**1. Foreword**

This article is written specially for the issue of Entropy, to commemorate 30 years of Econophysics, the discipline which appeared at the beginning of the 1990s at the cross-roads of economics, mainly finance, and theoretical physics, in particular many-body systems, thermodynamics, and phase transitions. It was driven primarily by physicists who, being generally curious about nature but not particularly educated about the specific field at the time, did not see any barriers to tackle almost any problem in finance they could think of. These would be, for example, the non-liner modeling of market prices, derivatives pricing, and non-equilibrium market dynamics, to name a few. This intellectual effort, coupled with a cheeky belief in technical superiority and nearly barbaric economic ignorance led to the situation when, in a relatively short period of time, truly cross-disciplinary problems, previously overlooked or simply perceived, hopelessly too complex, were posed and tackled.

To keep up with the tradition and in the general spirit of things, we do not want to present here just another paper on portfolio theory, generalized Sharpe ratios, or a new market forecasting technique—all the boringly routine daily subjects for finance professionals, the things the author actually thinks he now knows about. Instead, we aim to sketch here a new quantitative solution to an old problem in a field that is relatively new to the author. We consider the problem of transition to internationalization through export, export readiness, and forecasting of export success–the questions lying in the overlap of several economic fields, namely Theory of the Firm, International Trade and Finance, and Economics of Government Intervention. The proposed model utilizes objects and methods familiar to us from the field of quantitative finance, in particular capital structure modeling and derivatives pricing, which to our knowledge have not been used in this context before. In this way, we try to keep up with the original Econophysics tradition of solving problems we knew very little about until recently, using methods that earn us our daily keep.

**Citation:** Ilinski, K. Learning Your Options: Option-Based Model of Export Readiness and Optimal Export. *Entropy* **2022**, *24*, 173. https://doi.org/10.3390/e24020173

Academic Editors: Ryszard Kutner, Christophe Schinckus and H. Eugene Stanley

Received: 23 December 2021 Accepted: 20 January 2022 Published: 24 January 2022

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**Copyright:** © 2022 by the author. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

#### **2. Long Introduction—Setting Up the Context**
