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1.
2.
The Annual Equal Employment Opportunity Reports and Current Population Survey files are used to examine employment and earnings by race and gender in the telecommunications industry following changes in the industry's affirmative action guidelines and following the divestiture of the American Telephone and Telegraph Company. Nonblack minority men were the only underrepresented group to experience marked employment gains as managers and professional. The relative employment probability of other underrepresented workers remained similar to the levels experienced during the implementation of affirmative action guidelines. Earnings differentials did decline for minority men and white women in the telecommunications industry. However, this finding is only unique to black men as the earnings pattern for white women and nonblack minority men mirror that found for these groups nationally.  相似文献   

3.
Consider a class of power-transformed and threshold GARCH(p,q)(p,q) (PTTGRACH(p,q)(p,q)) model, which is a natural generalization of power-transformed and threshold GARCH(1,1) model in Hwang and Basawa [2004. Stationarity and moment structure for Box–Cox transformed threshold GARCH(1,1) processes. Statistics & Probability Letters 68, 209–220.] and includes the standard GARCH model and many other models as special cases. We first establish the asymptotic normality for quasi-maximum likelihood estimators (QMLE) of the parameters under the condition that the error distribution has finite fourth moment. For the case of heavy-tailed errors, we propose a least absolute deviations estimation (LADE) for PTTGARCH(p,q)(p,q) model, and prove that the LADE is asymptotically normally distributed under very weak moment conditions. This paves the way for a statistical inference based on asymptotic normality for heavy-tailed PTTGARCH(p,q)(p,q) models. As a consequence, we can construct the Wald test for GARCH structure and discuss the order selection problem in heavy-tailed cases. Numerical results show that LADE is more accurate than QMLE for heavy-tailed errors. Furthermore, the theory is applied to the daily returns of the Hong Kong Hang Seng Index, which suggests that asymmetry and nonlinearity could be present in the financial time series and the PTTGARCH model is capable of capturing these characteristics. As for the probabilistic structure of PTTGARCH(p,q)(p,q) model, we give in the appendix a necessary and sufficient condition for the existence of a strictly stationary solution of the model, the existence of the moments and the tail behavior of the strictly stationary solution.  相似文献   

4.
H. S. Konijn 《Metrika》1981,28(1):109-121
Summary On the basis of a simple random sample from a population, on which a cross-classification is defined with known marginal frequenciesN i. andN .j , one wishes to estimate the cell frequenciesN ij , as well as cell totalsY ij , marginal totalsY i. andY .j , and the grand totalY for characteristics measured on the units. Various authors have discussed so-called raking ratio estimators, which are built up from the estimated cell values by addition. They have given the bias and variance of this estimator ofY. This paper derives biases, variances and covariances for the corresponding estimators of the cell and marginal totals and of the corresponding marginal averages.  相似文献   

5.
Women’s poverty rates are higher than men’s, with single mothers having extremely high poverty rates. This article first briefly examines poverty measures and U.S. poverty rates among men and women. The author then describes and evaluates three categories of economic research on poverty: the lack or inadequacy of employment and earnings; family structure and welfare; and earnings capacities, care-giving responsibilities and employment. Finally the author assesses the policies to alleviate women’s poverty derived from these explanations.  相似文献   

6.
Book reviewed in this article: Gottdiener, M. 1977: Planned sprawl: private and public interests in suburbia. Lineberry, R. L. 1977: Equality and urban policy: the distribution of municipal public services. Abrams, P. and Wrigley, E. A. , editors, 1978: Towns in societies: essays in economic history and historical sociology. Beirne, P. 1977: Fair rent and legal fiction. Holloway, J. and Picciotto, S. , editors, 1978: State and capital: a marxist debate. Léveillée, J. 1978: Dévelopment urbain et politiques gouvernementales urbaines dans l'agglomération montréalaise Long, N. 1977: An introduction to the sociology of rural development. Massey, D. and Catalano, A. 1978: Capital and land: landownership by capital in Great Britain. Pretecille, E. 1974: Jeux, modèles et simulations: critique des jeux urbains. Redclift, M. R. 1978: Agrarian reform and peasant organization on the Ecuadorian Coast. Sussman, C. , editor, 1976: Planning the Fourth Migration: the neglected vision of the Regional Planning Association of America. Vance, J. A. 1977: This scene of man: the role and structure of the city in the geography of western civilisation. Wirth, J. D. and Jones, R. L. , editors, 1978: Manchester and São Paulo: problems of rapid urban growth. Young, K. and Kramer, J. 1978: Strategy and conflict in metropolitan housing—suburbia versus the Greater London Council 1965–75.  相似文献   

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8.
Whilst consumption has frequently been associated with the postmodern city, insufficient regard has been paid to the systemic logic of consumption. It is argued here that consumption takes on an increasingly significant role in this respect. Specifically, we have been witness to a profound social transformation whereby the active repression once centred on the city as a locus of production has given way to a new mode of social integration, which accords to the logic of seduction. By tracing the development of the modern city in terms of the imposition of the law and its transgression — figured in terms of cognitive space and the ‘spectral presence’ of the stranger — the significance of the postmodern is theorized in terms of the systemic appropriation of an aesthetic space initially traced out by the flâneur. The ludic existence of the flâneur has thus been translated into the general condition of a society oriented around consumption. This condition implies a new form of cybernetic control, governed by the aleatory play of the code, rather than the direct surveillance characteristic of the modern city. As a consequence, urban space has itself undergone a transition, which we might begin to address in terms of a ‘posturban’ hyperspace.  相似文献   

9.
Abstract . Reflexive predictions are self-defeating or self-fulfilling. However, it was shown that in most cases of self defeating public predictions of social events conceptually at least one correct prediction exists. Unfortunately the term “reflexive prediction” is applied in the literature to quite distinct phenomena. A. Grünbaum, moreover, argued that reflexive prediction occurs also in the natural sciences using as example the fire-control system which “obeys only natural laws.” The purpose of this paper is two fold: first, it clarifies the terminological confusion. Second, it argues that every man-made tool (fire-control systems are tools) obeys natural laws and so does the person. The question of a person's higher functions, such as expectation and decision is only acknowledged. The conclusions are (1) that there is a fundamental difference between reaction to public (predictive) utterances and reaction to discriminatory behavior based on private ptediciion. (2) The reflexivity of public prediction is a phenomenon characteristic of the social sciences. at least as long as these disciplines are set apart from the natural sciences.  相似文献   

10.
We investigate the relation between abnormal research and development (R&D) investments change and expected stock returns. We provide evidence that firms that abnormally increase their R&D investments (RDI) earn higher returns in comparison to the market portfolio. Specifically, our findings document an economically significant annual positive abnormal RDI returns that ranges from 3.2% to 11.5%. These findings are robust to well-established risk factors in the literature and suggest that the abnormal increases in RDI impacts stock returns.  相似文献   

11.
Both notions elaborated in this article, exclusion and the border, are cultural constructs which can take on different meanings in different milieux. In order to understand socio‐cultural exclusion in the context of EU integration and new centralities created by globalization, the project presented here addressed social, cultural and spatial exclusion in peripheral EU border cities and islands. This article focuses on how borderland residents experience socio‐cultural exclusion of ‘others’ and of themselves, and forge their spatialities and mappings. It makes distinctions on several levels: geographically, between external and internal EU borders, between ‘transborder’ and ‘bounded’ field sites and between variations of spatialities and mappings; culturally, between boundary gateways and walls, and between socio‐cultural and spatial exclusion, isolation and insularity; anthropologically, between social and cultural markers dividing the subject and the ‘other’. Local experiences and spatialities along the border were found to be complex and often in conflict with dominant definitions and preconceptions. This, along with the multiple levels of exclusion and difference found on the EU border, has implications for research priorities and policy restructuring. Les deux notions détaillées dans cet article, exclusion et frontière, sont des concepts culturels qui peuvent prendre un sens différent en fonction du milieu. Afin d’appréhender l’exclusion socioculturelle dans le cadre de l’intégration européenne et des nouvelles centralités créées par la mondialisation, le projet traite l’exclusion sociale, culturelle et spatiale dans les villes et îles situées à la périphérie de l’UE. Il s’attache à la façon dont les résidents frontaliers vivent une exclusion socioculturelle des ‘autres’ et d’eux‐mêmes, tout en établissant leurs spatialités et leurs cartographies. Plusieurs plans sont identifiés: un plan géographique, entre frontières internes et externes de l’UE, entre sites ‘transfrontaliers’ et territoires ‘délimités’, et entre divergences de spatialités et de cartographies; un plan culturel, entre accès et remparts frontaliers, et entre insularité, isolement et exclusion socioculturels et spatiaux; un plan anthropologique, entre les repères sociaux et culturels qui séparent le sujet de ‘l’autre’. Le long de la frontière, spatialités et expériences locales se sont révélées complexes et souvent en opposition avec les définitions et a priori dominants. Cet aspect, allié aux multiples niveaux d’exclusion et de différence découverts sur la frontière européenne, influence les priorités de recherches et la restructuration des politiques.  相似文献   

12.
This paper deals with the issue of arbitrage with differential information and incomplete financial markets, with a focus on information that no-arbitrage asset prices can reveal. Time and uncertainty are represented by two periods and a finite set S of states of nature, one of which will prevail at the second period. Agents may operate limited financial transfers across periods and states via finitely many nominal assets. Each agent i has a private information about which state will prevail at the second period; this information is represented by a subset Si of S. Agents receive no wrong information in the sense that the “true state” belongs to the “pooled information” set ∩iSi, hence assumed to be non-empty.Our analysis is two-fold. We first extend the classical symmetric information analysis to the asymmetric setting, via a concept of no-arbitrage price. Second, we study how such no-arbitrage prices convey information to agents in a decentralized way. The main difference between the symmetric and the asymmetric settings stems from the fact that a classical no-arbitrage asset price (common to every agent) always exists in the first case, but no longer in the asymmetric one, thus allowing arbitrage opportunities. This is the main reason why agents may need to refine their information up to an information structure which precludes arbitrage.  相似文献   

13.
In the Uptown area of Chicago and Sheffield, England’s Sharrow neighborhood, redevelopment initiatives in the late 1960s and early 1970s produced a significant degree of community conflict. Throughout the 1970s and 1980s a variety of grassroots movements appeared in each community. The legacy of redevelopment-derived conflict and community-based organizing in the two communities suggests that there is more variation in neighborhood grassroots politics — even in communities with comparable public policy and organizing histories — than prevailing explanations of neighborhood mobilization tend to acknowledge. However, with the 1990s a convergence in the Uptown and Sharrow experiences has appeared: the narrowing of their grassroots organizations’ political agendas, which can be attributed to national shifts in political discourse and public policy. Dans le quartier de Uptown à Chicago et le quartier de Sharrow à Sheffield en Angleterre, les initiatives de redéveloppement à la fin des années soixante et le début des années soixante-dix ont causé un degré significatif de conflit dans la communauté. Durant les années soixante-dix et quatre-vingt divers mouvements populaires sont apparus dans ces communautés. Dans les deux communautés, le résultat des conflits dûs au redéveloppement et de l'organisation basée dans la communauté suggère qu'il y a plus de variation dans les politiques populaires des quartiers — même dans les communautés qui ont des politiques publiques et un passé d'organisation similaires — que les explications dominantes de la mobilisation de quartier tendent à reconna^tre. Cependant, dans les années quatre-vingt-dix, une convergence entre les expériences de Uptown et Sharrow est apparue: le rétrécissement des programmes politiques de leurs organisations populaires qui peut être attribué aux changements nationaux du discours politique et de la politique publique.  相似文献   

14.
The aim of this article is to define what is meant by clusters, their characteristics or determinants and the advantages they generate, focusing on the role they play in boosting entrepreneurship and new venture creation. In clusters, a balance is reached between cooperation and competition which becomes evident in the higher productivity of the companies because of their increased access to inputs, information, technology and institutions; or in greater innovation and venture creation. The cluster incentivizes the entry of new companies or start-ups. The hope is, then, that the new companies will revitalize specific regions where competitiveness has fallen and that entrepreneurship will contribute to economic development and improved country-wide competitiveness.
ángeles Montoro-Sánchez (Corresponding author)Email:
  相似文献   

15.
E-Leadership and Virtual Teams   总被引:1,自引:0,他引:1  
In this paper we have identified some key challenges for E-leaders of virtual teams. Among the most salient of these are the following:
• The difficulty of keeping tight and loose controls on intermediate progress toward goals
• Promoting close cooperation among teams and team members in order to integrate deliverables
• Encouraging and recognizing emergent leaders in virtual teams
• Establishing explicit processes for archiving important written documentation
• Establishing and maintaining norms and procedures early in a team’s formation and development
• Establishing proper boundaries between home and work
Virtual team environments magnify the differences between good and bad projects, organizations, teams, and leaders. The nature of such projects is that there is little tolerance for ineffective leadership. There are some specific issues and techniques for mitigating the negative effects of more dispersed employees, but these are merely extensions of good leadership—they cannot make up for the lack of it.

SELECTED BIBLIOGRAPHY

An excellent reference for research on teams is M. E. Shaw, R. M. McIntyre, and E. Salas, “Measuring and Managing for Team Performance: Emerging Principles from Complex Environments,” in R. A. Guzzo and E. Salas, eds., Team Effectiveness and Decision Making in Organizations (San Francisco: Jossey-Bass, 1995). For a fuller discussion of teleworking and performance-management issues in virtual teams, see W. F. Cascio, “Managing a Virtual Workplace,” Academy of Management Executive, 2000, 14(3), 81–90, and also C. Joinson, “Managing Virtual Teams,” HRMagazine, June 2002, 69–73. Several sources discuss the issue of trust in virtual teams: D. Coutu, “Trust in Virtual Teams,” Harvard Business Review, May–June 1998, 20–21; S. L. Jarvenpaa, K. Knoll, and D. E. Leidner, “Is Anybody Out There? Antecedents of Trust in Global Virtual Teams,” Journal of Management Information Systems, 1998, 14(4), 29–64. See also Knoll and Jarvenpaa, “Working Together in Global Virtual Teams,” in M. Igbaria and M. Tan, eds., The Virtual Workplace (Hershey, PA: Idea Group Publishing, 1998).Estimates of the number of teleworkers vary. For examples, see Gartner Group, Report R-06-6639, November 18, 1998, and also Telework America survey, news release, October 23, 2001. We learned about CPP’s approach to managing virtual work arrangements through David Krantz, personal communication, August 20, 2002, Palo Alto, CA.There are several excellent references on emergent leaders. For example, see G. Lumsden and D. Lumsden, Communicating in Groups and Teams: Sharing Leadership (Belmont, CA: Wadsworth, 1993); Lumsden and Lumsden, Groups: Theory and Experience, 4th ed. (Boston: Houghton, 1993); R. W. Napier and M. K. Gershenfeld, Groups: Theory and Experience, 4th ed. (Boston: Houghton, 1989); and M. E. Shaw, Group Dynamics: The Psychology of Small Group Behavior, 3rd ed. (New York: McGraw-Hill, 1981).An excellent source for e-mail style is D. Angell and B. Heslop, The Elements of E-mail Style: Communicate Effectively via Electronic Mail (Reading, MA: Addison-Wesley Publishing Company, 1994). To read more on the growing demand for flexible work arrangements, see “The New World of Work: Flexibility is the Watchword,” Business Week, 10 January 2000, 36.For more on individualism and collectivism, see H. C. Triandis, “Cross-cultural Industrial and Organizational Psychology,” in H. C. Triandis, M. D. Dunnette, and L. M. Hough, eds., Handbook of Industrial and Organizational Psychology, 2nd ed., vol. 4 (Palo Alto, CA: Consulting Psychologists Press, 1994, 103–172).Executive SummaryAs the wired world brings us all closer together, at the same time as we are separated by time and distance, leadership in virtual teams becomes ever more important. Information technology makes it possible to build far-flung networks of organizational contributors, although unique leadership challenges accompany their formation and operation. This paper describes the growth of virtual teams, the various forms they assume, the kinds of information and support they need to function effectively, and the leadership challenges inherent in each form. We then provide workable, practical solutions to each of the leadership challenges identified.  相似文献   

16.
The concept of causality introduced by Wiener [Wiener, N., 1956. The theory of prediction, In: E.F. Beckenback, ed., The Theory of Prediction, McGraw-Hill, New York (Chapter 8)] and Granger [Granger, C. W.J., 1969. Investigating causal relations by econometric models and cross-spectral methods, Econometrica 37, 424–459] is defined in terms of predictability one period ahead. This concept can be generalized by considering causality at any given horizon hh as well as tests for the corresponding non-causality [Dufour, J.-M., Renault, E., 1998. Short-run and long-run causality in time series: Theory. Econometrica 66, 1099–1125; Dufour, J.-M., Pelletier, D., Renault, É., 2006. Short run and long run causality in time series: Inference, Journal of Econometrics 132 (2), 337–362]. Instead of tests for non-causality at a given horizon, we study the problem of measuring causality between two vector processes. Existing causality measures have been defined only for the horizon 1, and they fail to capture indirect causality. We propose generalizations to any horizon hh of the measures introduced by Geweke [Geweke, J., 1982. Measurement of linear dependence and feedback between multiple time series. Journal of the American Statistical Association 77, 304–313]. Nonparametric and parametric measures of unidirectional causality and instantaneous effects are considered. On noting that the causality measures typically involve complex functions of model parameters in VAR and VARMA models, we propose a simple simulation-based method to evaluate these measures for any VARMA model. We also describe asymptotically valid nonparametric confidence intervals, based on a bootstrap technique. Finally, the proposed measures are applied to study causality relations at different horizons between macroeconomic, monetary and financial variables in the US.  相似文献   

17.
Abstract . Henry George's land reform ideas became known in Germany not through his writing or speaking but through the efforts of Michael Flürscheim, an industrialist and pioneer social reformer, who first presented those ideas to the public. The American's idea that the land value tax was the only legitimate source of government revenue as the only economic surplus had found no acceptance among German socialist leaders. It was a capitalist, Flürscheim, who was inspired by George's theories and wrote and spoke about them. Flürscheim brought about the foundation of the first German land reform organization. Though it failed, a successor became the largest such association in the world.  相似文献   

18.
This paper reports the results of a meta-analytic review of the relationship between person and task-focused leader behaviors, on the one hand, and team performance, on the other hand. The results, based on 89 independent samples, show a moderate positive (ρ = 0.33) association between both types of leadership behaviors and subjective team performance. For objective team performance, the effect sizes are smaller, yet positive (ρ = 0.19 for task-focused leadership behaviors and ρ = 0.18 for person-focused leadership behaviors). Furthermore, with respect to the methodological moderators, the analyses show that the relationships were stronger when leadership behaviors were rated by the leaders themselves, rather than by others, and the association was stronger when the correlations were estimated at the individual level, as opposed to the team level of analysis. Concerning conceptual moderators, team type was identified as a significant moderator, and correlations between a person-focused leadership behavior and team performance were stronger for service and project teams than for action/performing teams. Task interdependence was another moderator tested in our meta-analysis, yet our results show no clear moderating effect of task interdependence on the relationship between leadership behavior and team performance.  相似文献   

19.
This paper has attempted to clarify some weaknesses and flaws contained in Miller and Jensen's analysis. In particular, we have demonstrated that in Miller and Jensen's model, if the production function is homogeneous of degree one and the transport rate functions are independent of quantities shipped, it is impossible to have an interior solution. In addition, we have evaluated the role of the generalized transport rate functions in the profit-maximization location model with and without a prescribed level of output and shown that if transport rates depend on quantities shipped and have constant elasticities, then a linearly homogeneous production function is not sufficient to insure that optimum location is independent of output or the demand function. This result clearly invalidates Miller and Jensen's assertion.  相似文献   

20.
We employ the original Card and Krueger (American Economic Review 1994; 84: 772–793) and Neumark and Wascher (American Economic Review 2000; 90: 1362–1396) data together with the changes‐in‐changes estimator to re‐examine the evidence for the effect of minimum wages on employment. Our study reconciles the controversial positive average employment effect reported by the former study and the negative average employment effect reported by the latter study. Our main finding, which is supported by both datasets, is that the controversial result remains valid only for small fast‐food restaurants. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

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