Credit constraints and investment behavior in Mexico's rural economy

This paper uses two recently completed surveys of individual entrepreneurs (farmers and microentrepreneurs) and registered enterprises (agricultural and nonagricultural) operating in Mexico’s rural sector to provide new evidence about the factors influencing the incidence of credit constraints and investment behavior. To measure the incidence of credit constraints, the authors use self-reported information on whether economic agents have a demand for loans, separating formal and informal markets. They define credit constraints as a situation where rural agents report an unsatisfied demand for loans (formal or informal), which originates from rural agents having projects that are too risky or from impediments hindering the ability of rural agents and lenders to reduce information asymmetries. The authors find that the self-reported demand for loans is low. Nevertheless, the incidence of credit constraints is pervasive, especially among individual entrepreneurs. The low use of loans has consequences for the amount of investments that occur in the rural economy, posing a major obstacle to Mexico’s convergence towards its NAFTA partners. The empirical analysis, which includes proxies of business prospects and creditworthiness, shows that improving the availability of loans to credit constrained agents would increase the number of agents making investments and their investment to capital ratios.Access to Finance,,Debt Markets,Bankruptcy and Resolution of Financial Distress,Banks&Banking Reform

The expectations hypothesis of the term structure: some empirical evidence for Portugal

The purpose of this paper is to test the (rational) expectations hypothesis of the term structure of interest rates using Portuguese data for the interbank money market. The results obtained support only a very weak, long-run or "asymptotic" version of the hypothesis, and broadly agree with previous evidence for other countries. The empirical evidence supports the cointegration of Portuguese rates and the "puzzle" well known in the literature: although its forecasts of future short-term rates are in the correct direction, the spread between longer and shorter rates fails to forecast future longer rates. In the single equation framework, the implications of the hypothesis in terms of the predictive ability of the spread are also clearly rejected

Parameter estimation for macroscopic pedestrian dynamics models from microscopic data

In this paper we develop a framework for parameter estimation in macroscopic pedestrian models using individual trajectories -- microscopic data. We consider a unidirectional flow of pedestrians in a corridor and assume that the velocity decreases with the average density according to the fundamental diagram. Our model is formed from a coupling between a density dependent stochastic differential equation and a nonlinear partial differential equation for the density, and is hence of McKean--Vlasov type. We discuss identifiability of the parameters appearing in the fundamental diagram from trajectories of individuals, and we introduce optimization and Bayesian methods to perform the identification. We analyze the performance of the developed methodologies in various situations, such as for different in- and outflow conditions, for varying numbers of individual trajectories and for differing channel geometries

Transfer Pricing Rules, OECD Guidelines, and Market Distortions

We study the impact of transfer pricing rules on sales prices, firms’ organizational structure, and consumers’ utility within a two-country monopolistic competition model featuring source-based profit taxes that differ across countries. Firms can either become multinationals, i.e., they serve the foreign market through a fully controlled affiliate; or they can become exporters, i.e., they serve the foreign market by contracting with an independent distributor. Compared to the benchmark cases, where tax authorities are either unable to audit firms or where they are able to audit them perfectly, the use of the OECD’s Comparable Uncontrolled Price (CUP) or Cost-Plus (CP) rule distorts firms’ output and pricing decisions. The reason is that the comparable arm’s length transactions between exporters and distributors, which serve as benchmarks, are not efficient. We show that implementing the CUP or CP rules is detrimental to consumers in the low tax country, yet benefits consumers in the high tax country.Transfer pricing, OECD guidelines, multinationals and exporters, organizational choice, arm's length principle

Perfect (super) Edge-Magic Crowns

A graph G is called edge-magic if there is a bijective function f from the set of vertices and edges to the set {1,2,…,|V(G)|+|E(G)|} such that the sum f(x)+f(xy)+f(y) for any xy in E(G) is constant. Such a function is called an edge-magic labelling of G and the constant is called the valence. An edge-magic labelling with the extra property that f(V(G))={1,2,…,|V(G)|} is called super edge-magic. A graph is called perfect (super) edge-magic if all theoretical (super) edge-magic valences are possible. In this paper we continue the study of the valences for (super) edge-magic labelings of crowns Cm¿K¯¯¯¯¯n and we prove that the crowns are perfect (super) edge-magic when m=pq where p and q are different odd primes. We also provide a lower bound for the number of different valences of Cm¿K¯¯¯¯¯n, in terms of the prime factors of m.Postprint (updated version

Noise-enhanced classical and quantum capacities in communication networks

The unavoidable presence of noise is thought to be one of the major problems to solve in order to pave the way for implementing quantum information technologies in realistic physical platforms. However, here we show a clear example in which noise, in terms of dephasing, may enhance the capability of transmitting not only classical but also quantum information, encoded in quantum systems, through communication networks. In particular, we find analytically and numerically the quantum and classical capacities for a large family of quantum channels and show that these information transmission rates can be strongly enhanced by introducing dephasing noise in the complex network dynamics.Comment: 4 pages, 4 figures; See Video Abstract at http://www.quantiki.org/video_abstracts/1003587

The expectations hypothesis of the term structure: some empirical evidence for Portugal

The purpose of this paper is to test the (rational) expectations hypothesis of the term structure of interest rates using Portuguese data for the interbank money market. The results obtained support only a very weak, long-run or "asymptotic" version of the hypothesis, and broadly agree with previous evidence for other countries. The empirical evidence supports the cointegration of Portuguese rates and the "puzzle" well known in the literature: although its forecasts of future short-term rates are in the correct direction, the spread between longer and shorter rates fails to forecast future longer rates. In the single equation framework, the implications of the hypothesis in terms of the predictive ability of the spread are also clearly rejected.term structure of interest rates; expectations hypothesis; hypothesis testing; cointegration; Portugal

Fuzzy logic as a decision-making support system for the indication of bariatric surgery based on an index (MAFOI) generated by the association between body fat and body mass index.

Background: A fuzzy obesity index (MAFOI) for use as an alternative to bariatric surgery indication (BSI) is presented. The search for a more accurate method to evaluate obesity and to indicate a better treatment is important in the world health context. BMI (body mass index) is considered the main criteria for obesity treatment and BSI. Nevertheless, the fat excess related to the percentage of Body Fat (%BF) is actually the principal harmful factor in obesity disease that is usually neglected. This paper presents a new fuzzy mechanism for evaluating obesity by associating BMI with %BF that yields a fuzzy obesity index for obesity evaluation and treatment and allows building up a Fuzzy Decision Support System (FDSS) for BSI. Methods: Seventy-two patients were evaluated for both BMI and %BF. These data are modified and treated as fuzzy sets. Afterwards, the BMI and %BF classes are aggregated yielding a new index (MAFOI) for input linguistic variable are considered the BMI and %BF, and as output linguistic variable is employed the MAFOI, an obesity classification with entirely new classes of obesity in the fuzzy context as well as is used for BSI. Results: There is gradual, smooth obesity classification and BSI when using the proposed fuzzy obesity index when compared with other traditional methods for dealing with obesity.
Conclusion: The BMI is not adequate for surgical indication in all the conditions and fuzzy logic becomes an alternative for decision making in bariatric surgery indication based on the MAFOI