房地产销售商投机行为的稳定性分析

分析了房地产销售的纳什博弈模型、房地产开发商作为领导者寡头博弈模型、房地产销售商作为领导者寡头博弈模型、房地产市场销售讨价还价博弈模型四种房地产市场销售博弈模型的利益分配机制和收益策略.结果表明,在房地产开发商作为领导者寡头博弈策略中,房地产销售商具有实施投机行为的动机,利益分配机制不稳定;在房地产销售商作为领导者寡头博弈策略中,房地产销售商没有实施投机行为的动机,利益分配机制的稳定;在房地产市场销售讨价还价博弈策略中,房地产销售商利益分配机制的稳定性与房地产产品的差异化替代率和无限期重复博弈策略的贴现率均有关.     

p -SOLVABILITY AND A GENERALIZATION OF PRIME GRAPHS OF FINITE GROUPS

Abstract

The real Torelli mapping, from the moduli space of real curves of genus g to the moduli space of g-dimensional real principally polarized abelian varieties, sends a real curve into its real Jacobian. The real Schottky problem is to describe its image. The results contained in the present paper concern hyperelliptic real curves and in particular real curves of genus 2. We exhibit also some counterexamples for the non-hyperelliptic case.     

关于严实Hilbert环

在本文中，严实Ｈｉｌｂｅｒｔ环得到了更进一步的刻划．本文的主要结果是：一个环Ａ是严实Ｈｉｌｂｅｒｔ环，当且仅当多项式环Ａ［Ｘ］的每个实极大理想在Ａ上的局限是Ａ的一个极大理想，当且仅当Ａ是实Ｈｉｌｂｅｒｔ环，且Ａ［Ｘ］的每个实极大理想是极大的．     

Real perturbation values and real quadratic forms in a complex vector space

A sequence of real numbers connected to a complex matrix is introduced. It is shown how these real perturbation values can be computed and that they have several properties similar to the singular values. The so-called real pseudospectra and real stability radii can be computed using the real perturbation values. The main result concerns the signature of real quadratic forms in complex vector spaces.     

关于实Hilbert环

通过引进“强实Hilbert环”这一概念,本文证明了,一个环A是强实Hilbert环,当且仅当多项式环A[X]是实Hilbert环,当且仅当A[X]的每个实极大理想在A上的局限是实极大的,从而文献[1]中两个主要结果被否定.此外,本文还研究了所谓的“严格的实Hilbert环”,这类环对于半代数零点定理等方面的探讨更具应用意义.     

关于严实Hilbert环

在本文中，严实Ｈｉｌｂｅｒｔ环得到了更进一步的刻划．本文的主要结果是：一个环Ａ是严实Ｈｉｌｂｅｒｔ环，当且仅当多项式环Ａ［Ｘ］的每个实极大理想在Ａ上的局限是Ａ的一个极大理想，当且仅当Ａ是实Ｈｉｌｂｅｒｔ环，且Ａ［Ｘ］的每个实极大理想是极大的．     

Real Closed Valuation Rings

The real closed valuation rings, i.e., convex subrings of real closed fields, form a proper subclass of the class of real closed domains. It is shown how one can recognize whether a real closed domain is a valuation ring. This leads to a characterization of the totally ordered domains whose real closure is a valuation ring. Real closures of totally ordered factor rings of coordinate rings of real algebraic varieties are very frequently valuation rings. In particular, the real closure of the coordinate ring of a curve is an SV-ring (i.e., the factor rings modulo prime ideals are valuation rings). Real closed valuation rings play a role in the definition of real closed rings, as well as in the construction of real closures of rings and porings. They can also be used for the study of univariate differentiable semi-algebraic functions. This leads to the notion of differentiablility of semi-algebraic functions along half branches of curves.     

Existence of real eigenvalues of real tensors

We use the Brouwer degree to establish the existence of real eigenpairs of higher order real tensors in various settings. Also, we provide some finer criteria for the existence of real eigenpairs of two-dimensional real tensors and give a complete classification of the Brouwer degree zero and ±2 maps induced by general third order two-dimensional real tensors.     

Error bounds in the gap metric for dissipative balanced approximations

We derive an error bound in the gap metric for positive real balanced truncation and positive real singular perturbation approximation. We prove these results by working in the context of dissipative driving-variable systems, as in behavioral and state/signal systems theory. In such a framework no prior distinction is made between inputs and outputs. Dissipativity preserving balanced truncation of dissipative driving-variable systems is addressed and a gap metric error bound is obtained. Bounded real and positive real input–state–output systems are manifestations of a dissipative driving-variable system through particular decompositions of the signal space. Under such decompositions the existing bounded real and positive real balanced truncation schemes can be seen as special cases of dissipative balanced truncation and the new positive real error bounds follow.     

交换的实W~*-代数

本文指出，交换的（复）Ｗ 代数的大部分结果对于实情形仍然成立，自然有周期为２同胚的差别．此外，不同于复情形，可分实Ｈｉｌｂｅｒｔ空间中不包含任何极小投影的交换实ＶＮ代数同构于Ｌ∞（［０，１］），Ｌ∞ｒ（［０，１］）或Ｌ∞（［０，１］）Ｌ∞ｒ（［０，１］）．     

On Real Simple Left-symmetric Algebras

In this article, we commence to study the real (simple) left-symmetric algebras. From the known classification of certain complex (semi)simple left-symmetric algebras, we classify their corresponding real forms. We not only obtain the classification of real simple left-symmetric algebras in low dimensions, but also find certain examples of real simple left-symmetric algebras in higher dimensions. In particular, there exists a complex simple left-symmetric algebra without any real form. We also give a geometric construction for a class of real simple left-symmetric algebras. At last, we apply the classification results to study some structures related to geometry.     

基于MIV-BP型网络实验的房地产项目风险识别研究

为了更准确更客观地识别房地产项目中的风险,为房地产项目投资决策提供科学依据和参考,有效地规避风险,本研究在BP神经网络 (Back-Propagation Neural Network)建模的基础上,采取MIV(Mean Impact Value)算法对BP神经网络模型进行变量筛选的网络优化和改良,从而形成新的优化后的MIV-BP(Mean Impact Value Back-Propagation Neural Network)神经网络,并以此用于评价房地产项目中的风险度以及各因素在风险度中的影响作用大小;同时选取目前相关的房地产项目数据进行仿真实证分析和验证。验证实验结果表明,MIV-BP型神经网络对于房地产项目风险度识别具有良好的适应性和准确性,实验结果客观,达到专家评价的要求,并在风险因素作用度分析上具有良好的应用价值。     

Sensitivity measures for equity investments

By differentiating a discounted cash flow valuation formula(expressed in real terms), with respect to the underlying fundamentalreal variables, we derive ‘sensitivity measures’for equity investments. These show how the present value ofexpected future dividends will vary as the real discount ratechanges and the long-term real dividend growth rate changes.In both cases, sensitivity depends on dividend yield: the lowerthe dividend yield, the more sensitive the stock to changesin both the real discount rate and the real growth rate. Wealso derive a total differential model which allows for simultaneouschanges in both the real discount rate and the real growth rate,and briefly compare this model with the model of Leibowitz etal. for equity duration.     

图灵机计算实数函数的稳定性

定义在全体实数上的可计算函数是一个很重要的概念．在这以前定义可计算的实数函数有两个途径．第一个途径是首先要定义可计算实数的指标．想要确定实数函数y=f（x）是不是可以计算就要看是否存在一个自然数的（部分）递归函数将可计算实数x的指标对应到可计算实数y的指标．这样一来对实数函数的研究依赖于对自然数函数的研究．第二个定义可计算的实数函数的途径是以逼近为基础的．一个实数函数是可以计算的如果它既是序列可计算的同时也是一致连续的．用这个途径来定义可计算实数函数使用的条件过强以至于很多有用的实数函数成为不可计算的实数函数．例如“〈”和“=”的命题函数就是不可以计算的因为它们是不连续的命题函数．本文讨论了图灵机的稳定性并且给出了一个基于稳定图灵机的可计算实数函数的定义．我们的定义不需要用到自然数的（部分）递归函数．根据我们的定义很多常用实数函数特别是一些不连续的常用实数函数都是可以计算的．用我们的定义来讨论可计算实数函数的性质比原来的定义要方便得多．     

On the probability distribution of data at points in real complete intersection varieties

We show several estimates on the probability distribution of some data at points in real complete intersection varieties: norms of real affine solutions, condition number of real solution of real systems of multi-variate polynomial equations and convergence radius of Newton's operator for under-determined system of multi-variate polynomial equations.     

The impact of investment lags on investment decision

This paper suggests a valuation framework for an investment project through the concept of real options. Generally, in real asset world, decision time and its payment time are not identical. This so-called investment lag problem should be considered when valuing real assets. When investment lags exist, firms’ accommodation capacities play important roles. In this paper, the real effect of investment lag on investment value is tested upon various conditions. We show the valuation process of real assets under the risk-neutral world. The closed-form formula is also provided for valuing real assets, including R&D project.     

The Space of Unordered Real Line Arrangements

The set of all unordered real line arrangements of given degree in the real projective plane is known to have a natural semialgebraic structure. The nonreduced arrangements are singular points of this structure. We show that the set of all unordered real line arrangements of given degree also has a natural structure of a smooth compact connected affine real algebraic variety. In fact, as such, it is isomorphic to a real projective space. As a consequence, we get a projectively linear structure on the set of all real line arrangements of given degree. We also show that the universal family of unordered real line arrangements of given degree is not algebraic.     

《实变函数论》中一个定理的初等证明——课程教学改革初探

利用有限覆盖定理给出了一个命题的初等证明,而《实变函数论》中的一个重要定理可作为该命题的一个直接推论.由此展现作为基础的实数完备性在实分析中的重要地位,也为《实变函数论》课程的部分内容的教学改革提供一种值得探讨的新思路.     

基于PCA-VAR模型的房地产信贷政策调控效应分析

有效的房地产调控,既要实现稳定房价、控制房地产开发投资过快增长等调控目标,同时也不会对宏观经济带来过大的负面影响.在分析各类房地产调控政策传导机制的基础上,通过构建PCA-VAR模型,并综合运用了协整分析、Granger因果检验、方差分解和脉冲效应分析等方法,细致测算了房地产信贷政策对房地产市场和宏观经济的影响,据此为我国实施房地产调控提供政策建议.     

关于三元r-循环实矩阵及其应用

讨论三元 r-循环实矩阵 ,给出了三元 r-循环实矩阵的行列式和逆矩阵的实表达式 .从而得到r-循环实矩阵的行列式和逆矩阵的实表达式