Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Alfred P. Sloan School of Management. / Vita. / Bibliography: leaves 257-265. / Ph.D.

Li Zimu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 65-68). / Abstracts in English and Chinese. / Abstract --- p.ii / 中文摘要 --- p.iii / Acknowledgements --- p.iv / Contents --- p.v / Chapter Chapter 1. --- Introduction --- p.1 / Chapter Chapter 2. --- Literature Review --- p.5 / Chapter 2.1 --- Duration Dependence in Business Cycles --- p.5 / Chapter 2.2 --- Duration Dependence in Stock Market Cycles --- p.7 / Chapter 2.3 --- Definition of Bull and Bear Markets --- p.10 / Chapter Chapter 3. --- Nonparametric Tests for Duration Dependence --- p.12 / Chapter 3.1 --- Duration Dependence --- p.12 / Chapter 3.2 --- Stock Market Cycle Periodicity --- p.15 / Chapter 3.3 --- W and W (t0 =a) Tests --- p.18 / Chapter 3.4 --- Z and Z (t0 =a) Tests --- p.20 / Chapter Chapter 4. --- Data Analysis --- p.21 / Chapter 4.1 --- Dow Jones Industrial Average Index --- p.23 / Chapter 4.2 --- NASDAQ Composite Index --- p.29 / Chapter 4.3 --- Shanghai A Share Index --- p.33 / Chapter 4.4 --- Shenzhen B Share Index --- p.38 / Chapter Chapter 5. --- Empirical Results --- p.42 / Chapter 5.1 --- Dow Jones Industrial Average Index --- p.45 / Chapter 5.2 --- NASDAQ Composite Index --- p.47 / Chapter 5.3 --- Shanghai A Share Index --- p.49 / Chapter 5.4 --- Shenzhen B Share Index --- p.51 / Chapter 5.5 --- Summary of Significant W and Z tests --- p.53 / Chapter Chapter 6. --- Sub-sample Analysis --- p.54 / Chapter 6.1 --- Sub-sample 1 of the Dow Jones Index´ؤ --- p.56 / Chapter 6.2 --- Sub-sample 2 of the Dow Jones Index´ؤ --- p.57 / Chapter 6.3 --- Comparison of Sub-samples of the Dow Jones Index --- p.58 / Chapter 6.4 --- Comparison of the Dow Jones Index and the NASDAQ Composite Index --- p.60 / Chapter Chapter 7. --- Conclusion --- p.62 / References --- p.65

Time-series data that reflect a periodic pattern are often used in psychology. In personality psychology, Brown and Moskowitz (1998) used spectral analysis to study whether fluctuations in the expression of four interpersonal behaviors show a cyclical pattern. Spline smoothing had also been used in the past to track the non-periodic trend, but no research has yet been done that combines spectral analysis and spline smoothing. The present thesis describes a new model which combines these two techniques to capture both periodic and non-periodic trends in the data. / The new model is then applied to Brown and Moskowitz's time-series data to investigate the long-term evolution to the four interpersonal behaviors, and to the GDP data to examine the periodic and non-periodic pattern for the GDP values of the 16 countries. Finally, the extent to which the model is accurate is tested using simulated data.

[Truncated abstract] Estimating internal biogeochemical fluxes is essential to the understanding of the dynamic of aquatic ecosystems. Different ecological approaches have been used to gain insight into the internal cycling, but success has been limited. A critical point is the identification of the characteristic scales of patterns and the underlying processes affecting the behaviour of biological and chemical species. Failing to capture these scales leads to misinterpretation of field and numerical data. In this study, key aspects in the design of ecological surveys are identified to ensure that the internal biogeochemical processes are well represented. In the first part of this thesis, a 1D reaction-diffusion-advection equation is used to investigate the formation of patterns and relevant time and spatial scales. This is used to define an approach for the determination of a critical domain size that allows differentiation of the role of local and internal cycling from advective fluxes across the open boundaries in a shallow coastal ecosystem. By using a 3D numerical model, in conjunction with an extensive field data set, it is shown that domain sizes must be larger than this critical value in order to capture the patterns generated within the system. For smaller domains, transport processes control the evolution of the system across the boundaries misleading the interpretation of the internal ecological dynamics. The study of the influence of boundary fluxes on ecological patchiness was motivated by the need to define the size of the domain necessary for the assessment of the impact of a sewage outflow on a coastal regime. The quantification of biogeochemical processes has proven to be difficult to achieve especially under conditions of high spatial and temporal hydrodynamic and biogeochemical variability. In the second part of this thesis, a Lagrangian experimental design is employed to estimate biogeochemical rate coefficients in situ. A set of four drogues and a cross-transect sampling design is used to capture the patchy distribution of phytoplankton and nutrient species, and high transport and mixing rates. ... Total chlorophyll from both models shows similar behavior when the variability in the 3D model, expressed as Chlamax/Chlamin, is low. When Chlamax/Chlamin is high, the difference between the biomass predicted by the two models reaches 30% due to the generation of localised patches. Comparison of the 1D and 3D results highlights the need of using models that are able to resolve the spatial complexity to some extent, as the use of averaged properties may produce misleading results. This is especially important in the presence of patches with differential physiological and biogeochemical characteristics, and nonlinear processes, in which case biomass average is not necessarily linearly related to the averaged environment.

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In the second essay, we analyze the possibility of generating indeterminacy in the monetary models with nominal rigidities under increasing returns to scale technology. We find that in the monetary models with flexible wage (prices can be either flexible or staggered), the minimum degree of returns to scale necessary for local indeterminacy is inversely related to the magnitude of the labor-supply elasticity. This result is consistent with the one obtained in a real model in Benhabib and Farmer (1994), in particular, indeterminacy can only occur under very large labor-supply elasticity. Furthermore, we show that when incorporating nominal wage rigidities, indeterminacy can occur under an empirically plausible labor supply elasticity. However, the role of nominal rigidities for indeterminacy is very sensitive to the degree of capital adjustment costs, but it is robust to the assumptions of timing and the degrees of nominal rigidities. / The first essay discusses about indeterminacy under interest rate policy. We show that, with endogenous investment, virtually all monetary policy rules that set a nominal interest rate in response solely to expected future inflation induce real indeterminacy in models with (i) staggered prices, (ii) staggered prices and staggered wages, and (iii) staggered prices, staggered wages, and firm-specific capital. In (i), policy's response to current output can help significantly in ensuring determinacy with an infinite labor supply elasticity, but little with empirically plausible labor supply elasticity. In (ii), responding to output always helps a great deal, though under low price stickiness and without capital adjustment cost it may call for a moderate response to output in order to ensure determinacy for a wide range of response to inflation. In (iii), even a tiny response to output can always render equilibrium determinate for a wide range of response to inflation. We also find that the policy's response to lagged interest rate further enhances macroeconomic stability, though in many cases some response to output is still essential for ensuring a nonempty determinacy region, and even in the other cases responding to output often remains important in order to ensure determinacy for a wide range of response to inflation. Our results are quantitatively invariant to the presence of habit persistence in consumption. / The third essay studies the stability puzzle (Evans and McGough, 2002): why does indeterminacy almost always imply expectational unstability in RBC models? Following Meng and Yip (2008), we relax the restrictions on the magnitude of capital externalities with Cobb-Douglas technology. We find regions for joint indeterminacy and E-stability (i) when the felicity function is separable in consumption and leisure and there are negative capital externalities; or (ii) when the felicity function is non-separable and the social elasticity of production with respect to capital exceeds one. We further show that with the general utility function, a necessary condition for joint indeterminacy and E-stability is that the labor-demand curve is upward-sloping and steeper than the Frisch labor-supply curve. / This thesis consists of three essays on the issues of monetary policy, indeterminacy and expectational stability (E-stability). / Xue, Jianpo. / Adviser: Qinglai Meng. / Source: Dissertation Abstracts International, Volume: 70-06, Section: A, page: 2178. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest dissertations and theses, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

The present work uses statistical mechanics tools to investigate the dynamics of markets, prices, trades and wealth distribution. We studied the evolution of market dynamics in different stages of historical development by analyzing commodity prices from two distinct periods : ancient Babylon, and medieval and early modern England. We find that the first-digit distributrions of both Babylon and England commodity prices follow Benford's Law, indicating that the data represent empirical observations typically arising from a free market. Further, we find that the normalized prices of both Babylon and England agricultural commodities are characterized by stretched exponential distributions, and exhibit persistent correlations of a power law type over long periods of up to several centuries, in contrast to contemporary markets. Our findings suggest that similar market interactions may underlie the dynamics of ancient agricultural commodity prices, and that these interactions may remain stable across centuries. To further investigate the dynamics of markets, we present the analogy between transfers of money between individuals and the transfer of energy through particle collisions by means of the kinetic theory of gases. We introduce a theoretical framework of how micro rules of trading lead to the emergence of income and wealth distribution. Particularly, we study the effects of different types of distribution of savings/investments among individuals in a society and different welfare/subsidies redistribution policies. Results show that while considering savings propensities, the models approach empirical distributions of wealth quite well. The effect of redistribution better captures specific features of the distributions which earlier models failed to do. Moreover, the models still preserve the exponential decay observed in empirical income distributions reported by tax data and surveys. / by Natalia E. Romero. / Vita. / Thesis (Ph.D.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.

The main objective of this work is to propose new procedures for the general dynamic factor analysis<p>introduced by Forni et al. (2000). First, we develop an identification method for determining the number of common shocks in the general dynamic factor model. Sufficient conditions for consistency of the criterion are provided for large n (number of series) and T (the series length). We believe that our procedure can shed<p>light on the ongoing debate on the number of factors driving the US or Eurozone economy. Second, we show how the dynamic factor analysis method proposed in Forni et al. (2000), combined with our identification method, allows for identifying and estimating joint and block-specific common factors. This leads to a more<p>sophisticated analysis of the structures of dynamic interrelations within and between the blocks in suchdatasets.<p>Besides the framework of the general dynamic factor model we also propose a consistent lag window spectral density estimator based on multivariate M-estimators by Maronna (1976) when the underlying data are coming from the alpha mixing stationary Gaussian process. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

The thesis consists of four chapters. The introductory chapter clarifies different notions of rationality used by economists and gives a summary of the remainder of the thesis. Chapter 2 proposes an explanation for the common empirical observation of the coexistence of infrequently-changing regular price ceilings and promotion-like price patterns. The results derive from enriching an otherwise standard, albeit stylized, general equilibrium model with two elements. First, the consumer-producer interaction is modeled in the spirit of the price dispersion literature, by introducing oligopolistic markets, consumer search costs and heterogeneity. Second, consumers are assumed to be boundedly-rational: In order to incorporate new information about the general price level, they have to incur a small cognitive cost. The decision whether to re-optimize or act according to the obsolete knowledge about prices is itself a result of optimization. It is shown that in this economy, individual retail prices are capped below the monopoly price, but are otherwise flexible. Moreover, they have the following three properties: 1) An individual price has a positive probability of being equal to the ceiling. 2) Prices have a tendency to fall below the ceiling and then be reset back to the cap value. 3) The ceiling remains constant for extended time intervals even when the mean rate of inflation is positive. Properties 1) and 2) can be associated with promotions and properties 1) and 3) imply the emergence of nominal price rigidity. The results do not rely on any type of direct costs of price adjustment. Instead, price stickiness derives from frictions on the consumers’ side of the market, in line with the results of several managerial surveys. It is shown that the developed theory, compared to the classic menu costs-based approach, does better in matching the stylized facts about the reaction of individual prices to inflation. In terms of quantitative assessment, the model, when calibrated to realistic parameter values, produces median price ceiling durations that match values reported in empirical studies.<p><p>The starting point of the essay in Chapter 3 is the observation that the baseline New-Keynesian model, which relies solely on the notion of infrequent price adjustment, cannot account for the observed degree of inflation sluggishness. Therefore, it is a common practice among macro- modelers to introduce an ad hoc additional source of persistence to their models, by assuming that price setters, when adjusting a price of their product, do not set it equal to its unobserved individual optimal level, but instead catch up with the optimal price only gradually. In the paper, a model of incomplete adjustment is built which allows for explicitly testing whether price-setters adjust to the shocks to the unobserved optimal price only gradually and, if so, measure the speed of the catching up process. According to the author, a similar test has not been performed before. It is found that new prices do not generally match their estimated optimal level. However, only in some sectors, e.g. for some industrial goods and services, prices adjust to this level gradually, which should add to the aggregate inflation sluggishness. In other sectors, particularly food, price-setters seem to overreact to shocks, with new prices overshooting the optimal level. These sectors are likely to contribute to decreasing the aggregate inflation sluggishness. Overall, these findings are consistent with the view that price-setters are boundedly-rational. However, they do not provide clear-cut support for the existence of an additional source of inflation persistence due to gradual individual price adjustment. Instead, they suggest that general equilibrium macroeconomic models may need to include at least two types of production sectors, characterized by a contrasting behavior of price-setters. An additional finding stemming from this work is that the idiosyncratic component of the optimal individual price is well approximated by a random walk. This is in line with the assumptions maintained in most of the theoretical literature. <p><p>Chapter 4 of the thesis has been co-authored by Julia Lendvai. In this paper a full-fledged production economy model with Kahneman and Tversky’s Prospect Theory features is constructed. The agents’ objective function is assumed to be a weighted sum of the usual utility over consumption and leisure and the utility over relative changes of agents’ wealth. It is also assumed that agents are loss-averse: They are more sensitive to wealth losses than to gains. Apart from the changes in the utility, the model is set-up in a standard Real Business Cycle framework. The authors study prices of stocks and risk-free bonds in this economy. Their work shows that under plausible parameterizations of the objective function, the model is able to explain a wide set of unconditional asset return moments, including the mean return on risk-free bonds, equity premium and the Sharpe Ratio. When the degree of loss aversion in the model is additionally assumed to be state-dependent, the model also produces countercyclical risk premia. This helps it match an array of conditional moments and in particular the predictability pattern of stock returns. / Doctorat en Sciences économiques et de gestion / info:eu-repo/semantics/nonPublished