International Journal of

Abstract:
The tax capacity is one of the main concepts in public finance and
provides the required information on state economic power in
mobilizing the tax resources for responding the financial problems
and execution of economic policies. For this purpose, the main
objective of this paper is to estimate the tax capacity for oil
exporting countries over the period of 1995-2008 by applying panel
data approach. The summary of results indicates that the GDP per
capita and trade openness are the main factors affecting the ratio of
tax revenue to GDP. Also, the empirical findings of this study
reveal that countries with a low share of oil exports have more
Potential tax capacities. Moreover, the potential tax capacity of Iran
is the same as its actual tax during the period of study.

Abstract
The main objective of this study was to examine the relationship between Value at Risk (VaR) and expected returns from 2002 to 2013 in Tehran’s Stock Exchange. In this study parametric value at risk, which considers the distribution of returns as normal and the historical value at risk as abnormal, was used to test the presence of the volatility anomaly in the companies listed in Tehran’s Stock Exchange. Also, this study controlled the impact of the variables (Firm size, Book value to Market value) and the relationship between Value at Risk and expected return.
The results of the analysis of the panel data showed a significant positive relationship between the parametric VaR , historical VaR and expected returns during the period under review .The results showed that the control variables didn’t have an effect on the relationship between Value at Risk and expected returns.