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This paper reports further development and applications of a computational model permitting analysis of frequency response characteristics of simulated neurons. The original single‐neuron model, as described by Peddicord and Sampson in 1974, is briefly reviewed here. There follows a thorough description of a new interactive implementation of the model on a PDP‐11/45. The implementation permits high‐speed simulation of large neural networks, and is designed for easy use by investigators with no special knowledge of computers or programming. Experiments with the new system have included the design of improved bandpass filters, pacemaker neurons and networks, and a cerebellar circuit. Simulation results are presented and, in the last case, compared with available physiological data. The paper concludes with a critique of the system, suggestions for further experiments, and a comparison with the simulation system developed by Perkel. Two appendices document the system data structures and show a sample simulation run.

A reproductive plan is a type of adaptive procedure devised by Holland which embodies many principles found in the adaptation of natural systems through evolution. This study develops a reproductive meta‐plan, an adaptive procedure that controls the modification of parameter values in a reproductive plan. After a brief review of Holland's formalization of reproductive plans, a non‐reproductive meta‐plan devised by Cavicchio is discussed. In response to some of the limitations of Cavicchio's approach, a reproductive meta‐plan is developed. Experiments with computer implementations of both meta‐plans show improvement in a reproductive plan's utility gain when the reproductive meta‐plan is used.

The decline in neighbourhoods resulting from globalization and technology, which trigger high rise buildings, has been discussed by several disciplines. Changes in life styles destroy not only traditional neighbourhoods but also open spaces. This situation leads to a decrease in both collective efficacy and neighbourhood attachment. Place attachment would play an important role in overcoming fear of crime and low security perception, which are the most substantial social problems of today's cities. Therefore, it is important that urban designers, architects and landscape architects develop design policies that contribute to place attachment. The aim of this study is to develop models that explain neighbourhood attachment by collective efficacy, open space quality and socio-demographic variables. Kuzguncuk neighbourhood was chosen as a study area because of its unique character, socio-cultural diversity and the collective power that is due to the various social groups in the neighbourhood. This study seeks to answer the following question: Do open space quality, collective efficacy and socio-demographic factors predict neighbourhood attachment? We examined whether attachment to a neighborhood is associated with collective power and perception of open space quality by inhabitants. Therefore, neighbourhood attachment and its predictors were studied in this specific neighbour-hood. Face to face interviews were conducted with 313 inhabitants using a stratified sampling method. Descriptive statistics and hierarchical linear modelling analyses were used to predict neighbourhood attachment. We found that collective efficacy, open space quality, place of birth and length of residence were predictors of neighbourhood attachment. Therefore, to prevent social problems, such as fear of crime, low security perception, loneliness and segregation, policy makers, designers, planners and social scientists should focus on neighbourhoods that have small communities. In conclusion, the quality perception of open spaces should be considered to increase neighbourhood attachment, and inhabitants should be encouraged to use public spaces in which social ties can develop.

The purpose of this paper is to examine the relationship between neighbourhood characteristics and fear of crime, and further explore how this relationship is mediated by collective efficacy. The background to this is that while research, mainly based on the experiences of western countries is conclusive on how collective efficacy plays a mediating role between neighbourhood structural characteristics and fear of crime, the situation in developing countries remains poorly researched.

The study drew from a baseline survey conducted in different socio-economic neighbourhoods in four cities in Ghana. With regards to the analysis, results from a series of ordinary least square multiple regression models were used to develop a path diagram to explain the direct and indirect relationships at the various study neighbourhoods.

Results from the study showed variations of the extent of neighbourhood effect on fear of crime and collective efficacy in the different socio-economic neighbourhoods. More importantly, the study revealed that collective efficacy mediated the effect of a number of neighbourhood characteristics on fear of crime in low-income neighbourhoods compared to middle- and high-income neighbourhoods.

The conclusion of the study brings to the fore the relevance of collective efficacy as a vehicle for building safer communities in Ghana since it relies on local initiatives in addressing criminogenic problems. More importantly, it is suggested that formal crime prevention efforts should be integrated with informal crime control measures, particularly in low-income neighbourhoods.

Using extensive survey data collected in Ghana, the study examines the applicability of collective efficacy, a western-based socio-ecological theory in a developing country context.

Reports on a field experiment in Dayton, Ohio, where the police department has no specialized traffic division, hence traffic enforcement is part of the routine assignment. Aims to measure the effects of traffic law enforcement on crime, arrests and traffic accidents. Presents data covering all index arrests and special arrests involving weapons, drugs and offenders driving under influence, plus all reported traffic accidents. Contrary to other research, fails to detect a relationship between traffic enforcement and crime. Investigates possible reasons for this.

What are the long term consequences associated with serving as a state FFA officer? Using a semi-structured interview format, selected state FFA officers from a twenty year time span were interviewed to assess their perceptions of and assets attributed to their experiences as a state officer. Results indicated that past state officers, regardless of when they served, noted positive leadership development, personal growth, and a heightened level of community awareness. Additionally, experiences and subsequent engagement related to their term confirmed four key features of positive adolescent development, which are, a sense of industry and competence; a sense of identity; a sense of control over one’s fate; and connectedness to others (CSR Inc, 1997).

WE hope that all London librarians will give full consideration to the project of the London Branch of the Library Association to provide a union catalogue of the non‐fiction Stocks of Metropolitan libraries. They are to be asked if they will co‐operate in the scheme by providing cards of their Stock of uniform size, or by making some contribution (a more difficult matter this) to the cost of the catlogue. Such a catalogue kept at the Central Library for Students, combined with the telephone and general goodwill, would bring about a co‐ordination of libraties on a voluntary basis with results in good as yet scarcely realized. The idea is not novel; it was rejected a score of years ago as visionary or impractable. It may have been visionary then; it is not so now. Modern librarians simply must get together if they wish to avoid being made to do so.

This study examines the relationship between age, physical violence and non‐physical abuse within the context of intimate partner violence (IPV). It tests the hypothesis that while the prevalence of physical violence is lower among older women, other forms of intimate partner violence are not related to age. The study uses data from the Michigan Violence Against Women Survey to measure physical violence and two forms of non‐physical abuse: psychological vulnerability and autonomy‐limiting behavior. Findings support the hypothesis that the rate of physical abuse is negatively related to age but the rate of nonphysical abuse is not. By expanding the definition of IPV to include other forms of abusive behavior, the study finds that older women have IPV prevalence rates similar to younger women. This raises the question of whether batterers alter their means of power and control by emphasizing non‐physical abuse rather than continuing to use physical violence that exposes them to formal and informal social controls and sanctions.

The purpose of this paper is to verify the impacts of the transaction costs rationale on economic agents’ innovative results when they engage in European R & D networks, supplying both firms and policymakers with empirical support for improved decision making toward economic competitiveness and construction of the European research area. Furthermore, unlike many transaction cost economics assessments, the authors evaluate the existence of transaction costs following a dynamic framework of analysis (instead of using solely ex ante governance choice as a driver of inter-firm “friction” management), offering a novel perspective on these phenomena.

Data consist of firm-level information from Eureka’s Final Reports (1995-2006) for Spanish, Italian, French, British and German firms. Empirical assessments were performed through a two-step approach of direct and indirect effects of network management and potential sources of disturbances. Ordinal regressions were applied in order to identify transaction costs’ relevance as drivers of firms’ technological and commercial outcomes, as well as on managerial quality of alliances. Statistical controls include microeconomic and project-specific variables.

Results highlight the role played by transactional aspects as drivers of companies’ outcomes and managerial complexity. Furthermore, the authors find robust evidence that formal ex ante governance structures are incapable of satisfactorily addressing dynamic disturbances that take place within R & D networks. Whereas such findings are directly related to existing transaction costs, the authors find no support for the usual variables attributed to increased complexity in international inter-firm relationships.

Self-selection issues are inherently related to the research instrument (i.e. Eureka’s Reports), while further firm-level data could not be obtained since confidentiality issues protected companies’ names and sectors. Also, network-level data are not available, allowing the evaluation of individual perceptions only.

While literature addresses the issue of transaction costs in R & D networks via theoretical assumptions and rough proxies, this assessment offers an in-depth evaluation of a set of valuable indicators with direct implications for researchers, managers and policymakers. Main contributions concern the identification of dynamic interactions (and their respective disturbances) as a key feature of the overall performance of R & D networks, stressing the non-linearity of economic processes in these hybrid relationships, an issue that has been poorly tackled by previous empirical investigations.

The purpose of this paper is to fill the theoretical void in the discussion of effects of alliance portfolios on firm performance by studying the moderating role of a firm’s strategic positioning.

A fixed effects, autoregressive panel model on a comprehensive, longitudinal sample of large and medium-sized publicly traded companies in the USA.

The effect of alliance portfolios on firm performance is conditional on the firm’s strategic positioning.

The results may not be applicable to firms outside the USA or small firms.

Executives should craft their alliance portfolios while considering the strategic positioning of their firms.

This paper presents the first study of alliance portfolios that uses a comprehensive, multi-industry sample while considering firms’ strategic positioning. The paper is the first to jointly study characteristics of alliance portfolios and firm strategies.