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Economic Research: Creating, Writing, Presenting
Maarten C.W. Janssen
Aim, Background of the Course
• Assumption 1: You want to become known for your research in the international scene
• Assumption 2: You have the necessary skills and knowledge to do research in your field
• But this is by far not enough (only 50% of work)
• You have to do your own marketing– Competition for attention
• Backward induction
You can be very smart, but…
• You are (very) unlikely to be in the position to create a new line of research
• Research is building on others, linking to others, get feedback from others– Network is important, internally in the school
(among PhD students), externally in your field– Collaboration can be inspiring– Being recognized is about how you connect to
others; others will help you by giving their feedback
What is my message and for who?• Why is my work important?– Do I contribute to existing literature? If so, what? And
why is this literature important?– Do I have a methodological contribution? What are
the (potential) applications?– Do I contribute to an understanding of some real
world issues? What other contributions are there? Are they complementary? Is my contributions better, more plausible, why?
• Which people would be most interested in my work? Do I have different lessons for different audiences?
Lessons to be Learnt from JET editorial report #1
• Does my paper really matter?– There is some literature (quality chosen, price signals
quality?) Is my modeling more appropriate?• What is wrong with previous papers? Do I have
evidence of this?• If it is a theory paper, it should have useful
machinery• Presentation is way too awkward– Equations too dense– Not adequate notation– What is a real result, what just some technical lemma?
Creating• Start naively:
– I have a data set– I saw some paper and checked whether results hold under
alternative assumption (robust)– I was struck with a newspaper article, everyday life
• In the US without US adaptor• Taxi driver does not want to take you• Sitting with wife in the car, to buy gasoline or not?• Adverse selection is not a problem (bachelor student)
• Anything is good, but soon you have to ask: what is my message and for who?– You may change the answer all the time, but you need to know
where you intend to go to direct your research efforts– Remain open to alternative messages, interpretations– Read nontechnical, non economic literature; institutional detail
• Can I publish about Russian economy in international journals?
During research
• Think about what are the possible outcomes?– Theoretical research: Any equilibrium has certain
properties? Or, there is an equilibrium with certain properties?
– Empirical research: economic and statistical (in)significance? • Very different things
– Is any outcome interesting? But for different reasons?
• Expected cost/benefit analysis
Start simple• Theoretical research: what is the simplest model that
you can think of that captures the phenomenon you want address?– What is essence?– US Electricity adaptor– Adverse selection
• Empirical research: look at the data, do also simple descriptive statistics.
• Helps enormously to focus main message, get it across.• Research is then mainly a robustness check (helping
you to sharpen and deepen main results)– Adverse selection
What if you get the opposite result of what you expected?
• Ask yourself always why you get a certain result? – Can I explain the result without going into technical
details?– Is the result correct? (often, when you cannot explain
there is a mistake—simulations?)– If so, what causes this unexpected result?
• Is it an unimportant assumption that can be replaced by another one?
• Or does my intuitive result only hold under some conditions (and can I understand these conditions intuitively)
– Learn from intermediate results you get, relate back to main message? Should it be reformulated?
• What are the crucial assumptions, what not?
Role of Simulations, Numerical results
• Depend on area – Computational heavy (dynamic macro, or not)
• But generally, – It is not considered as a substitute for a proof
• It is nevertheless increasingly useful– Plot f(x) < 0, but not for f(x; α,β,γ) < 0– Get an idea whether your intuitive result is correct or whether there are
counterexamples– Aid understanding by giving a flavour of magnitude of effect (economic
significance)– Draw pictures– Check robustness (where model is analytically untractable)
• Be open and honest about which results are analytic and which you obtained with simulations– Do not hide unclear numerical analysis in proof in appendix, (especially
not if you do not have clear intuitive explanation for your claim)
Read, but not too much• You have to be able to relate what you have been doing to
what others have done– You have to know that– Especially in an oral presentation you cannot hide behind others
“this is a crazy assumption, but others also make it”• Reading too much may prevent you to be original (as you
tend to copy things you have read)• People do not want to hear (or read) endless literature
review (Murayev; Boulatov, finance presentation)• Read at different stages differently
– In beginning: did someone do what I intend to do– Later: how exactly do I differ? Which crucial assumptions, timing
of events? What if I incorporate some of their assumption in my model?
• You should be able to defend your crucial departures from the literature – Yankelevich presentation: behaviour of shoppers
Talking, talking, talking
• You only understand your own research when you can explain it.
• When you have to explain to someone else, you have to distinguish between main and side issues.
• Often prevents loopholes in argumentation.• Talk during lunch, come to the office• Organize your own (brown bag) PhD research
seminars where you discuss among each other!
Presenting, Writing
• Rule 1: (almost) never follow the line of research that lead to the results
• Rule 2: be enthousiastic about your results– If you say “I did some exercise and this is the
result”…… you do not motivate people to pay attention to you.
• Be honest: if there is a critical assumption, you cannot get rid of, or if you do not know what happens if you change it, say so – But give it a positive turn (future research, I would be
a hero in this branch of literature if I could)
Presenting, Writing
• Learn from others– Why did I like this paper, presentation?– Why did I get board?– How do I read other people’s work?– When do I loose concentration during a
presentation?
• Develop your own style
People’s time span of attention
• 1 minute: people want to know whether it is worthwhile to listen, read further– What is the topic, what can they gain?– Title (abstract) is very important
• 5-10 minutes: which main results do you have, what do you add to what is known– Introduction should contain this
• 1-2 hours: get into more details, how do you get these results, which methodology, which data, model?
Titles• Do they attract attention?• Convey topic of the paper, main result?• Examples:– Going where the Ad Leads you– Do Auctions Select Efficient Firms?– Can we Rationally Learn to Coordinate?– Non-exclusive Conventions and Social Coordination– Signaling Quality Through Prices under Oligopoly
• Job market papers at HSE– Can you trust your broker?
• If you pose a question, – It should be attracting attention– You should answer it clearly, and it should have element of
surprise
Introductions I• Most critical part of a paper, usually rejection is based
on Introduction only• Requires writing, rewriting, ….., 5-6 times• How to start, where to explain your insights– Get as quickly as possible to your results– Start with the most key papers and what they lack if you
have a pure theory, methodology contribution– Start with describing real world issue and what you aid in
our understanding of it (do literature review then afterwards, and sometimes even before the conclusions—if your breakthrough can only be really described after you have presented it)
– Adverse selection paper as example
Introductions II• Describe main features of your set-up concisely• Describe your main results– Why they are interesting (adds to methodology, adds to
understanding)?– Why you get it (you should be able to explain the main
mechanism(s), not I worked hard to crack the math puzzle and this is the answer
– Only a few readers will ever go through all your proofs (even referees seldom do): you have to write so that people understand it and believe result once you have made them think about it.
• Relate to several literatures (if possible), to show breadth.
What comes next?
• Model?– Often yes, but try to be creative:– A simple 2x2 example capturing the main features of
paper (Kandori, Malaith, Rob, 1993 Ectrica; 2010 EJ paper)?
– Extensive Literature Review?– Description Institutional Context or Data?
• Literature review should not be a list of short statements about other papers.– Make a story with your paper and results as the central
theme. Start with fundamental papers, say how other papers have built on it and how you continue (or break with that line)
Once you get to a formal model
• Take the lessons of Thompson to heart• (Here is one example where an oral presentation is
different from a written one)• Notation
– Follow existing literature as much as possible (f = ma)– Use natural symbols– Is notation essential (if used only once or twice……)
• Explain assumptions and their interpretation (are they usually met? What is their role ….)– And if you can do without the word assumption, it is better.– We assume there are two periods. In each of these periods,
individuals are assumed to work and we introduce the assumption that the utility function is concave…. Or
– Consider a two-period economy where individuals have a concave utility function and work in every period.
Present Formal Results• In main body of the text, people want to see things that
stick out (propositions, hypotheses, results, statements)– Indicate them as such (with open space)
• Take care these are very precisely formulated• Make sure that they correspond to the main results of the
paper as explained in the Intro. Déjà vu, but in a more formalized manner– I have seen main results being presented somewhere in a
footnote (and vice versa)• And spend at last one paragraph introducing the
propositions and (after stating them) explaining them.• Think about proofs in appendix, properly bordered in
the text, or informally presented as part of the flow of the text (what is audience, what is purpose of proof?)