Credit rating dynamics and Markov mixture models

Despite mounting evidence to the contrary, credit migration matrices, used in many credit risk and pricing applications, are typically assumed to be generated by a simple Markov process. Based on empirical evidence, we propose a parsimonious model that is a mixture of (two) Markov chains, where the mixing is on the speed of movement among credit ratings. We estimate this model using credit rating histories and show that the mixture model statistically dominates the simple Markov model and that the differences between two models can be economically meaningful. The non-Markov property of our model implies that the future distribution of a firm’s ratings depends not only on its current rating but also on its past rating history. Indeed we find that two firms with identical current credit ratings can have substantially different transition probability vectors. We also find that conditioning on the state of the business cycle or industry group does not remove the heterogeneity with respect to the rate of movement. We go on to compare the performance of mixture and Markov chain using out-of-sample predictions.     

Cost Inefficiency,Size of Firms and Takeovers

This study, using the Cox proportional hazards model, finds that the risk of takeover rises with cost inefficiency. It also finds that a firm faces a significantly higher risk of takeover if its cost performance lags behind its industry benchmark. Moreover, these findings appear to be remarkably stable over the nearly two decades spanned by the sample. The effect of the variables used to measure the risk-size relationship, however, indicates temporal changes. Lastly, the study presents evidence from fixed-effects models of ex post cost efficiency improvements that support the hypothesis that takeover targets are selected based on the potential for improvement.     

The Limits of Discipline: Ownership and Hard Budget Constraints in the Transition Economies

The existing literature on soft budget constraints suggests that firms may be subsidized for political reasons or because of the creditors' desire to recover a part of the sunk cost invested in an earlier period. In all these models hard budget constraints are viewed as being, in principle, capable of inducing the necessary restructuring behaviour on the level of the firm. This paper argues that the imposition of financial discipline is not sufficient to remedy ownership and governance-related deficiencies of corporate performance. Using evidence from the post-communist transition economies, the paper shows that a policy of hard budget constraints cannot induce successful revenue restructuring, which requires entrepreneurial incentives inherent in certain ownership types (most notably, outside investors). The paper also shows that the policy of hard budget constraints falters when state firms, because of inferior revenue performance and less willingness to meet payment obligations, continue to pose a higher credit risk than privatized firms. The brunt of state firms' lower creditworthiness falls on state creditors. But the 'softness' of these creditors, while harmful in many ways, is not necessarily irrational, if it prevents the demise of firms that are in principle capable of successful restructuring through ownership changes.     

ASYMPTOTIC INFERENCE FOR THE PARAMETERS OF A DISCRETE-TIME SQUARE-ROOT PROCESS

This paper is concerned with asymptotic properties of the maximum likelihood estimators for the discrete-time square-root process. This process and its generalizations are employed in financial literature as models for movements of asset prices. the considered process is nonergodic and therefore standard maximum likelihood theory does not apply. the nonstandard asymptotic theory is developed. Strong consistency of the estimators is established, joint asymptotic distribution of the properly normalized estimators is obtained and confidence intervals for the parameters are constructed. the results of the small simulation study are reported.     

Attachment styles and customers' long-term relationships in a service context

The main objective of this study is to use attachment styles theory to explore long-term relationships in a service context using the mobile market as a case study. Attachment theory focuses on the primary link between maternal loss or deprivation and later personality development. This theory was extended to adult life and commercial contexts. Three attachment styles (secure, avoidant, and anxious) were used as the independent variables. Commitment and trust, as constructs of any relationship, were employed as the mediating variables, while intention to stay and cooperation were adopted as the dependent variables, as indicators of long-term commercial relationships. A random sample of 1024 members of an online panel participated in the online survey. Structural equation modelling was performed to measure the validity of the constructs through confirmatory factor analysis, and to assess the hypothesized model as a single theoretical structure using path analysis. Associations were found between most of the study variables. Significant mediation effects were found between attachment styles and long-term relationship indicators, intention to stay, and cooperation, with trust and commitment as the mediators. This study employs a unique theoretical model that has not been previously tested. The model and findings demonstrate that primary psychological structures play a role in creating and maintaining long-term relationships.