Learning an Unknown Network State in Routing Games

We study learning dynamics induced by myopic travelers who repeatedly play a routing game on a transportation network with an unknown state. The state impacts cost functions of one or more edges of the network. In each stage, travelers choose their routes according to Wardrop equilibrium based on public belief of the state. This belief is broadcast by an information system that observes the edge loads and realized costs on the used edges, and performs a Bayesian update to the prior stage's belief. We show that the sequence of public beliefs and edge load vectors generated by the repeated play converge almost surely. In any rest point, travelers have no incentive to deviate from the chosen routes and accurately learn the true costs on the used edges. However, the costs on edges that are not used may not be accurately learned. Thus, learning can be incomplete in that the edge load vectors at rest point and complete information equilibrium can be different. We present some conditions for complete learning and illustrate situations when such an outcome is not guaranteed

A knowledge-based system design/information tool for aircraft flight control systems

Research aircraft have become increasingly dependent on advanced control systems to accomplish program goals. These aircraft are integrating multiple disciplines to improve performance and satisfy research objectives. This integration is being accomplished through electronic control systems. Because of the number of systems involved and the variety of engineering disciplines, systems design methods and information management have become essential to program success. The primary objective of the system design/information tool for aircraft flight control system is to help transfer flight control system design knowledge to the flight test community. By providing all of the design information and covering multiple disciplines in a structured, graphical manner, flight control systems can more easily be understood by the test engineers. This will provide the engineers with the information needed to thoroughly ground test the system and thereby reduce the likelihood of serious design errors surfacing in flight. The secondary objective is to apply structured design techniques to all of the design domains. By using the techniques in the top level system design down through the detailed hardware and software designs, it is hoped that fewer design anomalies will result. The flight test experiences of three highly complex, integrated aircraft programs are reviewed: the X-29 forward-swept wing, the advanced fighter technology integration (AFTI) F-16, and the highly maneuverable aircraft technology (HiMAT) program. Significant operating anomalies and the design errors which cause them, are examined to help identify what functions a system design/information tool should provide to assist designers in avoiding errors

Businessmen's Expectations Are Neither Rational nor Adaptive

A framework which allows for the joint testing of the adaptive and rational expectations hypotheses is presented. We assume joint normality of expectations, realizations and variables in the information set, allowing for parsimonious interpretation of the data; conditional first moments are linear in the conditioning variables, and we can easily recover regression coefficients from them and test simple hypotheses by imposing zero restrictions on these coefficients. The nature of the data, which are responses to business surveys and are all categorical, requires simulation techniques to obtain full information maximum likelihood estimates. We use a latent variable model which allows for the construction of a simple likelihood function. However, this likelihood contains multi-(four)dimensional integrals, requiring simulators to evaluate. Simulated maximum-likelihood estimation is carried out using the Geweke-Hajivassilou-Keane (GHK) method, which is consistent and has low variance. The latter is crucial when maximizing the log-likelihood directly. Identification of the parameters is achieved by placing restrictions on the response thresholds and/or the variances. We find that we can reject both hypotheses. --

Designing and implementing a tool to transform source code to UML diagrams

Currently, reverse engineering is considered as a significant process to extract the design information and abstractions of a system from the present software. The extracted source codes have been converted into a certain structure to be easily analyzed in the following procedure. For facilitating the software process development, it might be optimum to have tools beingcertain which generate automatically or help UML generating models from the codes as a source. The current study focuses on the reverse engineering process regarding the python and java source codes to the behavior diagrams: the use case and the activity diagrams which might be of high importance in the process of software maintenance. This approach is carried out in the current study in the application referred to as the RCUML tool with the use of the python language which helped in understanding python and java source codes in the software application, and enabling visualization regarding the software behavior

The school reentry decision on poor girls: structural estimation and policy analysis using PROGRESA database

In this paper I present a dynamic structural model of girls' schooling choices and estimate it using the Mexican PROGRESA database. This structural approach allows evaluating the efectiveness of several policies to increase school reentry rates for girls in low-income households. To increase school attendance among poor children in developing countries, policy makers have implemented conditional cash transfers programs. Although transfers have been successful in keeping girls at school, they do not increase school attendance among girls who have dropped out of school. Cash transfer programs may fail because most of these poor girls leave school to stay at home helping in housework, rather than working for a salary. Results suggest that effective policies to increase school reentry rates for poor girls are free access to community nurseries and kindergartens, and increasingg the availability of secondary schools.Policy evaluation, Dynamic discrete choice structural models, School choices for girls, School reentry, PROGRESA

How Pension Rules Affect Work and Contribution Patterns: A Behavioral Model of the Chilean Privatized Pension System

Chile has been at the forefront of pension reform, having switched in 1980 from a pay-as-you-go system to a fully funded privatized accounts system. The Chilean system served as a model for reform in many other Latin American countries and has also been considered by U.S. policy makers as a possible prototype for social security reform. Some of the criticisms of the Chilean system are low coverage rates and contributions rates among certain segments of the population. In 2006, the Chilean government proposed some reforms aimed at increasing coverage and contribution rates and expanding the safety net provided by the system to poor households. This study evaluates how changes in pension system rules affect working behavior and pension contribution patterns using data from a new Chilean household survey administered in 2002 and 2004 linked with administrative data from the pension regulatory agency. It develops and estimates a dynamic model of decision-making about working in the covered or uncovered sectors of the economy and studies implications for pension accumulations. The estimated model is used to simulate behavior under different pension system rules, such as a change in the number of years of contributions required for the minimum pension or a change in pension plan fees.

Strategic Interaction With Multiple Tools: A New Empirical Model

The Lanchester model of strategic interaction typically considers only two-firm rivalry and one strategic tool. This paper presents an alternative that considers rivalry among several firms using multiple tools. Marketing decisions are dynamically optimal and use equations of motion for market share that are consistent with optimal consumer choice. Using a single-market case study that consists of five years of monthly data on ready to eat cereal sales, advertising, product development investments and new product introductions, we test our model against a similar Lanchester specification. Non-nested specification tests fail to reject the proposed model, but reject the Lanchester alternative.advertising, brands, cereal, dynamic, Lanchester, oligopoly, strategic interaction., Marketing,

Academic Predictors and Characteristics of Self-Reported Juvenile Firesetting

The main purpose of this study was to address gaps in existing research by examining the relationship between academic performance and attention problems with juvenile firesetting. Two datasets from the Achenbach System for Empirically Based Assessment (ASEBA) were used. The Factor Analysis Dataset (N = 975) was utilized and results indicated that adolescents who report lower academic performance are more likely to set fires. Additionally, adolescents who report a poor attitude toward school are even more likely to set fires. Logistic regressions were run to determine if attention problems predicted firesetting and the findings indicated that attention problems are predictive of self-reported firesetting. The National Survey Dataset (N =1,158) was analyzed to determine the prevalence of firesetting in a normative sample and also examine whether these children reported higher levels of internalizing and externalizing behavior problems. It was found that 4.5% of adolescents in the generalized sample reported firesetting. The results of t-tests indicate that firesetters reported more internalizing, externalizing and total problems than their non-firesetting peers. In this normative sample, firesetters were found to have lower academic performance and more attention problems. Limitations include the low overall number of firesetters in each dataset (Factor Analysis n = 123 and National Survey n = 53) and the inclusion of children who had been referred for services in the Factor Analysis Dataset. Future research may include exploring other characteristics of firesetters from the data available and also utilizing this data to assist with intervention and assessment of firesetting behavior

Auxiliary-Path-Assisted Digital Linearization of Wideband Wireless Receivers

Wireless communication systems in recent years have aimed at increasing data rates by ensuring flexible and efficient use of the radio spectrum. The dernier cri in this field has been in the area of carrier aggregation and cognitive radio. Carrier aggregation is a major component of LTE-Advanced. With carrier aggregation, a number of separate LTE carriers can be combined, by mobile network operators, to increase peak data rates and overall network capacity. Cognitive radios, on the other hand, allow efficient spectrum usage by locating and using spatially vacant spectral bands. High monolithic integration in these application fields can be achieved by employing receiver architectures such as the wideband direct conversion receiver topology. This is advantageous from the view point of cost, power consumption and size. However, many challenges exist, of particular importance is nonlinear distortion arising from analog front-end components such as low noise amplifiers (LNA). Nonlinear distortions especially become severe when several signals of varying amplitudes are received simultaneously. In such cases, nonlinear distortions stemming from strong signals may deteriorate the reception of the weaker signals, and also impair the receiver’s spectrum sensing capabilities. Nonlinearity, usually a consequence of dynamic range limitation, degrades performance in wideband multi-operator communications systems, and it will have a notable role in future wireless communication system design. This thesis presents a digital domain linearization technique that employs a very nonlinear auxiliary receiver path for nonlinear distortion cancellation. The proposed linearization technique relies on one-time adaptively-determined linearization coefficients for cancelling nonlinear distortions. Specifically, we take a look at canceling the troublesome in-band third order intermodulation products using the proposed technique. The proposed technique can be extended to cancel out both even and higher order odd intermodulation products. Dynamic behavioral models are used to account for RF nonlinearities, including memory effects which cannot be ignored in the wideband scenario. Since the proposed linearization technique involves the use of two receiver paths, techniques for correcting phase delays between the two paths are also introduced. Simplicity is the hallmark of the proposed linearization technique. It can achieve up to +30 dBm in IIP3 performance with ADC resolution being a major performance bottleneck. It also shows strong tolerance to strong blocker nonlinearities