Application of Neural Networks to Short Time Series Composite Indexes: Evidence from the Nonlinear Autoregressive with Exogenous Inputs (NARX) Model

The aim of this paper is to extend the index of financial safety (IFS) approach with improving its predictive performance and to show the applicability of artificial neural networks to economic and financial short time series. To this end, prediction is performed by means of the nonlinear autoregressive with exogenous inputs (NARX) model that represents the neural networks and can emulate any nonlinear dynamic state space model. Thus, a NARX model, trained by means of Levenberg–Marquardt algorithm, was chosen since it gave the best performance. Results reveal that the NARX models are suitable for performing short time series composite indexes prediction.

     

Does political instability affect exchange rates in Arab Spring countries?

This article investigates the dynamic relationship between political instability and exchange rates in five Arab Spring countries over the period 1992Q1–2016Q4. We include macroeconomic fundamentals to identify the transmission channels through which political instability may affect exchange rates. Based on VAR and ARDL models, our results report that political instability is associated with a significant drop in the value of domestic currencies of these countries. Economic growth is found to be the key mechanism channel. We find also that the dependence between variables is more emphasized in the short run than in the long run.     

Banking, contract enforcement and economic growth

We develop a new model that links credit contracts enforcement to banking emergence and economic growth. It is shown that the development process is composed of three stages. In the first stage, the economy develops slowly due to a primitive technology of capital accumulation. The second stage marks the emergence of banking and the substitution of the primitive technology by a more productive modern technology that enhances growth. Finally in the third stage, our model enables the realization of a dynamic capital accumulation scenario without credit rationing. Another finding is that a reduction in the enforcement cost accelerates the emergence of the banking system.     

The performance effects of major workforce reductions: longitudinal evidence from North America

This paper investigates the performance effects of major job cuts.1 1 Like Wayhan and Werner (2000 Wayhan, V. and Werner, S. 2000. The Impact of Workforce Reductions on Financial Performance: A Longitudinal Perspective. Journal of Management, 26: 341–63. [Crossref] , [Google Scholar]), we interchangeably use the expressions ‘workforce reduction’ and ‘job cuts’ instead of the broad concept of ‘downsizing’ which is subject to multiple confusing definitions (DeWitt, 1998 DeWitt, R.L. 1998. Firm Industry and Strategy Influences on Choice of Downsizing Approach. Strategic Management Journal, 19: 59–79.  [Google Scholar]). Using data from Compustat S&P database, we examined the longitudinal impact of workforce reductions on labour productivity and operational indebtedness of 239 US and Canadian companies. Repeated measures analysis showed that firms that substantially cut jobs failed to improve their labour productivity and their operational indebtedness. Then, taken a step further, statistical analysis surprisingly revealed that firms that cut the highest proportions of their workforce had a significant deterioration of their operational indebtedness and a non-significant change of their labour productivity. These results call into question the economic legitimacy of major workforce reductions increasingly institutionalized to the detriment of the strategic approach of HRM.     

The effect of reducing quantitative easing on emerging markets

On 22 May and 19 June 2013, the US Federal Reserve (Fed) announced a reduction in the asset purchase programme of its quantitative easing policy. This article investigates the impact of this news on the currencies of emerging markets. Using event study methodology, our results report a global significant depreciation in the currencies of all emerging markets in our sample, but with different depreciation sizes from one market to another. To test whether the depreciation in currencies is driven by capital flow components, a regression analysis is performed. Inward FDI as well as outward FDI appear to have more explanatory power than inward and outward portfolio investment in explaining the impact. With the slowdown in asset purchases by the Fed, emerging countries have incurred large capital outflows from their markets to the US market, resulting in a drop in their currencies.