Linking global economic dynamics to a South African-specific credit risk correlation model

In order to address practical questions in credit portfolio management it is necessary to link the cyclical or systematic components of firm credit risk with the firm's own idiosyncratic credit risk as well as the systematic credit risk component of every other exposure in the portfolio. This paper builds on the methodology proposed by Pesaran, Schuermann, and Weiner [Pesaran, M.H., Schuermann, T., and Weiner, S.M., (2004), Modeling regional interdependencies using a global error correcting macroeconometric model, Journal of Business and Economic Statistics, 22, 2, 129–169.] and supplemented by Pesaran, Schuermann, Treutler and Weiner [Pesaran, M.H., Schuermann, T., Treutler, B., and Weiner, S.M., (2006), Macroeconomic dynamics and credit risk: a global perspective, Journal of Money, Credit, and Banking, Volume 38, Number 5, August 2006, 1211–1261.] which has made a significant advance in credit risk modelling in that it avoids the use of proprietary balance sheet and distance-to-default data, focusing on credit ratings which are more freely available.In this paper a country-specific macroeconometric risk-driver engine which is compatible with and could feed into the GVAR model and framework of PSW (2004) is constructed, using vector error-correcting (VECM) techniques. This allows conditional loss estimation of a South African-specific credit portfolio but also opens the door for credit portfolio modelling on a global scale, as such a model can easily be linked to the GVAR model. The set of domestic factors is extended beyond those used in PSW (2004) in such a way that the risk-driver model is applicable for both retail and corporate credit risk. As such, the model can be applied to a total bank balance sheet, incorporating the correlation and diversification between both retail and corporate credit exposures.Assuming statistical over-identification restrictions, the results indicate that it is possible to construct a South African component for the GVAR model that can easily be integrated into the global component. From a practical application perspective the framework and model is particularly appealing since it can be used as a theoretically consistent correlation model within a South African-specific credit portfolio management tool.     

Characterizations of negative multinomial distributions based on conditional distributions

In this paper characterizations of negative multinomial distributions based on conditional distributions have been studied.     

Innovation, Imitation and Intellectual Property Rights: A Note on Helpman's Model

This note analyses the effect of the policy of tightening Intellectual Property Rights (IPR) on the rate of innovation in the North and on the welfare in both North and South in a model which is otherwise identical to Helpman (1993) except in the concept of knowledge capital. We assume that the South based imitated products do not contribute to the knowledge capital in the North. It is shown that the tightening of IPR raises the rate of innovation in the North and may improve the welfare of both North and South. These results are significantly different from those in Helpman (1993).     

Time-varying persistence in US inflation

The persistence property of inflation is an important issue not only for economists, but especially for central banks, given that the degree of inflation persistence determines the extent to which central banks can control inflation. Further, not only is it the level of inflation persistence that is important in economic analyses, but also the question of whether the persistence varies over time, for instance, across business cycle phases, is equally pertinent, since assuming constant persistence across states of the economy is sure to lead to misguided policy decisions. Against this backdrop, we extend the literature on long-memory models of inflation persistence for the US economy over the monthly period of 1920:1–2014:5, by developing an autoregressive fractionally integrated moving-average-generalized autoregressive conditional heteroskedastic model with a time-varying memory coefficient which varies across expansions and recessions. In sum, we find that inflation persistence does vary across recessions and expansions, with it being significantly higher in the former than in the latter. As an aside, we also show that persistence of inflation volatility is higher during expansions than in recessions. Understandably, our results have important policy implications.     

An empirical study of the dimensionality of organizational justice and its relationship with organizational citizenship behaviour in the Indian context

Cross-cultural research shows that while the concerns about organizational justice may be universal, operationalization of justice standards is highly particularistic (Greenberg 2001). The present study explores the dimensionality of organizational justice in the Indian context. Apart from procedural justice, interpersonal justice and informational justice, another justice dimension, labelled as empowerment justice, emerged during the study. Next, the study tests the relationships between justice dimensions and Organ's (1988) 5-factor conceptualization of organizational citizenship behaviour (OCB), namely helping, compliance, sportsmanship, courtesy and civic virtue behaviours. The perception of empowerment justice influences helping, compliance, sportsmanship, and civic virtue dimensions of OCB. Interpersonal justice significantly predicts courtesy behaviour. Implications for theory and practice are discussed.     

Rural-urban migration,informal sector and development policies: a theoretical analysis

"A theoretical model of rural-urban migration has been developed with special reference to the informal sector. The wage rate and employment in the informal sector are determined endogenously. The paper shows the simultaneous existence of open unemployment and informal sector in the urban area in migration equilibrium. The effects of alternative subsidy policies on unemployment and welfare of the workers are studied." The model is intended primarily for use in analyzing trends and policies in developing countries.     

The R&D-Marketing Interface in High-Technology Firms

It has become part of the traditional wisdom that good relationships between the R&D and marketing departments are essential for effective new product development. But in so many firms it still just doesn't happen. How come? In this article, three pragmatic researchers, Professors Gupta, Raj, and Wilemon, take another look at what causes the significant barriers that exist at the interface of two of the key product innovation functions. What they discover is disagreement between marketing and R&D people about what they should do together. They also find that R&D people are the more reluctant cooperators. They draw some interesting opinions from the parties as to why the barriers exist.     

Congruence between spokesperson and product type: A matchup hypothesis perspective

This study tested the matchup hypothesis regarding choice of celebrity spokesperson by examining the fit or congruence between image type and the product advertised from an Identification and Internalization viewpoint (Kelman, 1961). Spokesperson type (celebrity versus noncelebrity) was varied, aong with congruence between spokesperson image and product (higher versus lower congruence) in a 2x2 factorial design. Results showed that increased congruence for the spokesperson/product combination resulted in the perception of higher believability and attractiveness of the spokesperson and a more favorable product attitude. The implications of these and other findings for advertising and marketing strategy are discussed. © 1994 John Wiley & Sons, Inc.     

Do sunspot numbers cause global temperatures? Evidence from a frequency domain causality test

This article applies the causality test in the frequency domain, developed by Breitung and Candelon (2006), to analyse whether sunspot numbers (used as a partial approximation to solar irradiance) cause global temperatures, using monthly data covering the time period 1880:1–2013:9. While standard time domain Granger causality test fails to reject the null hypothesis that sunspot numbers do not cause global temperatures for both full and sub-samples (identified based on tests of structural breaks), the frequency domain causality test detects predictability for both the full-sample and the last sub-sample at short (2–2.6 months) and long (10.3 months and above) cycle lengths, respectively. Our results highlight the importance of analysing causality using the frequency domain test, which, unlike the time domain Granger causality test, allows us to decompose causality by different time horizons, and hence, could detect predictability at certain cycle lengths even when the time domain causality test might fail to pick up any causality. Further, given the widespread discussion in the literature, those results for the full-sample causality, irrespective of whether it is in time or frequency domains, cannot be relied upon when there are structural breaks present, and one needs to draw inference regarding causality from the sub-samples, we can conclude that there has been an emergence of causality running from sunspot numbers to global temperatures only recently at cycle length of 10.3 months and above.