Combining forecasts: An application to elections

We summarize the literature on the effectiveness of combining forecasts by assessing the conditions under which combining is most valuable. Using data on the six US presidential elections from 1992 to 2012, we report the reductions in error obtained by averaging forecasts within and across four election forecasting methods: poll projections, expert judgment, quantitative models, and the Iowa Electronic Markets. Across the six elections, the resulting combined forecasts were more accurate than any individual component method, on average. The gains in accuracy from combining increased with the numbers of forecasts used, especially when these forecasts were based on different methods and different data, and in situations involving high levels of uncertainty. Such combining yielded error reductions of between 16% and 59%, compared to the average errors of the individual forecasts. This improvement is substantially greater than the 12% reduction in error that had been reported previously for combining forecasts.     

Toward a structural view of co-opetition in supply networks

Co-opetition, or simultaneous competition and cooperation, in the supply chain management literature has been treated as a dyadic relational phenomenon where the buyer's strategy is considered to be the primary driver. In this paper, we move beyond the dyadic view and propose a theory of co-opetition in supply networks. We argue that as firms within a supply network interact over time to access, share, and transform resources, new ties between firms are formed and existing ties dissolve, giving rise to co-opetition dynamics at the network level. Taking a configurational approach, we employ the inter-related dimensions of ties between firm, firm-level task, network-level objective, and governance to specify four practical supply network archetypes that cover a wide range of economic activities. We then explain how coopetitive relationships may evolve in these supply network archetypes. Specifically, we discuss how relationships form or dissolve in these archetypes and how local structural changes lead to co-opetition dynamics at the network level. We also discuss the implications of such dynamics from a managerial perspective.     

Detecting big structural breaks in large factor models

Time invariance of factor loadings is a standard assumption in the analysis of large factor models. Yet, this assumption may be restrictive unless parameter shifts are mild (i.e., local to zero). In this paper we develop a new testing procedure to detect big breaks in these loadings at either known or unknown dates. It relies upon testing for parameter breaks in a regression of one of the factors estimated by Principal Components analysis on the remaining estimated factors, where the number of factors is chosen according to Bai and Ng’s (2002) information criteria. The test fares well in terms of power relative to other recently proposed tests on this issue, and can be easily implemented to avoid forecasting failures in standard factor-augmented (FAR, FAVAR) models where the number of factors is a priori imposed on the basis of theoretical considerations.     

Bayesian exploratory factor analysis

This paper develops and applies a Bayesian approach to Exploratory Factor Analysis that improves on ad hoc classical approaches. Our framework relies on dedicated factor models and simultaneously determines the number of factors, the allocation of each measurement to a unique factor, and the corresponding factor loadings. Classical identification criteria are applied and integrated into our Bayesian procedure to generate models that are stable and clearly interpretable. A Monte Carlo study confirms the validity of the approach. The method is used to produce interpretable low dimensional aggregates from a high dimensional set of psychological measurements.     

Neighborhood as Spatial Project: Making the Urban Order on the Downtown Brooklyn Waterfront

This article argues for a reconceptualization of one of the most basic concepts in urban studies: the neighborhood. Traditionally neighborhoods have been understood as clearly bounded, quasi‐Westphalian containers or as ‘natural areas’ of urban community. But this approach is widely acknowledged to be under‐theorized. And it fails to account for the ways in which the production of neighborhood is inherently political and often conflictual. After reviewing the ways in which neighborhood has been used in urban sociology and urban planning, this article offers a critical conception of neighborhoods as ‘spatial projects’ on the submetropolitan scale. This approach captures the ways in which neighborhoods are not abstract spaces on a city map, but the uneven, unequal products of complex, ongoing struggles between various groups and institutions. This approach is developed through an ethnographic and historical case study of neighborhood formation in one part of Brooklyn, New York. The article concludes with a discussion of how the language of spatial projects refocuses urban research on the political and economic forces that produce neighborhood in the contemporary city.     

LGBT Neighbourhoods and ‘New Mobilities’: Towards Understanding Transformations in Sexual and Gendered Urban Landscapes

In this article we apply insights from ‘new mobilities’ approaches to understand the shifting sexual and gendered landscapes of major cities in the global North. The empirical context is the purported ‘demise’ of traditional gay villages in Toronto, Canada and Sydney, Australia, and the emergence of ‘LGBT neighbourhoods’ elsewhere in the inner city. We reinterpret the historical geography of twentieth century LGBT lives and the associated ‘rise and fall’ of gay enclaves through the lens of the ‘politics of mobility’. In this reading, it is apparent that multifaceted movements — migration, physical and social mobility, and motility — underpin the formation of gay enclaves and recent transformations in sexual and gendered landscapes. After the second world war, LGBT communities in the global North were embedded in specific historical geographies of mobility and we trace these in the Canadian and Australian contexts. The ‘great gay migration’ from the 1960s to the 1980s has been joined by new LGBT constellations of mobility in the 2000s, and these have imprinted upon the sexual and gendered landscapes of Toronto and Sydney.     

Gentrification in Hong Kong? Epistemology vs. Ontology

This article examines the transferability of the concept of gentrification away from its Anglo‐American heartland to the cities of Asia Pacific and specifically Hong Kong. An epistemological argument challenges such theoretical licence, claiming that conceptual overreach represents another example of Anglo‐American hegemony asserting the primacy of its concepts in other societies and cultures. Past research suggests that if gentrification exists in Asia Pacific cities it bears some definite regional specificities of urban form, state direction and, most surprising from a Western perspective, a potentially progressive dimension for some impacted residents. Closer examination of urban discourse in Hong Kong is conducted through analysis of English and Chinese language newspapers. In both instances, gentrification is barely used to describe the pervasive processes of urban redevelopment, which otherwise receive abundant coverage. Interviews with local housing experts confirm the marginality of gentrification in academic and public discourse, and the power of a local ideology that sees urban (re)development unproblematically as a means of upward social mobility. However, in the decade‐long housing bust after 1997, growing inequality has encouraged a nascent class analysis of the property market, an ontological awakening that may prove more favourable to the identification of gentrification in an Asia Pacific idiom.     

Understanding employee preferences for investing in employer stock: evidence from France

In this article, we broaden the focus of existing research on employee stock purchase plans by analysing employee preferences for investing in employer stock as a construct distinct from actual investment behaviour. In our analysis of original survey data in a sample of 900 employees in four French companies, we find that employee preferences are influenced by two common cognitive heuristics (representativeness and familiarity), organisational commitment, the perceived quality of corporate communications about these plans and perceived managerial commitment to employee ownership. We did not find, however, that risk aversion, turnover intentions or perceived employee involvement in decision making influenced preferences for investing in employer stock. Our findings have both theoretical and practical implications for understanding and operating these types of employee benefit plans, which are becoming more common across the globe.     

ASSESSING THE EFFECT OF PUBLIC SUBSIDIES ON FIRM R&D INVESTMENT: A SURVEY

This survey examines the empirical literature on the relationship between public R&D subsidies and private R&D investment over the past five decades. The survey reveals a considerable heterogeneity of empirical results that cannot be explained fully by methodological issues. We aim to provide further explanations of the possible causes of that heterogeneity. In particular, we emphasise a set of issues that, in our view, are critical to understanding the potential effect of public R&D subsidies on private R&D spending. Special attention is paid to the dynamic aspects and composition of firm R&D, the constraints faced by the firm (such as financial constraints), and the amount and source of public subsidies. None of these issues have been investigated in depth. We formulate a set of research assumptions to guide future empirical research in this field.