A MATHEMATICAL APPROACH TO HARROD'S OPEN ECONOMY DYNAMICS

This paper investigates an open economy dynamic model in the Harrod tradition. Its goal is to check if in accordance with Harrod's thought, opening to foreign trade is able to reduce the cyclical instability the economic system exhibits when it is closed to the international trade. We show that the system's dynamic behavior depends on changes in the saving rate, the competitiveness of home products in the foreign markets and the initial sign of the balance of trade. We demonstrate that stable cycles are possible only under particular conditions. Otherwise, the economy may experience chaotic motions in the long period.     

TRANSITIONS OUT OF UNEMPLOYMENT: THE ROLE OF SOCIAL NETWORKS' TOPOLOGY AND FIRMS' RECRUITMENT STRATEGIES

In this paper we study the effects of job contact networks on out‐of‐unemployment transitions. We find that social connections produce sizable increases in upward mobility from unemployment and, caeteris paribus, symmetric network topologies perform better than asymmetric ones. Furthermore, in scale‐free networks the probability of transitions out of unemployment increases in the exponent of the power‐law degree distribution, but its value is much lower than the one attainable in Poisson random networks. In addition, and most interestingly, these results strongly depends on the different hypotheses on the firms' recruitment strategy.     

The Relationship Between Spiritual Well-Being and Ethical Orientations in Decision Making: An Empirical Study with Business Executives in Australia

The purpose of this study was to determine the applicability of Buddhist practices in today’s workplaces. The findings were supported by interviews with Buddhist masters and Buddhist business practitioners, as well as literature review, through phenomenological analysis. As a means of presenting the main reasons why Buddhist practices should be considered in contemporary workplaces, a SWOT analysis is presented. In this analysis, a number of strengths for using Buddhist practices in workplaces are listed such as pro-scientific, greater personal responsibility, and healthy detachment, while potential weaknesses such as non-harming, equanimity, and no competition are also reviewed. Both the strengths and the weaknesses could be listed in reverse if applied to a different extent. Among the opportunities were issues such as re-educating the world of business, enhancing personal ownership and a healthier society, while the threats comprised issues such as creating different imbalances, disinterest, and stationary development.     

Do unemployment benefits promote or hinder job reallocation?

According to recent and largely untested theories, unemployment benefits (UBs) could improve the extent and quality of job reallocation even at the cost of increasing unemployment. In this paper, we use a new set of yearly panel data from a large number of countries to evaluate empirically the relationship between unemployment benefits and job reallocation. Unlike previous work assessing the effects of UBs on labor market stocks, we focus on flows and rely on policy “experiments,” notably the introduction from scratch of unemployment benefits in many countries. We exploit the longitudinal nature of our data to lessen the potentially important selection, endogeneity, and omitted variable problems. We find a positive, sizable, and significant effect of the introduction of UBs on job reallocation, arising mainly from the job destruction margin although this effect fades away over time. These findings appear to be robust to changes in the countries in the sample, control variables or estimation methods. We discuss to what extent our results are consistent with equilibrium matching models with or without endogenous sorting of workers into jobs providing entitlement to UBs and stochastic job matching.     

The contribution of trout fly fishing to the economy of Rhodes,North Eastern Cape,South Africa

Recent government legislation, which calls for the eradication of trout from ecosystems where they may cause harm, could damage the tourism appeal of many South African catchments. However, no South African studies have tried to quantify the economic impact of removing trout from rivers and streams. This study aimed first to value the Rhodes trout fishery, North Eastern Cape, South Africa, and second to assess whether the trout fly fishing industry in Rhodes could form the foundation for the implementation of a local economic development initiative. Overall, the study found that the trout fishing industry directly generates approximately R5 658 240 per annum, and sustains a minimum of 39 direct job opportunities for the community of Rhodes, and can therefore provide the impetus for the creation of a tourism-based local economic development programme.     

Markov decision processes under model uncertainty

We introduce a general framework for Markov decision problems under model uncertainty in a discrete-time infinite horizon setting. By providing a dynamic programming principle, we obtain a local-to-global paradigm, namely solving a local, that is, a one time-step robust optimization problem leads to an optimizer of the global (i.e., infinite time-steps) robust stochastic optimal control problem, as well as to a corresponding worst-case measure. Moreover, we apply this framework to portfolio optimization involving data of the . We present two different types of ambiguity sets; one is fully data-driven given by a Wasserstein-ball around the empirical measure, the second one is described by a parametric set of multivariate normal distributions, where the corresponding uncertainty sets of the parameters are estimated from the data. It turns out that in scenarios where the market is volatile or bearish, the optimal portfolio strategies from the corresponding robust optimization problem outperforms the ones without model uncertainty, showcasing the importance of taking model uncertainty into account.     

Optimal insurance under maxmin expected utility

We examine a problem of demand for insurance indemnification, when the insured is sensitive to ambiguity and behaves according to the maxmin expected utility model of Gilboa and Schmeidler (J. Math. Econ. 18:141–153, 1989), whereas the insurer is a (risk-averse or risk-neutral) expected-utility maximiser. We characterise optimal indemnity functions both with and without the customary ex ante no-sabotage requirement on feasible indemnities, and for both concave and linear utility functions for the two agents. This allows us to provide a unifying framework in which we examine the effects of the no-sabotage condition, of marginal utility of wealth, of belief heterogeneity, as well as of ambiguity (multiplicity of priors) on the structure of optimal indemnity functions. In particular, we show how a singularity in beliefs leads to an optimal indemnity function that involves full insurance on an event to which the insurer assigns zero probability, while the decision maker assigns a positive probability. We examine several illustrative examples, and we provide numerical studies for the case of a Wasserstein and a Rényi ambiguity set.