This article has considered the volume and direction of Iran’s trade using the gravity model. The major issue in this analysis is to explore why Iran over or under-traded with the 76 countries relative to the predicted trade flows of the model. The study attempts to explore the reasons from the respect of both the model itself and Iran’s trade structure. This is done by analysing the performanc...

OIC members have much potential in their economic development. Therefore, their economic integration leads to more increment for partners and deal with global system as a unique organization. Consequently, studying the convergence of OIC members and their encountered challenges has especial importance which can assist the policy makers to develop their commercial relationship and consequent...

A new gravity model with the function F (R) = (1/β) arctan (βR− βR) instead of the Ricci scalar in the Einstein–Hilbert action, describing inflation of the Universe, is suggested and analyzed. We obtain constant curvature solutions of the model in the Jordan frame. Performing the conformal transformation of the metric, the potential and the mass of a scalar degree of freedom in the Einstein fra...