The purpose of this paper is to revisit the Granger causal relationship between banking sector development and economic growth for forty developing countries in the period 1970-2012. In order to capture the different aspects of banking sector development, we develop two banking sector development indices and apply the panel bootstrapped approach to Granger causality testing approach properly taking into account cross-sectional dependence and heterogeneity issues. The empirical results show limited support for the supply-leading, demand-following and complementarity hypotheses. Our results also provide evidence as the causal relationship between banking sector development and economic growth exists in twenty five countries.

Tax policy is among the most common and relevant instruments in the toolkit of policy-makers when thinking about promoting growth, yet there is not compelling evidence regarding its effect in Tunisia. Using a variety of approaches, we measure firstly the optimal tax burden rate using Scully's static model and the quadratic model. For Scully's static model, gross domestic product is the dependent variable. For the quadratic model, growth rate is a dependent variable explained by tax rate in level and in square. Secondly and according to stationary and cointegration test results, we focus on the long-term effects on gross domestic product of the important taxes, namely tax revenue and private receipts. In this second study, we use a basic Scully model and we develop a vector error correction model technique. Our results show that optimal tax burden rate has to be situated between 12.8% and 19.6% of gross domestic product which is widely lower than the current rates. The long-term analysis estimates an optimal rate of 14% of gross domestic product which can participate to increase economic growth, to stabilize the tax evasion and to encourage investment especially after the Tunisian revolution.

The article is an extension to the pricing models proposed by Jean Tirol that model the consumption of an environmental good. However, the different consumption patterns of this good, which is characterized by a taste parameter (two tastes or a continuum of taste); always verifying an imbalance between the profit of the monopoly (mainly natural); and the utility function of the consumer agent. Taxation on the price, in relation to consumer preferences, can ensure the objectives of an efficient management of a good which has variations in its physical nature. Moreover, a coefficient of variation in its nature, based on a scale of measurement, can achieve the convergence between economic and social objectives. The underlying results show that the consumer surplus is proportional to the variation between the average and marginal utility. In addition, maximizing monopoly profit provides a reasonable price that ensures social equity measures between the different users.

The present article aims to evaluate the actual water policy management and to see if it's efficient either in macroeconomic level or in the regional one. Thus, the authors have recoursed, to a new set of explanatory variables to estimate an extended demand function in the short and long-run. Indeed, they have assumed that distributed volume of water is determined by the number of connections to Water supply network, the distribution performance, the linear loss index recorded in the distribution system, the evolution of the length of the water network and the water tariffs. The main results of this study are that, at the macroeconomic level, the price of water seems to be an efficient tool to waste reduction only in the long run. Consequently, the efficiency can be established only in the long-run. Indeed, the Tunisian consumer needs more of time to adjust its behavior to avoid all possible water waste. Nevertheless, the estimation of the said relation by region has shown that it exists, a large disparity and inequity between them.

This article analyses the current situation of water management in Tunisia focusing on constraints to which this management is subject. The empirical results show the absence of a long-term equilibrium between production capacity and consumption patterns. This imbalance is characterized by a deficiency in the quantity of water produced, that is to say that the quantities applied for exceed those produced for future projection. Currently, as the closer one gets to a full phenomenon which is the use of available resources, a trend towards unconventional resources such as treated wastewater (TW) may solve the problem although partially.