Economies with a mean demand function

The present paper shows one way to look at G. Debreu and W. Hildenbrand's conjecture that certain atomless economies have mean demand functions. We conclude within the continuity framework that an economy gives rise ‘in general’ to a continuous mean demand function, and that the class of all atomless economies is ‘big’ in the space of all economies with a continuous mean demand function. The same problems are reconsidered within the framework of a space of differentiable preferences at the end.     

Continuous mean demand functions derived from non-convex preferences

In this paper we show that for a large subset of utility functions in the space of all C¹ utility functions and for all prices the mean demand of those consumers whose taste is represented by a given utility function in that subset is uniquely determined. This implies that for a large set of economies mean demand is a continuous function. Our analysis uses derivatives of first and of higher order. The result is essentially a consequence of the multijet transversality theorem.     

Social decision for a measure society

Preference aggregation is here investigated for a society defined as a measure space of individuals and called a measure society. Individual preferences are represented through continuous vnm utilities. It is shown that aggregating preferences in an utilitarian way for any kind of measure society is possible under adapted Pareto conditions.     

When is rational behavior consistent with rules of thumb? a link between evolutionary terminology and neoclassical methodology

In this article, a dynamic industry with optimizing interacting firms is formulated as a Markov game. It is shown that a suitable specification of the state space and the interaction structure leads to constant optimal decisions or routine behavior of all firms. This result depends on two crucial assumptions, the homogeneity of the state space and the linearity of the payoff functions. These assumptions may be interpreted as one possibility to understand bounded rationality. Myopic expectations according to the entry–exit process lead to a similar result in the extended entry–exit model. Hence, neoclassical methods are merged with evolutionary terminology.     

General consumption constraints and regular economies

In the spirit of Smale’s work, we consider pure exchange economies with general consumption sets. In this paper, the consumption set of each household is described in terms of a function called possibility function. The main innovation comes from the dependency of each possibility function with respect to the individual endowments. We prove that, generically in the space of endowments and possibility functions, economies are regular. A regular economy has a finite number of equilibria, which locally depend on endowments and possibility functions in a continuous manner.     

Characterization of optima in smooth Pareto economic systems

Simple techniques of calculus and geometry are used to study and characterize the optima of pure exchange economies in which the utility functions are smooth but not necessarily convex. It is also shown how one can reduce the problem of optimizing p functions on the manifold of states to that of maximizing a single function on a submanifold of this space. Two models are described: one in which a person cannot trade to an optimum unless he starts at one; and one in which a person cannot even get near a local Pareto optimum along continuous ‘trade curves’ from most initial distributions. Finally, the set of optima is described for a generic set of utility mappings.     

On the impatience implications of Paretian social welfare functions

In this paper, we investigate the impatience implications resulting from the assumption of existence of a Paretian social welfare function (SWF) aggregating infinite utility streams. We show, for very general program spaces, that the set of utility streams, at which the SWF exhibits impatience, has the power of the continuum. In the context of a more special program space, which has figured prominently in the literature, we establish that this set is dense, so that even if there is a point in the program space at which the SWF does not exhibit impatience, there are points close to it at which it does. If the Paretian SWF is continuous (in the sup metric), we show that impatience is generic: the collection of points, at which the SWF does not exhibit impatience, is a closed, nowhere dense set.     

Spacing identity: Unfolding social and spatial-material entanglements of identity performance

In this paper, we analyze how architectural design, and the spatial and material changes this involves, contributes to the continuous shaping of identities in an organization. Based upon a case study of organizational and architectural change in a municipal administration at a time of major public sector reforms, we examine how design interventions were used to (re)form work and professional relationships. The paper examines how engagements with spatial arrangements and material artifacts affected people’s sense of both occupational and organizational identity. Taking a relational approach to sociomateriality, the paper contributes to the further theorizing of space in organization studies by proposing the concept of spacing identity to capture the fluidity of identity performance.     

Reprint of: Spacing identity: Unfolding social and spatial-material entanglements of identity performance

In this paper, we analyze how architectural design, and the spatial and material changes this involves, contributes to the continuous shaping of identities in an organization. Based upon a case study of organizational and architectural change in a municipal administration at a time of major public sector reforms, we examine how design interventions were used to (re)form work and professional relationships. The paper examines how engagements with spatial arrangements and material artifacts affected people's sense of both occupational and organizational identity. Taking a relational approach to sociomateriality, the paper contributes to the further theorizing of space in organization studies by proposing the concept of spacing identity to capture the fluidity of identity performance.     

A simple proof of the nonconcavifiability of functions with linear not-all-parallel contour sets

Consider a real-valued function that, on a convex subset of a real vector space, is continuous on line segments and has convex contour sets. Inspired by a compelling intuitive argument due to Aumann (1975), we provide a simple proof that no strictly increasing transformation of such a function can be concave unless all contour sets are parallel, i.e., unless for every pair of contour sets, either their affine hulls are disjoint or one of their affine hulls contains the other.     

大都市连绵区边缘带与核心区的空间关联度研究——以金华市为例

科学判定大都市连绵区与边缘城市之间的空间关联度对准确界定都市连绵带的空间范围具有重要意义,同时对合理地判断都市连绵带的圈层结构也能提供理论依据.长江三角洲是我国目前最大的都市连绵带,由于缺乏空间规模判断的科学方法,学界和决策者在确定空间范围时都是基于经验和行政管理的需要.金华市是长江三角洲重要的边缘城市之一,我们以此为例,通过计算空间关联度的方法确定边缘城市的空间归属.     

Semiparametric estimation of Markov decision processes with continuous state space

We propose a general two-step estimator for a popular Markov discrete choice model that includes a class of Markovian games with continuous observable state space. Our estimation procedure generalizes the computationally attractive methodology of Pesendorfer and Schmidt-Dengler (2008) that assumed finite observable states. This extension is non-trivial as the policy value functions are solutions to some type II integral equations. We show that the inverse problem is well-posed. We provide a set of primitive conditions to ensure root-T consistent estimation for the finite dimensional structural parameters and the distribution theory for the value functions in a time series framework.     

Neighboring information and distributions of agents' characteristics under uncertainty

This paper proposes a topological structure for information. Specifically, information is considered an arbitrary sub-σ-field of the σ-field (of measurable subsets of states of the world) which represents events. A complete metric is defined on the space of all equivalence classes of sub-σ-fields; its uniformity is the same for all probability measures (on the abstract measurable space of states of the world and events) which are uniformly absolutely continuous. With this topology, economic behavior depends continuously on the agent's information; demand functions under uncertainty are jointly continuous in utilities, endowments, and information. Moreover, the value of information is a continuous function of the information sub-σ-field. Technical properties of the topology are also given.     

Modelling security market events in continuous time: Intensity based,multivariate point process models

A continuous time econometric modelling framework for multivariate financial market event (or ‘transactions’) data is developed in which the model is specified via the vector conditional intensity. Generalised Hawkes models are introduced that incorporate inhibitory events and dependence between trading days. Novel omnibus specification tests based on a multivariate random time change theorem are proposed. A bivariate point process model of the timing of trades and mid-quote changes is then presented for a New York Stock Exchange stock and related to the market microstructure literature. The two-way interaction of trades and quote changes in continuous time is found to be important empirically.     

浅析建筑空间形态对舞台空间设计的影响

建筑艺术它顾有空间形态的意义在于为人类提供一个稳定的场所和空间,来容纳连续的行为过程和记忆。舞美作为一门综合艺术,常常需要从建筑的历史中寻取一些布景创作的素材。建筑空间艺术在美学思想、创作方法等方面与舞台设计有许多相似之点。进而发现建筑空间艺术与舞台空间艺术有着一些相同的艺术特性。如果找到在建筑空间艺术上的一些创作方法并把它引用到舞台美术的设计创作中来,对于舞美设计的发展将不无益处。当前舞台美术演出空间分割的创新,已成为舞台美术设计思考的主要课题。     

On the structure of moving average processes

This paper uses Hilbert space methods to develop a rigorous proof that the sum of two uncorrelated moving average processes of order q₁ and q₂ is an MA process of order q ≦ max (q₁, q₂). The methods establish the existence of suitable random shocks for the summed process, they illuminate relationships between the coefficients of such processes and their random shocks, and they provide means for proving that the random shocks of the summed processes are normal when the shocks of the underlying processes are normal. The role of the Wold decomposition is examined in terms of multiple representations of an MA process.     

Project Leadership in Becoming: A Process Study of an Organizational Change Project

Drawing on the current research in general leadership, we propose that a process ontology is relevant and rewarding for project leadership studies. We argue that project leadership can be studied as the ongoing social production of direction through the construction of actors’ space of action, involving continuous construction and reconstruction of (1) past project activities and events; (2) positions and areas of responsibility; (3) discarded, ongoing, and future issues; and (4) intensity, rhythm, and pace. Through an ethnographic case study of an organizational change project, we show how space of action and hence the project direction are in constant flux and becoming.     

Existence of continuous residential land-use equilibria

This paper presents a general result on the existence of competitive equilibria for residential land markets in continuous space. Following standard residential land-use theory, such markets are postulated to involve finitely many types of household continua bidding for land within a continuous finite-dimensional space. In contrast to the standard approach of defining an excess-demand correspondence on a price space, the problem here is reformulated in terms of a ‘population excess-supply correspondence’ on a utility space. This approach allows the analysis to be carried out entirely in terms of finite-dimensional methods, and in particular, allows standard types of fixed-point arguments to be employed.     

Stationary Markov equilibria on a non-compact self-justified set

The existence of stationary processes of temporary equilibria is examined in an OLG model, where there are finitely many commodities and consumers in each period, and endowments profiles and expectations profiles are subject to stochastic shocks. A state space is taken as the set of all payoff-relevant variables, and dynamics of the economy is captured as a stochastic process in the state space. In our model, however, the state space does not necessarily admit a compact-truncation consistent with the intertemporal restrictions because distributions over expectations profiles may have non-compact supports. As shown in Duffie et al. [Duffie, D., Geanakoplos, J., Mas-Colell, A., McLennan, A., 1994. Stationary Markov equilibria. Econometrica 62, 745–781), such a compact-truncation, called a self-justified set, is essential for the existence of stationary Markov equilibria. We extend their existence theorem so as to be applicable to our model.     

辊筒输送机在连续式真空炉中的应用

重力热管自动连续退火除气线是针对太阳能重力热管热处理工艺开发的专用设备,该型设备是一种全自动运行的连续式真空炉。文中介绍了辊筒输送机的类型及其在连续式真空炉设计过程中的选型考虑因素,给出了辊筒输送机在连续式真空炉应用中的选型注意事项。