Gravity for Autism | Teaching Trade Research for a Good Cause

Gravity with Gravitas for Autism

After seeing increased interest in my intensive course on "Trade Policy Analysis with the Structural Gravity Model", on April 21, 2019, I decided that I will teach it for a good cause, and I started my “Gravity with Gravitas for Autism” initiative. The goal is to teach the gravity course until I earn €50,000, which I will donate to support children with autism in my hometown Pleven, Bulgaria. €50,000 may not seem a lot, but will go a long way back home, where a speech therapist session is $12-23 (e.g., in U.S. it is $100-250). My goal is also to raise awareness and to offer access to support for some families who could not afford it. This web site will track my progress and I will use it to thank the people and institutions that have supported me.

I devote this effort to my goddaughter Aleksandra. You, Alex, are simply AMAZING!!!

As of March 2021, I have delivered 60 “gravity for autism” presentations around the globe and I have reached more than 95% of my goal. My plan is to donate the money on June 1, 2021, the International Children's Day.

Faces and Places

My "Gravity with Gravitas for Autism" initiative gave me the opportunity to visit many of my friends and excellent (trade) economists at their home institutions. I also had the chance to meet many talented and ambitious young scholars, and to discuss research with colleagues who I did not know before. I learned about many exciting projects and interesting databases, and I started a few new projects with former coauthors and with cpolleagues who I did not know before. Despite not beeing a big fan of traveling, I very much enjoyed and appreciated the beauty and uniqueness of every place I visited during my early moring runs and while touring these places around with my hosts. Below is a list of the places that I have vistied as part of my "gravity for autism" travels. I am extremely grateful to my kind hosts for the great times and all the woderful memories! Thank You!!!

1st "Gravity for Autism" presentation, March 26-28, 2019, Universtity of Trier, Trier, Germany. My first “Gravity for Autism” presentation was an intensive gravity course at the University of Trier. The students who took the course were interested and smart. I was happy to learn that some of them already used the graity model in their work. I also enjoyed Trier, a beautiful Roman town (also birthplace of Karl Marx). Best of all, I had a great time with my host, good friend and brilliant trade economist, Xenia Matschke, and with her amazing family. Thank you Trier! Thank you Xenia!

2nd and 3rd "Gravity for Autism" presentations, April 1-4, 2019, KU Leuven, Leuven, Belgium. My second and third “Gravity for Autism” presentations were an intensive gravity course and a research seminar. Had fun and stimulating discussions with course participants from KU Leuven, the Europen Commission, and Bank of England. Had the pleasure to meet a great fellow trade economist Mathieu Parenti. My seminar At KU Leuven was on "Gravity and Sanctions". Morning run by the famous Church and the Stella Artois brewery was enjoyable too! I thank my friend and one of Belgium’s finest trade economists, Hylke Vandenbussche, for warm hospitality and a great time!

4th "Gravity for Autism" presentation, April 9-11, 2019, CES ifo Ludwig Maximilian University of Munich, Munich, Germany. They won it all (again): Congrats to FC Bayern! My next "gravity for autism" course was part of the prestigious CES ifo Group lectures at Ludwig Maximilian University of Munich. Particiapnts included a group of excellent Masters and Ph.D students from CES, ifo, and LMU. My friend, Professor Carsten Eckel hosted. In Germany Carsten Eckel is for trade what Franz Beckenbauer is for football. Thanks, "Der Carsten”!

5th "Gravity for Autism" presentation, April 16-20, 2019, Drexel Universtity, Philadelphia, USA. Fifth "gravity for autism" presentation was at a workshop on Sanctions at my home, Drexel, which I co-organized with friends and brilliant trade economists Gabriel Felbermayr and Costas Syropoulos. Many thanks to Prof. Stehr and Dean Jensen for hosting us. Three living legends delivered the keynotes; Thanks to Professors Jonathan Eaton, Cliff Morgan, and Gary Hufbauer! So proud of this timely event on sanctions! Passionate and competent presenters and discussants. Insightful and constructive interdisciplinary interactions. And, yes, a Yoga session for the participants. How cool was that!!

6th "Gravity for Autism" presentation, April 24-25, 2019, University of Goettingen, Goettingen, Germany. Sixth "gravity for autism" presentation was at the University of Goettingen, once home of brilliant mathematician Gauss and of the Grimm Brothers. Presented work on gravity and sanctions. Got great comments and feedback. Had wonderful time and stimulating discussions with great economists Professors Udo Kreickemeier and Inmaculada Martinez Zarzoso. Thanks Udo and the University of Goettingen for your hospitality!

7th "Gravity for Autism" presentation, April 26-27, 2019, De Montfort University, Leicester, United Kingdom. Seventh "gravity for autism" presentation was at De Montfort University, where I talked about gravity and economic sanctions. De Montfort has a great trade group and I had fun, stimulating disucssions, and pleasant interactions with hosts, Drs. Cartwright and Wang. Loved Leicester, home of 2015-16 Premier League Campiions, Leicester City Football Club. At 5000:1 odds against them!!! Best story ever!! RIP Vichai!

8th "Gravity for Autism" presentation, May 6-7, 2019, University of Oxford, Oxford, UK. Eighth "gravity for autism" presentation was at University of Oxford, where, for the first time, I presented our new Structural Trade Openness Index (with Anderson and Larch) based on work that was supported by UNCTAD. Had great time and stimulating discussions with two of world's finest trade economists, Kevin O'Rourke and mentor and friend Peter Neary! Thank you Peter and Kevin! Visit to UK gave me an opportunity to spend time with best hair stylist in London, who happens to be my little sister, Yuliya. Pity I no longer can benefit from her amazing skills, but who needs hair with a body like mine :)

9th "Gravity for Autism" presentation, May 15-16, 2019, ETH and KOF, Zurich, Switzerland. 9th "gravity for autism" talk was at ETH, Zurich. I got excellent fedback on the Structural Trade Openness Index (with Anderson and Larch) and this work is moving forward in good pace. Rare, but still possible, to find colleagues who do deep work across fields, e.g., my host and friend Peter Egger; a brilliant trade guy and a top econometrician, supporting a great group of young and talented economists at ETH! And a fellow fisherman on top of all!! Thanks Peter and ETH!!

10th "Gravity for Autism" presentation, May 17-18, 2019, Vienna University of Economics and Business, Vienna, Austria. My 10th "gravity for autism” talk was a keynote lecture on "Trade Policy with Gravitas" at the 10th Annual Meeting on Economic Geography and International Trade (EGIT). Thanks to Professors Felbermayr, Nitsch, and Suedekum for providing an important public good for the young trade researchers in Europe. Had great discussions with young scholars in the field of international trade, and it was wonderful to see old freinds and co-authors. Thanks to the Department of Economics at Vienna University of Economics and Business and to Prof. Badinger for welcoming us!

11th "Gravity for Autism" presentation, May 24-25, 2019, ifo Institute, Munich, Germany. Eleventh gravity for autism talk was during a joint plenary session with legend P. Neary at the CESifo Global Area Conference. Great keynotes by Treb Allen and A. Bernard. An amazing cast of papers and presenters! The picture that we took to support my autism initiative shows the quality of conference but also that trade guys are good human beings! Many thanks to conference organizer and dear friend, Peter Egger, and to the great team at the ifo Institute!!

12th "Gravity for Autism" presentation, June 2-7, 2019, Hong Kong University of Science and Technology, Hong Kong. 12th "gravity for autism" talk was at Hong Kong University of Science and Technology's boutique trade yearly workshop. Excellent quality, great local experts, young scholars, and researchers from abroad. If you are invited, you shold definitely go!! Thanks to Professors Yao Amber and Edwin Lai for warm hospitality! Looking forward to teach "gravity for autism" at Hong Kong University of Science and Technology in November, 2019!!

13th "Gravity for Autism" presentation, June 11-12, 2019, Università Politecnica delle Marche, Ancona, Italy. 13th "gravity for autism" talk was at the Università Politecnica delle Marche. I taught my intensive gravity course to some very smart and talented students, who had great questions, ideas, and topics for discussion! I thank my friend and top trade and labor/migration economist Alessia Lo Turco for stimulating discussions on the relationships between trade, migration, and globalization, and for great hospitality! Thanks Alessia! Thanks Ancona!

14th "Gravity for Autism" presentation, June 17-18, 2019, U.S. International Trade Commission, Washington DC, USA. I visited U.S. ITC to contribute to the development of the "Gravity Portal", a one-stop software for gravity data, estimations, and general equilibrium analysis (coming soon!). While visiting the U.S. ITC, I also presented our Structural Trade Openness Index. Congratulations and thanks to my host, friend, and great trade economist Dr. Serge Shikher, and to his team for the effort and success in utilizing structural gravity for sound, research-based policy analysis!

15th "Gravity for Autism" presentation, June 19, 2019, World Bank, Washington DC, USA. 15th "gravity for autism" talk was a seminar at the Development Research Group of the World Bank. Our Structural Trade Openness index received excellent reception and I got a series of great comments and suggestions. As always, it was wonderful to see and interact with friends and excellent trade economists Erhan Artuc, Jean Francois Arvis, Paulo Bastos, and Ana Margarida Fernandes. And, of course, it was my honor and distinct pleasure to see and catch up my dear friend, mentor, and co-author Dr. Aaditya Mattoo.

16th "Gravity for Autism" presentation, March 26-28, 2019, Universtity of Trier, Trier, Germany. I taught GE trade analysis with great researchers, good friends, and trade policy experts from Bob Koopman's ERSD group. Wonderful to see smart and ambitious course participants from all over the world learn, work, and have fun together. I am extremely grateful to Dr. Robert Teh who welcomed me to the WTO in 2014. Robert is one of the most humble, thoughtful, and dedicated trade economists I know! Thanks and congratulations, Robert, on an amazing career and all the best for an adventurous retirement!

17th and 18th "Gravity for Autism" presentations were an intensive course and a seminar on gravity and sanctions, June 16-18, 2019, University of Tuebingen, Tuebingen, Germany. Delivered gravity course to smart, curious, and motivated students, including a couple of excellent undergrad students. Enjoyed research discussions with faculty from a strong Economics Department. Highlight was meeting living legend Prof. Willi Kohler. Thanks Willi for your contributions to our field and for mentoring such a great group of students! Thanks friend and great trade economist Dr. Frank Stähler for hosting me!

19th "gravity for autism" presentation, July 25, 2019, University of Munich, Munich, Germany. Delivered a seminar to promote our gravity-based structural trade openness (STO) index. Got excellent questions and feedback on the paper from the economists at the econ department at LMU and from visiting scholars too. Thanks to friends and great trade economists Carsten Eckel and Andrea Ariu for hosting! Good luck to Andrea in his bright future career back in Italy, and looking forward to many great moments at the LMU econ department and at the Alianz Arena with Der Carsten!!

20th "gravity for autism" talk, August 13, “D.A. Tsenov Academy of Economics”, Svishtov, Bulgaria. I visited my alma mater and had productive discussions with President Marchevski, former professors, and young scholars. Tough times for higher education in Bulgaria and, in particular, for smaller and more remote places such as the Tsenov academy. However, I am very hopeful that, with so many smart and ambitious people, better times are coming. Looking forward to my teaching "gravity for autism" course at @TsenovAcademy in October!!

21st "gravity for autism", August 21, The United States Department of Agriculture, Washington D.C., USA. Delivered a presentation on gravity and sanctions and used the opportunity to overview the latest theory and empirical developments in the structural gravity literature. Great to see strong interest in applying structural gravity estimations and general equilibrium modeling for policy analysis in agriculture, including quantifying the impact of SPSs in particular. Looking forward to learn more about trade and agriculture through further discussions and collaborations with agricultural economists. Thanks Shawn Arita for hosting!

22nd "gravity for autism" presentation, August 23, 2019, The United States Trade Representative, Washington D.C., USA. Delivered an overview of the latest theory and empirical developments in the structural gravity literature in front of a number of researchers and policy makers from various departments of the U.S. government as well as to colleagues from the United Kingdom Department for International Trade. Wonderful to see interest in and recognition of structural gravity as the way to go for good policy making when needed the most. Thanks friend and brilliant economist Kari Heerman for organizing my visit!

23rd "Gravity for Autism" presentation, August 26, 2019, U.S. International Trade Commission, Washington DC, USA. I was very happy to deliver my 23rd “Gravity for Autism” presentation at the Office of Economics of the U.S. International Trade Commission. I spoke on gravity and economic sanctions, and received excellent comments and feedback. Very excited about joint work with colleagues from U.S. ITC on developing a new trade and production database (as part of the ITC "Gravity Portal"), which will enable researchers and policy makers to obtain theory-consistent gravity estimates with international and intra-national trade flows. Thanks Drs. Powers and Shikher for warm hospitality!!

24th "Gravity for Autism" presentation, September 1-5, 2019, Arab Monetary Fund, Abu Dhabi, United Arab Emirates. 24th "gravity for autism" presentation was at the Arab Monetary Fund, Abu Dhabi, where I taught general equilibrium analysis with the structural gravity model to a very motivated and impressive group of policy makers (half of whom were women!) Visit to the Arab Monetary Fund at the United Arab Emirates gave me a chance to brush up my Arabic, which I thought was long gone since I studied it in college. But even wihtout Arabic, it was claer that people can speak the gravity language of trade policy! Thanks to the wonderful people at AMF and UAE for warm hospitality!!

25th "Gravity for Autism" presentation, September 13, 2019, Bank of Spain, Madrid, Spain. 25th "gravity for autism" talk was at the Bank of Spain. I presented work on structural gravity in front of a great group of economists and in a building with magnificent architecture and an amazing library!! Had wonderful time with friend and great trade economist Blanca Sanchez-Robles. And, of course, used opportunity to watch some great football in Madrid. Looking forward to teach "gravity for autism" course at Banco De Espana in November!! Thanks to Dr. Timini for hosting me!!

26th "Gravity for Autism" presentation, September 16-18, 2019, The Deutsche Bundesbank, Frankfurt, Germany. My 26th "gravity for autism" presentation was in the form of an intensive gravity course at The Deutsche Bundesbank. Had productive time and stimulating discussions on opportunities to structurally link trade and macro with a great group of participants from The Deutsche Bundesbank and from the European Central Bank. Hamburger and beer with Peter Egger was a welcome bonus. Thanks Dr. Philipp Meinen for inviting me and for hosting!!

27th "Gravity for Autism" presentation, September 19, 2019, The German Institute for Economic Research, Berlin, Germany. My 27th "gravity for autism" talk was at the The German Institute for Economic Research (DIW). Presented structural gravity modeling and ideas for possible links between trade and macro to small group of great macroeconomists. Thanks Dr. Menkhoff and DIW, Berlin for the opportunity!! Another, personal, highlight for me was meeting my childhood friend, and godfather of my boys, Jimmy and my new gorgeous research assistant Philip!

28th "Gravity for Autism" presentation, September 20, 2019, The Kiel Institute for the World Economy, Kiel, Germany. The 28th "gravity for autism" talk was at the Kiel Institute for the World Economy, where I presented joint work on trade imbalances with the President of the Kiel Institute and my dear frined, Professor Dr. Felbermayr. Wonderful to see a great group of smart and ambitious young scholars matched with dedicated senior mentors. A solid foundation for President Felbermayr’s ambitions to make the Kiel Institute a powerhouse in international econ research and consulting. Thanks for hospitality and good luck!!

29th "Gravity for Autism" presentation, September 23-25, 2019, The Organization for Economic Development and Cooperation, Paris, France. The 29th "gravity for autism" presentation was at the Organization for Economic Development and Cooperation, where I taught my intensive structural gravity course to a very competent group of researchers and policy makers from different units at OECD. Learned about new data and generated exciting research ideas. Saw many friends and colleagues. Lunch with friend and a great trade economist, Farid Toubal, was a welcome bonus! Many thanks to wonderful host and friend Dr. Susan Stone!!!

30th "Gravity for Autism" presentation, October 11-13, 2019, Midwest Meetings in International Trade, St. Louis, USA. 30th "gravity for autism" talk at the Midwest Meetings in international trade. Presenting at the Midwest Meetings is always special to me!! This conference has a special place in my heart, and I have no words to thank Ray Riezman for this wonderful public good. Ray has organized 76 (!!) meetings of quality, friendship, inclusion, and support for young trade scholars regardless or race, gender, and geographic location! Few other trade economists have contributed so much for our profession!! You rock Ray!! Thank You!!

31st and 32nd "Gravity for Autism" presentations, October 21-23, Bank of England, London, United Kingdom. 31st and 32nd "gravity for autism" presentations were an intensive structural gravity course and a seminar on trade imbalances at the Bank of England. Had good time and productive discussions on structural links between trade and macro with a great group of economists from the Bank of England! Highlight for me was that a brilliant physicist such as Dr. Arthur Turrell attended and spoke highly of my course. Many thanks to friend and great trade economist Dr. Rebecca Freeman for hosting!!

33rd "Gravity for Autism" presentation, October 28-30, 2019, Universitat Jaume I Castellon, Spain. 33rd "gravity for autism" course was at the Universitat Jaume I Castellon. This was a special experience! I had a truly enjoyable and very productive time among great economists and genuinely wonderful people. I taught, I laughed, I started a new project, and I had tons of fun with great people! I thank my new friends at Universitat Jaume I Castellon, and especially excellent economist and friend Prof. Maite Alguacil Marí for amazing hospitality!

34th "Gravity for Autism" presentation, November 5, 2019, The German Institute of Global and Area Studies, Hamburg, Germany. My 34th "gravity for autism" presentation was a research seminar on quantifying the partial and general equilibrium impact and effectiveness of economic sanctions with the structural gravity model, at the German Institute of Global and Area Studies. I had a very productive and pleasant time interacting with political scientists and discussing opportunities for collaboration. Thanks Christian von Soest and Julia Grauvogel for hospitality!

35th "Gravity for Autism" presentation, November 18-20, 2019, Bank of Spain, Madrid, Spain. The 35th "gravity for autism" presentation was an intensive structural gravity course at the Bank of Spain, where I returned after giving a seminar talk in September. Once again, I had great time and productive discussions on links between trade and macro, currency unions, and regional gravity models. I also started a new project on trade and the gold standard with Dr. Jacopo Timini. Lunch with friend, amazing economist, and wonderful person Dr. Blanca Sanchez-Robles was a highlight, as always! Thanks Jacopo for hosting me!!

36th "Gravity for Autism" presentation, December 8, 2019, International Agricultural Trade Research Consortium, Washington DC, USA. The 36th "gravity for autism" presentation was in a plenary session at the anual meeting of the International Agricultural Trade Research Consortium. Was wonderful to see how well structural gravity was accepted by the agricultural researchers and policy makers. Had many great conversations and generated ideas for several projects, which I hope will materialize soon. I am very grateful to the organizing committee and especially to my friend and briliant economist Dr. Kari Heerman for the invitation to present at this important event! Thank you Kari!

37th "Gravity for Autism" presentation, December 9, 2019, U.S. Environmental Protection Agency, Washington DC, USA. 37th "gravity for autism" presentation was on latest developments in structural gravity modeling and estimation at the U.S. Environmental Protection Agency. Had very stimulating discussions with excellent researchers and policy makers. I see great potential for more work on the links between trade and various environmental outcomes, and I look ofrward to potential collaborations with the great colleagues from EPA. Thanks Dr. Ann Wolverton for hosting me!

38th "Gravity for Autism" presentation, December 10-12, 2019, Gravity Course, Washington DC, USA. 38th "gravity for autism" presentation was an intensive structural gravity course, which I co-taught with friend and great trade economist, Dr. Serge Shikher, in Washington DC. A strong and diverse group of particiapnts in our course, who came from the U.S. Trade Representative, the Heritage Foundation, and even from the Global Affairs department of the Canadian Goverment. Great experience, great questions, great policy insights, great discussions!! Should definitely do it again!!

39th "Gravity for Autism" presentation, January 17, 2020, ETH-KOF, Zurich, Switzerland. 39th "gravity for autism" presentation was at ETH-KOF. As always, a great experience. Received useful feedback on gravity research. More importantly, I spent time with excellent economists and good friends. Wonderful to catch up with Dr. Davide Suverato, a good friend and strong addition to the ETH trade group! Congrats to Dr. Nora Strecker for impactful research and an excellent placement at Dublin! Good luck Nora! Also good luck to Dr. Sophia Ding in her new pursuits!! And, of course, always a privilege and a pleasure to catch up with dear friend Dr. Egger!! Thanks Peter and EHT for warm hospitality and a wonderful time!

40th "Gravity for Autism" presentation, January 30-31, 2020, Internatioal Monetary Fund, Washington DC, USA. My 40th “Gravity for Autism” presentation was an intensive gravity course at the Internatioal Monetary Fund. When the IMF invites someone to cover the latest developments in trade, then you really know that trade is back in fashion:) I had a wondeful time, excellent questions, productive office hours, and very stimulating discussions with high quality particiapnts in the course. I am very grateful to Dr. Anand and the Institute for Capacity development for the invitation. Special thanks to Dr. Hasanov and Ms Berhane for warm hospitality!

41st "Gravity for Autism" presentation, February 10, 2020, Drexel Economics Society, Philadelphia, USA. My 41st “Gravity for Autism” presentation was a short introduction to structural gravity modeling and its application for a group of very talented, smart, and motivated undergraduate students from the Drexel Economics Society at the LeBow College of Business at my home institution, Drexel University. It was great to see the interest these young students had in research. Received excellent and thoughtful questions that demonstrated the high quality of our undergraduate students!

42nd "Gravity for Autism" presentation, February 15, 2020, European Central Bank, Frankfurt, Germany. My 42nd "Gravity for Autism” presentation was a seminar on bilateral trade imbalances modeling with structural gravity at the European Central Bank. You know that your research is important if you can pass security in Frankfurt with an FC Bayern hat!! Got excellent feedback and many questions during my seminar, and had great time at lunch and during individual meetings with a number of excellent economists at ECB. Thanks to friends and great economists Philipp Meinen and Roberta Serafini for warm hospitality!

43rd "Gravity for Autism" presentation, February, 2020, LeBow College of Business, Drexel University, Philadelphia, USA. My 43rd "Gravity for Autism” presentation was at Drexel University. It was a great pleasure to be able to bring home and teach a course that I have delivered around the world with the support of my department, my college, and my university. I was really excited to share my knowledge and experience with good masters students who have very bright careers ahead!! Thanks guys for a great "term of trade":)

44th "Gravity for Autism" presentation, May 21, 2020, III Jornada Investigacion Internacionali- zacion. My 44th "Gravity for Autism” presentation was at the III Jornada Investigacion Internacionalizacion conference, Nebrija University. It was a privilege to deliver the closing keynote. I gave an overview of the developments in structural gravity modeling with an application to bilateral trade imbalances. This was my first online seminar. Felt a bit strange, but I still enjoyed it. Special thanks to excellent economists Jordi Paniagua and Rafa Myro for inviting me.

45th "Gravity for Autism" presentation, July 2020, 2020, RTG. My 45th "Gravity for Autism” presentation was an intensive gravity course that I delivered to the “Regional Disparities and Economic Policy” research group. Wonderful to see a great group of smart and ambitious young scholars matched with great senior mentors under a joint initiative by TU Dortmund, the University of Duisburg-Essen, and the Ruhr-Universität Bochum, with support from German Research Foundation. Special thanks to Sebastian Kunert and Tobias Seidel for hospitality, and good luck!!

46th "Gravity for Autism" presentation, October, 2020, the University of Tokyo. My 46th "Gravity for Autism” presentation was an intensive gravity course that I delivered at the University of Tokyo to a great group of scholars and policy makers including graduate students and faculty from the University of Tokyo and researchers from the Asian Development Bank. Excellent questions, feedback, and productive times. I wish I could deliver this one in person, and I hope that a great trade economist and friend Taiji Furusawa will invite me again to visit in person in the future. Many thanks!!

47th "Gravity for Autism" presentation, November, 2020, the AEEFI. My 47th "Gravity for Autism” presentation was an intensive gravity course that was organized by the Spanish Association of International Economics and Finance with participants from various universities and from the European Commission. This was a great group with a lot of questions and discussion. Another wonderful (productive and enjoyable) experience! Many thanks to my frined and great economist Javier Ordóñez for hosting me and for oranizing the course!!

48th "Gravity for Autism" presentation, November, 2020, the U.S. ITC. My 48th "Gravity for Autism” presentation was opening a session on structural gravity modeling at the U.S. ITC's Virtual Modeling Symposium, where I argued that Structural Gravity is an Estimating CGE (E-CGE) model. Great to see GTAP legends and researchers who use Structural Gravity discuss modeling developments and methods to address important policy questions and new challenges. Check out the U.S. ITC's Gravity Portal at

49th "Gravity for Autism" presentation, December, 2020, the NBER. My 49th "Gravity for Autism” presentation was at the Winter International Trade and Investment (ITI) meetings of the NBER. I was very excited (but also quite nervous) to present brand new work on structural gravity and the extensive margin of trade (with Jim Anderson). Key contribution was the introduction of the "Domestic Extensive Margin (DEM)". Conference was of great quality, as expected, and it was wonderful to see some of the top guys in our field offer constructive advice to the talented younger researchers. Thanks to Steve Redding for including our paper on the program and for his encouragement!

50th "Gravity for Autism" presentation, December, 2020, Kiel. My 50th "Gravity for Autism” presentation was an intensive gravity course at the Advanced Studies Program of the Kiel Institute. Wonderful to see great interest from many colleagues at Kiel, and also from participants from all over the world. A great group, with a lot of questions and stimulating discussions. Thanks to friend and very talented young economist Olivier Godart for inviting me, for oranizing the course, and for running one of world's top programs for graduate studies in international economics!

51st "Gravity for Autism" presentation, December, 2020, DIT. My 51st "Gravity for Autism” talk was a presentation of partial and general equilibrium structural gravity modeling at the Department for International Trade of the United Kingdom. Excellent questions and very stimulating discussion with smart and motivated policy makers and academic colleagues. The structural gravity model is indeed very well suited to address a number of relevant and important policy questions. While, personally, I would have preferred a world without BREXIT, I also see that this major event motivated us to think harder about the tools we have to characterize it and its consequences.

52nd "Gravity for Autism" presentation, November, 2020, LMU, Munich. My 52nd "Gravity for Autism” presentation was an intensive gravity course, which I taught to Master Students at LMU Munich. The group was small, but the students were extremely motivated and very good. Not only they understood and mastered the material but, in a short period of time, they were able to effectively apply it to study the effects of current and important policy events including the US-China trade war, BREXIT, the trade trade relationships between Canada and U.S., etc. Seeing the students enjoy learning was a very rewarding experience. I thank friend and brilliant trade econmist "Der Carsten Eckel" for the opportunity!

53rd "Gravity for Autism" presentation, December, 2020, ESCAP and ARTNeT. My 53rd "Gravity for Autism” presentation was an intensive gravity course, which was organized by the United Nations ESCAP and ARTNeT. Was very happy to see great interest in the course and that the participants found it useful. I enjoyed stimulating discussions with some CGE modelrs who saw the benefits of combining structural gravity methods with their work. I am very grateful to Drs. Mia Mikic and Alex Kravchenko for the opportunity and to all participants for their engagement in the course!!

54th "Gravity for Autism" presentation, January 5, 2021, ASSA. My 54th "Gravity for Autism” talk was at the annual meeting of the American Economic Association. I presented joint work with Gabriel Felbermayr. We show that the structural gravity model is well suited to predict bilateral trade imbalances. Once again, the multilateral restittances won the gold medal! Very grateful to the International Economics and Finance Society for the invitation to present in this great session, and especially to Matt Cole for the swift handling of the organization matters.

55th "Gravity for Autism" presentation, January 20, 2021, Paris. My 55th "Gravity for Autism” presentation was a lecture at the Université Paris-Dauphine-PSL. I taught students how to perfrom general equilibrium analysis with the structural gravity model. Omitting the GE links may lead to very significant (e.g., 20 to 50 percent) deviations from the true effects of trade and other policies. Enjoyed interactions and discussions with very smart and motivated master students and colleagues. Many thanks to my friend and brilliant trade economist Farid Toubal for the opportunity!!

56th "Gravity for Autism" presentation, February 22, 2021, Boston College. My 56th “Gravity for Autism” presentation was a seminar at my alma mater, Boston College. I presented joint work with friend and co-author Gabriel Felbermayr in which we uncover a new property of the structural multilateral resistances as asymmetric trade costs. The highlight of this presentation was when the father of structural gravity, and a mentor and dear friend, Jim Anderson, said that he enjoyed learning from me about this new property of the multilateral resistances. Thanks, Jim and BC!!

57th "Gravity for Autism" presentation, March 10, 2021, World Bank. My 57th “Gravity for Autism” presentation was a research seminar at the World Bank, where I presented new work on the impact of state aid on trade. My co-authors Mario Larch, Serge Shikher, Jose Signoret and I propose a structural estimation framework that decomposes the effects of production subsidies on trade and production into direct, indirect and general equilibrium effects. Using new data by the World Bank, we find evidence that production subsidies promote trade disproportionately.

58th "Gravity for Autism" presentation, March 12, 2021, Drexel University. My 58th “Gravity for Autism” presentation was a graduate course on trade policy with structural gravity at home, the LeBow College of Business at Drexel University. I was very excited to bring the course home and to share the experience that I have collected with our own master students. I am very grateful for the support of the School of Economics, the LeBow College of Business and Drexel University for their constant support and I wish our graduate students good luck in their future careers!

59th "Gravity for Autism" presentation, March 22, 2021, Higher School of Economics, Moscow, Russia.. My 59th “Gravity for Autism” presentation was a seminar on structural gravity and bilateral trade imbalances. It was wonderful to catch up with friend and excellent economist Alex Tarasov, and I very much enjoyed a number of productive discussions with colleagues from HSE. I learned about some new and exciting research that is related to my work, and I look forward to continue these conversations. Thanks HSE! And thanks and good luck Alex in your new endeavors!

60th "Gravity for Autism" presentation, March 25, 2021, Vienna University of Economics and Business. My 60th “Gravity for Autism” presentation was a seminar, jointly organized by the Vienna Institute for International Economic Studies and the Centre of Competence in International Economics. It was great to see interest in my joint work on trade imbalances with Felbermayr and catch up with friends. Received excellent questions and feedback. Thanks, wiiw, FIW Mahdi Ghodsi and Birgit Buschbom for the invitation and for the hospitality!

A Team Effort

I have been blessed to be surrounded by a wonderful family and so many good friends and amazing people. I am so grateful for your support!!

Most of all, I thank my wonderful family. I am extremely fortunate to have you: Aneliya--the most gorgeous and kind woman, who has been supporting me for more then sixteen years since our engagement; Valentin-- the best footballer among mathematicians and vice versa; and Ivan--the owner of the biggest and bravest heart on earth! Thanks! I love you! Not spending time with you is the biggest cost that I pay while traveling to teach “gravity for autism”. I am very grateful and proud of you for supporting me and I will make every minute together count.

I thank my Mom, Dr. Snezhina Todorova, for being the best mother one could have! You have always been an inspiration and a role model to me. Thanks for your support and encouragement, for being the best pediatrician, and for helping with my autism initiative! Love you, Mom!!

My "gravity for autism" travels gave me a chance to spend time with H.R.H. Princess Maria Luisa of Bulgaria. I was honored and humbled. Thank you, Your Highness for all that you do for Bulgaria, and for your encouragement & support for my "gravity for autism" initiative.

My “gravity for autism” initiative is what my home, Drexel University, is all about: cutting-edge research; dedication to teaching; and leadership in civic engagement. Thanks Drexel, President Fry, Provost Jensen, Dean Madan, and Prof. Stehr for your support.

Sincere gratitude to Dr. Diana Robins and her team at the A.J. Drexel Autism Institute for their research on autism and for sharing the M-CHAT - one of the most widely-used tools for autism diagnostics, which is already successfully implemented by Dr. Todorova in my home town in Bulgaria.

Special thanks to my coauthors and dear friends Professors James Anderson, Mario Larch, and Costas Syropoulos for your support for my "gravity for gravitas" initiative. Interacting with, learning from, and working with you has been one of the most pleasant aspects of my "job". Pic on left is with Drs. Costas and Heidi Syropoulos while testing the strength and persistence of our “love of variety’’ for locally brewed Philly beer.

Thanks Stata Corp. for providing free-of-charge Stata 16 licenses for all my "gravity for autism" courses! I have found Stata cheat sheets very useful for teaching my gravity course.

Thanks to my colleagues and friends Drs. Robert Koopman, Roberta Piermartini, and Robert Teh at the World Trade Organization for giving me the opportunity to write the "Advanced Guide for Trade Policy Analysis with Gravity", and to teach gravity to many policy makers from developing countries.

I am grateful to colleagues and friends Dr. Bill Powers and Serge Shikher at the United States International Trade Commission for allowing me to contribute to th development of the ITC's "Gravity Portal", a one-stop software for gravity data, estimations, and general equilibrium analysis.

I thank Lee Malone, an extremely talented young photographer, who created my “gravity for autism” logo and also Alex’s pictures with the flags of the countries where I presented. Thanks, Lee, for your great work and big heart! Check out Lee’s amazing work at

I also thank my good friend Stefan Georgiev for his constant support with and ideas for my web site. Thanks Stefko, for being the great guy that you are, for your professionalism, kind soul, and for always being ready to help! Check out Stefko’s great work at

I was honored to be selected on the Fulbright Specialist Roster in 2019, and in 2020 a project to teach “gravity for autism” in Bulgaria was approved by the U.S. Sate Department. Cannot wait for travel to resume, so I can give back to my alma mater, the "D.A. Tzenov" Academy of Economics, Svishtov.

I am very grateful to the Drexel University’s Office for Global Engagement for supporting my gravity for autism initiative with an International Experience Funding Award, which allowed me to deliver some of my “gravity for autism” presentations.