Tests for an end-of-sample bubble in financial time series

ABSTRACT

In this paper, we examine the issue of detecting explosive behavior in economic and financial time series when an explosive episode is both ongoing at the end of the sample and of finite length. We propose a testing strategy based on a subsampling method in which a suitable test statistic is calculated on a finite number of end-of-sample observations, with a critical value obtained using subsample test statistics calculated on the remaining observations. This approach also has the practical advantage that, by virtue of how the critical values are obtained, it can deliver tests which are robust to, among other things, conditional heteroskedasticity and serial correlation in the driving shocks. We also explore modifications of the raw statistics to account for unconditional heteroskedasticity using studentization and a White-type correction. We evaluate the finite sample size and power properties of our proposed procedures and find that they offer promising levels of power, suggesting the possibility for earlier detection of end-of-sample bubble episodes compared to existing procedures.     

Defamilization/familization measures and women's pension income—The case of Taiwan

This paper examines how defamilization and familization measures can affect women's capacity to accumulate pension income and their subsequent standard of living after retirement. Firstly, it highlights the concepts of defamilization and familization and discusses the potential of these measures in assisting women to save pension income through the “commodification” and “decommodification” of labor. Secondly, it examines the major pension policies and examples of defamilization and familization measures in Taiwan. It shows how the current limited provision of such measures could create “double jeopardy” for women, affecting access to paid employment or resources to enable women who wish to undertake caring responsibilities to do so, ultimately impacting their capacity to accumulate pension income. Thirdly, it suggests ways to strengthen defamilization and familization measures in order to enable women to accumulate sufficient retirement income on the basis of three preconditions: policy attention to the reciprocal relationship between familization/defamilization measures and pension schemes for women; a recognition of differences between women in their preferred strategies to accumulate pension income; and an emphasis on a life course perspective to understand the double jeopardies faced by women in saving for retirement.     

The Role of Gay Identity Confusion and Outness in Sex-Seeking on Mobile Dating Apps Among Men Who Have Sex With Men: A Conditional Process Analysis

Mobile dating apps are now a popular platform for men who have sex with men (MSM) to connect with others. Based on the uses and gratifications (U&G) theory, this study explores the relationship between sex-seeking and the number of casual sex partners met through MSM-based mobile dating apps (Grindr, Jack’d, and SCRUFF). The conditional process analysis (N = 401) shows that this relationship was significant and was mediated by the intensity of app use. That is, sex-seeking indirectly affected the number of casual sex partners through the intensity of app use. Furthermore, gay identity confusion and outness to the world moderated this indirect effect: it was stronger when the user was either more confused about his sexuality or was less out to the world. This research introduces an alternative way to incorporate psychographics variables into the U&G framework.     

Theorizing New Media: Reflexivity,Knowledge, and the Web 2.0*

A recent wave of popular and scholarly discourse has hailed the arrival of the Web 2.0, marking a new generation of Internet users who share and collaborate on popular social networking sites such as MySpace and user‐generated communities such as YouTube and Wikipedia. Social and cultural critics have attempted to take stock of the implications of these various technological changes with specific emphasis on the state of knowledge in contemporary society. This article aims to theoretically examine knowledge in the context of new media technologies with particular attention paid to the notion of “reflexivity.” Focusing on the work of Scott Lash, whose theory of reflexivity radically differs from various other interpretations, I suggest that knowledge, in its modern formulation—as reasoned, stable, and linear—must be rethought for the information age, critiquing some of the predominant scholarly and popular media criticisms that suggests media to be mere enhancements of human forms of communication, knowledge, and sense‐making. I conclude by considering some of the ontological dimensions of the transformations in the dynamics of knowledge in new media technologies.     

A case for using adaptive platforms in the development and implementation of urban-centred adaptive management plans

The recurring challenges in developing and coordinating social frameworks for the effective adaptive management of environmental resources in urban environments may be addressed by developing platforms, similar to those promoted by collective action in the management of common pool resources. This paper compares how these two frameworks perceive and foster social organization vis-à-vis management action, particularly at the local scale of resource use. The significant potential for incorporation of platforms into the adaptive management framework is discussed, based on a set of issues identified in collective action research as important in the development of platforms. An urban-centred case study, the Las Vegas Wash Comprehensive Adaptive Management Plan, illustrates how an adaptive management framework, when its social components come together in a mutually supportive, heuristic way, begins to generate what in collective action is called a platform. The paper further explores how platforms may be more explicitly incorporated into the adaptive management framework to address some of the more persistent social organization difficulties for which adaptive management has been faulted, especially regarding scale issues and the urban context. A revised adaptive management model including a platform is provided, and suggestions made about issues that may be studied using this model.     

The optimal majority with an endogenous status quo

Using the voting procedure proposed by Baron (1996), the consequences are examined of changing the majority required to change legislation. When the majority required is greater than fifty percent, and when voters behave strategically, the first policy proposed (on a stationary equilibrium path) is never defeated subsequently. Which policy gets proposed first depends on which voter gets to make the first proposal. But increasing the required majority induces a mean–preserving spread on the distribution of these policies, if voters' types are distributed symmetrically. Thus before the voting procedure begins, voters would prefer unanimously to see the required majority reduced. I would like to thank an anonymous referee, and an associate editor of this journal, for very helpful comments.     

Segmental dynamic factor analysis for time series of curves

A new approach is introduced in this article for describing and visualizing time series of curves, where each curve has the particularity of being subject to changes in regime. For this purpose, the curves are represented by a regression model including a latent segmentation, and their temporal evolution is modeled through a Gaussian random walk over low-dimensional factors of the regression coefficients. The resulting model is nothing else than a particular state-space model involving discrete and continuous latent variables, whose parameters are estimated across a sequence of curves through a dedicated variational Expectation-Maximization algorithm. The experimental study conducted on simulated data and real time series of curves has shown encouraging results in terms of visualization of their temporal evolution and forecasting.     

LEADERSHIP AND MEMBERSHIP IN THE NUCLEAR FREEZE MOVEMENT:

Participation in social movement activities is distinguished from occupancy of leadership positions in social movement organizations. Two alternative theoretical models derived from the resource mobilization literature, the progression and circulation models, are summarized and their implications regarding participation and leadership are specified. Hypotheses are enumerated for the explanatory factors of individual's self-interest and resources; attitudes, beliefs, and ideology; past organizational experience; background characteristics; and the nature of the association of the individual to the organization. Particular attention is paid to areas where the theoretical models indicate different relationships between the explanatory factors and the outcome variables of participation level and leadership status, and critical tests between the two models are specified. The hypotheses and critical tests are applied to data gathered from a survey of participants in the Cleveland nuclear freeze organization. Self-interest, resource and background characteristics are not found to be associated with either participation level or leadership status. Past experiences and beliefs are important in determining participation levels whereas leadership status is largely explained by the nature of organizational-individual association. The results of the critical testing indicate the circulation model fits the data better than the progression model. The theoretical implications of these findings are discussed and some additional factors helpful in explaining the results are considered.     

Experimental Psychology and Duhem's Problem

Sam S. Rakover, Experimental Psychology and Duhem's Problem, pp. 45–66.
The paper proposes a practical answer to Duhem's problem within the framework of experimental psychology. First, this problem is briefly discussed; second, two studies in psychology are presented illustrating how theories are tested. Thirdly, based on the foregoing, an approach called the "Empirical Reasoning" (ER) is developed and justified. It is shown that the ER approach can successfully cope with Duhem's problem. Finally, the ER approach and the Error Statistics approach of Mayo are critically compared with regard to Duhem's problem.