Issue 48th of the academic journal Semestre Económico is composed of seven articles that deal with labor economics issues such as wage discrimination by gender, female labor market and informal economy. It also includes texts on environmental economics and the public sector, such as mining conflicts, mining fiscal policy, extractivism and natural resources. Likewise, about business economy and regional development, such as agglomeration economies, the micro-enterprises competitive behavior and business classification; additionally, about economic development issues and commercial policy, such as industrial promotion, economic planning, technical contraband or smuggling and tariff policy. Five of the seven papers presented in this issue are research papers, one is a review article and the other is a reflection article. Five of these were carried out by Colombian academics and two by foreign researchers. Of the thirteen authors, five are foreigners.

In the first paper, Camilo Fabiam Gómez Segura and Óscar Hernán Cerquera Losada, from the Universidad Surcolombiana (Huila, Colombia), and Cristian Felipe Orjuela Yacue, from the Universidad Uniminuto (Huila, Colombia), analyze the determinants of the gender wage gap in Colombia during 2004-2012 using the MesepDANE surveys of 2004. Results show that the characteristic effect explains the gross gap and its progress in salary distribution, which evidences the existence of a glass ceiling for women; although they have sufficient human capital to obtain jobs with better income, the glass ceiling prevents them from getting jobs that position them in the middle of wage distribution.

The second paper, written by Mayda Alejandra Calderón Díaz, Economics PhD, candidate at the Universidad Nacional de Colombia, internal researcher and academic visitor of Middlesex University (London, United Kingdom), presents a literature review on informal economy and women’s work. She undergoes a bibliographic review of the most cited contributions in specialized journals and books that are current references for the concepts of women’s work, informal economy, women’s informal work, as well as criticisms to the concept of informality. The result of the review shows the existence of two positions: in the first of them, the phenomenon of informality is understood as an involuntary refuge, while the second one -to which the author in reference ascribes- represents the legalistic position of informality, which views it as an option to evade taxes.

In the third article, Víctor Torres Cuzcano, from the Universidad Nacional Mayor de San Marcos (Lima, Peru), analyzes the mining fiscal policy of Peruvian governments during the mining bonanza period between 2003 and 2012. To do this, the paper evaluates the accuracy of fiscal instruments implemented during the increase in price of metals that took place in this period. The results show that the applied instruments lacked efficiency to assure an optimal State appropriation of the mineral rents. Due to this, two alternative instruments are proposed: the ad valorem royalties and the tax on income of natural resources.

In the fourth paper, Mario Alberto Gaviria Ríos from the Universidad Católica de Pereira (Pereira, Colombia), makes a spatial analysis (applying a fixed-effects panel) of the city system of the Eje Cafetero in Colombia (Colombian coffee growing axis). This work evidences that there are external network economies in the studied urban scale. Due to this, it is necessary that intermediate cities associate to neighboring urban centers and develop economic, social and political synergies that will allow them to enjoy the advantages of agglomeration at a regional scale, without having to assume the costs of economic activity concentration and population.

In the fifth article, researchers from the Universidad Autónoma de Baja California (Mexico) Germán Osorio Novela, Alejandro Mungaray Lagarda, José G. Aguilar Barceló and Natanael Ramírez Angulo, apply a mixed methodology that implies contrasting empirical evidences and essential assumptions made by the industrial organization theory; as well as applying measurement instruments for strategic competence degree and microenterprise classification. The purpose is to rethink the theoretical reference framework for the analysis of the microenterprise sector and its competitive behavior. The results suggest that it is possible to associate the competitive performance of an important subsector of microenterprises with imperfect competition models.

In the sixth paper, Carolina Vélez Ospina, economics student at the Universidad de Antioquia (Medellín, Colombia), and Edwin Esteban Torres Gómez, professor and researcher at the Universidad de Antioquia (Medellín, Colombia), evaluate the effect of tariff policy on contraband and the labor market’s situation from 1990 to the second decade of 2000, making use of econometric modeling for panel data. They conclude that the implemented policies did not meet their objective, there was an increase in illegal imports due to under-invoicing importations, as well as a depreciation in employees working conditions. This can be seen in a descent in work hours and represents a shift from formal to informal work. The results suggest that the policies had adverse effects on under-invoicing and on the hours worked by employees, mostly affecting informal employment.

The journal ends with a paper written by Medardo Alfonso Palomino Arias, who has taught in universities such as the Fundación Universitaria Lumen Gentium, Universidad Antonio Nariño and Corporación Universitaria Centro Superior, in Cali (Colombia). Palomino exposes an economic historiography synthesis of the greatest product growth period presented by the Union of Soviet Socialist Republics (USSR); it includes the industrialization phase between 1917 and 1960. The result refutes the idea that the country’s economic power derived from its large size and enormous endowment of natural resources. Instead, Palomino concludes that Soviet economic development and its accelerated material growth were due to political changes and economic policy decisions.