modular model of phonemic decision making, the Merge model. In Merge, information flows from prelexical processes to the lexicon without feedback. Because phonemic decisions are based on the merging of prelexical and lexical information, Merge correctly predicts lexical involvement in phonemic decisions in both words and nonwords. Computer simulations show how Merge is able to account for the data through a process of competition between lexical hypotheses. We discuss the issue of feedback in other areas of language processing and conclude that modular models are particularly well suited to the problems and constraints of speech recognition. Key Words: computational modeling; feedback; lexical processing; modularity; phonemic decisions; reading; speech recognition; word recognition. (shrink)
Spontaneous self-corrections in speech pose a communication problem; the speaker must make clear to the listener not only that the original utterance was faulty, but where it was faulty and how the fault is to be corrected. Prosodic marking of corrections - making the prosody of the repair noticeably different from that of the original utterance - offers a resource which the speaker can exploit to provide the listener with such information. A corpus of more than 400 spontaneous speech repairs (...) was analysed, and the prosodic characteristics compared with the syntactic and semantic characteristics of each repair. Prosodic marking showed no relationship at all with the syntactic characteristics of repairs. Instead, marking was associated with certain semantic factors: repairs were marked when the original utterance had been actually erroneous, rather than simply less appropriate than the repair; and repairs tended to be marked more often when the set of items encompassing the error and the repair was small rather than when it was large. These findings lend further weight to the characterization of accent as essentially semantic in function. (shrink)
This paper is the report of a meetingthat gathered many of the UK's most senioranimal scientists with representatives of thefarming industry, consumer groups, animalwelfare groups, and environmentalists. Therewas strong consensus that the current economicstructure of agriculture cannot adequatelyaddress major issues of concern to society:farm incomes, food security and safety, theneeds of developing countries, animal welfare,and the environment. This economic structure isbased primarily on competition betweenproducers and between retailers, driving foodprices down, combined with externalization ofmany costs. These issues must be addressed (...) by acombination of legislation, restructuring ofthe market, and use of public funds. Themeeting included workshops that made otherrecommendations for research and education. Themost urgent requirement is recognition thatchange is needed and development of a visionfor what that change must achieve. (shrink)
Abstract This essay draws upon Gramsci?s understandings of law and of the philosophy of praxis to develop a critical analysis of international law in the constitution and potential revolutionary transformation of the contemporary global political economy. The analysis illustrates the analytical utility of Gramscian conceptions of historical bloc and hegemony in capturing the significance of international law as an effective historical force. It also extends these conceptions, theoretically, by arguing that the global political economy is undergoing a process of juridification (...) in which a commodified legal form provides the template for economic and political regulation. The commodity form theory of law is presented as the key to understanding the significance of international law under the culture of global capitalism. (shrink)
An analysis is presented of the significance and consequent limitations on the applicability of the von Neumann measurement postulate in quantum mechanics. Directly observable quantities, such as the expectation value of the velocity operator, are distinguished from mathematical constructs, such as the expectation value of the canonical momentum, which are not directly observable. A simple criterion to distinguish between the two types of operators is derived. The non-observability of the electromagnetic four-potentials is shown to imply the non-measurability of the canonical (...) momentum. The concept of a mechanical gauge is introduced and discussed. Classically the Lagrangian is nonunique within a total time derivative. This may be interpreted as the freedom of choosing a “mechanical” (M) gauge function. In quantum mechanics it is often implicitly assumed that the M-gauge vanishes. However, the requirement that directly observable quantities be independent of the arbitrary mechanical gauge is shown to lead to results analogous to those derived from the requirement of electromagnetic gauge independence of observables. The significance of the above to the observability of transition amplitudes between field-free energy eigenstates in the presence (and absence) of electromagnetic fields is discussed. E- and M-gauge independent transition amplitudes between field-free energy eigenstates in the absence of electromagnetic fields are defined. It is shown that, in general, such measurable amplitudes cannot be defined in the presence of externally applied time-dependent fields. Transition amplitudes in the presence of time-independent fields are discussed. The path dependence of previous derivations of E-gauge independent Hamiltonians and/or transition amplitudes in the presence of electromagnetic fields are related to the inherent M-gauge dependence of these quantities in the presence of such fields. (shrink)
Our world is littered with examples of the cannibalisation by secondary authors of the thoughts of original thinkers, rehashed as rule-books and manuals on how to live our lives. No such distortion of an idea has had the lasting success of Saint Paul’s corruption of the life and thoughts of Jesus of Nazareth—man or myth we’ll never know. Nietzsche’s over quoted remark, “God is dead,” belies his frustration that in 2,000 years, Western civilisation has not invented for itself a new (...) god. His project of exposing Paul as a charlatan in his penultimate work, The Anti-Christ, hardly disguises Nietzsche’s belief that he could have done a better job, in his case celebrating everything that Christianity stood against: the lost glories of our ancient past symbolising our ‘natural’ human instincts. This essay reassesses assumptions about Nietzsche and his intentions in writing The Anti-Christ to reveal the philosopher’s deep affinity for the original, pre-Christian sage,who provided the main character and plot for Paul’s fiction. (shrink)
Language production and comprehension are intimately interrelated; and models of production and comprehension should, we argue, be constrained by common architectural guidelines. Levelt et al.'s target article adopts as guiding principle Ockham's razor: the best model of production is the simplest one. We recommend adoption of the same principle in comprehension, with consequent simplification of some well-known types of models.
Si oblitus fuero tui, Jerusalem, oblivioni detur dextera mea.” When Jerome commented on Ps. 136.5, he interpreted the passage allegorically. Sitting in exile by the waters of Babylon, the Israelites had hung their harps on the willows and, in a foreign land, would not sing the songs of Zion. Yet they refused to forget their origin, preferring, as King James's translators put it, that “my right hand forget her cunning.” Jerome observes that this is always the hand whose work remembers (...) the Lord. Yet clearly, by the early fifth century, the idea of manual dexterity had become a trope, a figure in some higher argument. Augustine compares the “lower gods”, reduced to performing menial tasks in the administration of the universe, to workers in the silversmiths' quarter through whose many hands a vessel passes before it is finished, even if it could have been perfected by any skilled member of their team. Slightly more pragmatically, Justinian's Digest mentions a piece of silver plate, brought on approval to a client's house by a uascularius but then inadvertently destroyed, as an instance actionable under the laws of contract. (shrink)