Default estimation,correlated defaults,and expert information

Capital allocation decisions are made on the basis of an assessment of creditworthiness. Default is a rare event for most segments of a bank's portfolio and data information can be minimal. Inference about default rates is essential for efficient capital allocation, for risk management and for compliance with the requirements of the Basel II rules on capital standards for banks. Expert information is crucial in inference about defaults. A Bayesian approach is proposed and illustrated using prior distributions assessed from industry experts. A maximum entropy approach is used to represent expert information. The binomial model, most common in applications, is extended to allow correlated defaults yet remain consistent with Basel II. The application shows that probabilistic information can be elicited from experts and econometric methods can be useful even when data information is sparse. Copyright © 2009 John Wiley & Sons, Ltd.     

The house price determination process: Rational expectations with a spatial context

Applying the rational expectations hypothesis, this essay models the current value of a house as the conditional expectation of the discounted stream of housing services accruing to the owner of the house. The value of housing services is determined by neighborhood effects as well as the physical attributes of the property itself. In the existing hedonic literature, future transactions have not been utilized to describe neighborhood effects. The rational expectations asset pricing model in this study accounts for expected future neighborhood effects as well as observed current neighborhood effects. The reduced form of the rational expectations model is a spatial autoregressive (SAR) model with two spatial lags. After employing the generalized method of moments (GMM) in estimating the spatial asset pricing model, I find that both expected future transactions and prior transactions in the neighborhood are significant. The inclusion of expected future transaction prices in the neighborhood takes into account the influence of expected changes in the community and factors these potential changes into the current house price. This is consistent with forward-looking households. The forward-looking model generates superior out-of-sample prediction performance relative to both the conventional hedonic model without considering neighborhood effects or the standard spatial hedonic model including only past transactions.     

SEARCHING FOR ENDOGENOUS BUSINESS CYCLES IN THE U.S. POSTWAR ECONOMY

This paper explores the possibility that booms and busts are endogenous with an econometric examination of the U.S. economy. Although existing empirical results suggest the contrary, a theoretical literature discounts the stability verdict on the grounds that it is based on linear econometric evidence which is unreliable when the underlying phenomenon is non-linear. We study a simple Keynesian cycle model which is theoretically general enough to include convergence to equilibrium or endogenous cycles as special cases. We find one particular nonlinear econometric specification which exhibits a limit cycle when estimated on postwar data, while the estimate of its global linear approximation converges to a fixed equilibrium. Our results are an empirical investigation of the boundary between stability and instability.     

Doubts Regarding the Human Capital Theory of Racial Inequality

Using wage data developed by Smith (1984), this paper compares human capital and institutional explanations of trends in the racial wage gap since 1890. While a regression including daily schooling variables is consistent with the human capital theory, so is an institutional model which omits schooling variables but adds the influences of isolation in the rural South, discriminatory hiring and promotion practices, unemployment, and government policy. Including schooling and institutional variables together casts doubt on the relative importance of schooling compared to labor market demands and political variables.     

Specification diagnostics based on Laguerre alternatives for econometric models of duration

Score tests of the null hypothesis of exponentially distributed durations (conditional on regressors) against alternatives in a family of approximations to arbitrary distributions for non-negative random variables are developed. The test statistics take a simple, easily calculated and interpreted form. The alternatives considered are expansions of various orders in Laguerre polynomials. An economic model generating exponential unemployment duration is presented. The statistics are applied in a look at unemployment durations in the Denver Income Maintenance Experiment data.     

On the contribution of eco-innovation features to a circular economy: A microlevel quantitative approach

The circular economy (CE) and eco-innovation (EI) are two concepts deemed instrumental in achieving a sustainable transition. They have been proposed in the academic literature and by practitioners and have acquired very high public policy relevance, being endorsed by policymakers and ultimately leading to regulations supporting them. It has been argued that both concepts are compatible and interrelated and that EI is instrumental in achieving the CE. However, little is known about how different EI features contribute to the CE at the microlevel. This article tries to cover this gap. Its aim is to assess and quantify the causal relationship between different EI features and the CE with the help of a unique dataset of small- and medium-sized firms in Spain and an econometric analysis. Our results show that only systemic EIs contribute to a global CE, whereas other EI types such as component additions or small changes in existing production processes could even be barriers to high levels of circularity. It is found out that technological novelty is not relevant for reaching the CE. The results support the understanding of how EIs enable a transition to the CE. Care should be taken not to promote incremental EIs that do not only achieve low (or no) circularity but that effectively lock-in the economic system in solutions that entail a barrier to the achievement of high-level circularity.     

The Entrepreneurship Industry: Influences of the Goods and Services Marketed to Entrepreneurs

This paper constitutes the first comprehensive attempt to define and assess entrepreneurship as an industry, and it is the only study to date to empirically evaluate the extent to which the entrepreneurship industry (EI) is associated with entrepreneurial actions and outcomes. EI is defined as the goods and services explicitly intended for opportunity discovery and development by current and prospective entrepreneurs, an industry with $13 billion in annual revenue. In order to assess EI's influence, we employ a matched set comparison of EI consumers and nonconsumers, which reveals that high levels of EI consumption are associated with an increase in entrepreneurial activity but a decrease in performance and survival prospects. The findings address material gaps in existing frameworks by adding EI to the entrepreneurial contexts that exert a potent influence on the identification, development, and exploitation of opportunities.     

A simulation estimator for testing the time homogeneity of credit rating transitions

The measurement of credit quality is at the heart of the models designed to assess the reserves and capital needed to support the risks of both individual credits and portfolios of credit instruments. A popular specification for credit-rating transitions is the simple, time-homogeneous Markov model. While the Markov specification cannot really describe processes in the long run, it may be useful for adequately describing short-run changes in portfolio risk. In this specification, the entire stochastic process can be characterized in terms of estimated transition probabilities. However, the simple homogeneous Markovian transition framework is restrictive. We propose a test of the null hypotheses of time-homogeneity that can be performed on the sorts of data often reported. We apply the tests to 4 data sets, on commercial paper, sovereign debt, municipal bonds and S&P-rated Corporates. The results indicate that commercial paper looks Markovian on a 30-day time scale for up to 6 months; sovereign debt also looks Markovian (perhaps due to a small sample size); municipals are well-modeled by the Markov specification for up to 5 years, but could probably benefit from frequent updating of the estimated transition matrix or from more sophisticated modeling, and S&P Corporate ratings are approximately Markov over 3 transitions but not 4.