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Interspecific competition is a major factor influencing the structure of communities. This chapter examines the principles of interspecific completion, defined as a reduction in the population growth rate of one species due to presence of one (or more) other species due to their shared use of limiting resources or active interference. The chapter begins with a presentation of the classic Lotka–Volterra competition model, but quickly moves on to more recent consumer–resource competition models. Conditions leading to competitive exclusion and species coexistence are discussed, as are empirical tests of the predictions of resource competition theory. In general, coexistence requires that each species has a greater negative effect on its own population growth rate than on the population growth rate of another species. Shared predation also can result in species having negative effects on each other’s population growth rate, a condition known as “apparent competition”.

This chapter introduces mathematical and statistical modelling approaches in community ecology. It starts with a conceptual section, continues with mathematical and statistical sections, and ends with a perspectives section. The conceptual section motivates the modelling approaches by providing the necessary background to community ecology. The mathematical sections start with models of two interacting species in homogeneous space, including a model with competitive interactions, a resource–consumer model, and a predator–prey model. The competition model is expanded to heterogeneous space and to the case of many competing species. This model is used to analyse the consequences of habitat loss and fragmentation at the community level. To illustrate the interplay between models and data, the statistical section analyses data generated by the mathematical models, with emphasis on time-series data of two interacting species, point pattern analyses, and joint species distribution models.

The concept of efficiency is used in different ways in economics. First, the practical relevance of models that conclude that tax competition is either Pareto optimal or not is limited, because we do not live in the idealized circumstances of the Pareto frontier. Second, the more relevant criterion of Pareto improvement is silent on the prospect of regulating tax competition because, as previous chapters have shown, the latter has redistributive effects. Third, efficiency as an instrumental value to arbitrate trade-offs between two or more policy goals—a role it plays in optimal tax theory, for example—can in fact be used to show that regulating tax competition is a requirement of efficiency rather than an obstacle to it.

This chapter discusses a neurological implementation of a model that allows for concurrent activation of multiple representations that are distinct from activated areas of long-term memory, which may be domain-specific and involve activations associated with integrated objects arising from the binding of several different sensory features. Rather than referring to a focus of attention, their argument builds on the Desimone and Duncan biased-competition model in which the relative activation of these different representations influences activation elsewhere in the brain and consequently influences action.

This chapter begins with a brief account of the key public sector reforms, tracing the genealogy of the New Public Contracting from the early 1980s through to the present day. It explores the relationship between the New Public Contracting and the New Public Management. It suggests that the UK has been particularly influenced by a market/competition model of public management reform, in comparison with a more restricted ‘managerialist contractualist’ conception that has been dominant in other countries. The chapter shows how the separate administrative and economic functions of the New Public Contracting have nevertheless been brought within a coherent overall policy framework governing public services, through guidance in the form of Better Quality Services (BQS) in central government and the statutory regime of best value in local government. The chapter concludes with a brief discussion of the external constraints on UK policy imposed under international treaty obligations, showing how they relate to fundamental economic rationales for the public contracting policies currently being pursued by New Labour.

Like other biological systems, language emerges as a product of competing motivations that interact at the moment of speaking. These many different motivations are each linked to different timeframes for neural processing, social usage, and consolidation. Functionalist accounts of language usage need to pay increased attention to the ways in which motivations are distributed across timeframes in order to understand how the meshing of motivations at the moment of speaking produces long‐term impacts on speakers and language communities. Adoption of this perspective provides us with ways of integrating the many insights presented in the chapters in the current volume.

This chapter evaluates producer benefits from export variety under the monopolistic competition model. It suggests that self-selection of firms can still be interpreted as a gain from product variety but on the export side of the economy rather than for imports. It also explains that consumer gains from import variety in Marc J. Melitz’s model cancel out with the reduction in domestic varieties when trade is opened and contends that self-selection of firms leads to a constant-elasticity transformation curve between domestic and export varieties.

In this chapter, a number of studies exploring young children's development of grammar within the Competition Model framework (Bates and MacWhinney 1989) are reviewed. It focuses on studies investigating children's ability to comprehend a simple transitive sentence, i.e., their ability to identify its subject and object, and in particular on the role that word order and case marking play in this process in different languages. The results suggest that children can initially process sentences which follow a prototypical pattern of their language and as such provide a number of redundant cues, and that the process of pulling apart individual cues is slow and gradual. The ability to use cues productively with novel items is more delayed and sentences with competing cues remain particularly difficult for a long time. The implications those results have for our understanding of early grammatical development are discussed.

Most work on competing cues in language acquisition has focused on what happens when cues compete within a certain construction. There has been far less work on what happens when constructions themselves compete. This chapter aims to explore how the acquisition mechanism copes when constructions compete in a language. It presents three experimental studies, all of which focus on the acquisition of the syntactic function of word order as a marker of the Theme–Recipient relation in ditransitives. It concludes that there is not only competition between cues but competition between constructions from the very beginning of the language acquisition process.