This section is organized around three issues: the scientific work and its academic impact, the socioeconomic impact and the impact on the management of scientific resources. My scientific work and its impact could be summarized in several indicators. as of March of 2018, I have published 139 articles and 17 books and monographs. I have been involved in 23 competitive research projects (13 as principal investigator or coordinator). Google Scholar counts 7,880 citations of my works with an index-h of 39. I was the first ranked economist working on applied economics, in terms of scientific impact (h-index), according to the latest ranking of economists working in Spain.

My first two papers were related to technical issues: an estimator of the generalized method of moments for panel data when the conditional expectation is not linear and there are predetermined variables (my estimator is used for example in papers of medical journals to estimate days of hospitalization), and the properties in small samples of cointegration estimators. From here my research moved towards the use of massive data. In the mid 90’s the “big data” was generated by the financial markets. I started by analyzing the risk premiums of the sovereign bonds of the countries of the European Monetary System. Using daily data, I constructed Markov models to predict the probability of exit from the SME mechanism. The following work used even more accurate and higher frequency data: the futures market on sovereign bonds. The information contained millions of observations with all transactions, “bids” and “asks” that occurred every second. This work showed that the introduction of new market makers effectively increased liquidity in financial markets.

My research in the late 1990s turned to issues relevant to economic policy, without neglecting the work with large databases. From the Spanish perspective, I was concerned about two issues: the high unemployment rate of young people (in 1996 it exceeded 50%) and the mismatch between education and employment. In this field I have written several books and many articles. The second research topic related to the Spanish issues was the accelerated credit and real estate expansion of the 2000s. Since 2003, I wrote many papers that showed, with scientific arguments, the building of a large real estate bubble in Spain. My research did not get much recognition among the policy makers until the financial crisis of 2007-08. The last work I have written, in collaboration with several coauthors, in this line, “The real state and the credit bubble: evidence from Spain”, won the award for the best article published by the Journal of the Spanish Economic Association, in the years 2014 and 2015.

At the level of international issues, my research has been very influenced by my work in the World Bank, and the coincidence of my arrival with the attacks of September 11, 2001. From that moment I center my work on relevant issues related to ethnic and religious diversity and its impact on economic development and conflicts; the evaluation of the effectiveness of development aid to alleviate poverty; and the causes and effects of terrorism. The result of the first line of research, joint with Marta Reynal-Querol, was the formalization of a discrete ethnic / social polarization index that showed that the intensity of the conflict, contrary to what was traditionally thought, does not increase the more groups exist, but the closer their distribution is to the existence of two groups of equal size (50%). This idea has had an important scientific repercussion. The original 2002 article and the version published in 2005 in the American Economic Review, have reached the 1245 citations. The work published in the Journal of Development Economic, which analyzes the effect of ethnic polarization on development, received the Elsevier’s Economic and Finance Journals Award for the Most Cited Articles for the 2005-2009 perio9