Saturday, September 20, 2014

Boots on the ground in studying cities: Street View or data analysis are never enough.

When I wrote you about using a close-up aerial view, I was making a suggestion. Not a demand. I thought it helped me understand where I was. And the birdseye view in Bing is even more helpful.

My goal is to give you the knowledge and skills to understand places in context. Maps, frontal views and other views you make by being there (over a fence, adjacent places,...), Street View, aerial and birdseye views, all help. What you are trying to do is to become fluent in all these media and methods.

I always have other professors asking me why I send you to places, since Street View has done it. But in fact Street View is partial, has no sense of the life of a place, may well be outdated, etc. More generally, you really have to go look and be there, in the city, if you want to understand what to do--whether you are a developer, a planner, etc. The deluge of visual data we now have is no substitute for boots on the ground, so to speak. Similarly, when you learn to do statistical analysis of a data set as in the Census or a survey, you still have to ask if it makes sense in terms of the people you are studying, and it is vital to do fieldwork and interviews to see if your analysis has ground truth (as they say in aerial surveillance). Good regression coefficients may be statistically nice, but your model may have missed important stuff. A good R-squared is no substitute.  As someone once said to me, about rats in psychology, you've got to talk to your rats.

Friday, September 19, 2014

Focused Paragraphs, Questions: What's the Big Idea?

In reading over students' discussion of others' work, I have some suggestions that may be more generally useful.

1. You have good ideas but they are often buried by lots of stuff. If you write a paragraph, make sure you put a topic sentence at its beginning that states the main point--which you may only discover after writing most of the paragraph.

2. The same for the questions you may ask at a seminar. You may be thinking "out loud" as you write the questions, but after doing that, underline the main question or questions. They need to be sharp and not very long. You can put all he context and qualifiers after the questions, or rescue the main question from the middle of your question paragraph.
3. What this all says is that you want to examine your work for the main points. So if you have written a paper, you want to then write an introduction that says the main ideas in a sensible way. Put differently, could a busy person get your points by reading the first sentence of your section or paragraph, etc. Is the introductory two pages sufficient for them to figure out your conclusions etc. 

What you want to do is not point what's wrong with work, so much as figure out what the speaker should do next. Or even better, what should be her main contribution? (If the paper is truly vulnerable, think about how to make it stronger.)

One other point. At the recent Health Economists conference here in June, there was an opening session of Peter Orszag and Casey Mulligan. Mulligan had just launched a book on how the responses to the Great Recession actually harmed economic growth. Orszag said that if we want to get at the 1/3 of health expenditures that are wasted we needed not only deal with supply, we'd have to deal with insurance. Very different approaches: Mulligan examined things as a first-rate economist. Orszag examined things in terms of what you needed to do to tackle a big problem. Neither was much moved by the other--since Mulligan is concerned with getting the numbers right, and Orszag was concerned about transformative change and politics. They were not talking past each other, they were talking about different things.

Tuesday, September 16, 2014

Asking for Help. Graduate Student and Post-Doc. It not "internalization of the aggressor," but taking care of your students as you wish you had been cared for.

The research literature suggests that a graduate advisor or a postdoctoral advisor can make a big difference in the training of a student and beginning researcher. Some advisors are proactive, others less available, others impossible.

But you have to ask for help, be persistent, and not be sidelined. If your advisor proves unhelpful, you need to find another, pronto! If you don't understand something, or need to learn something which you believe everyone knows or that should be easy to learn, but it is not for you, find someone to help you. If people put you off, keep looking.

Some advisors take it upon themselves to train people, others may leave it to postdocs to do the training of the student. But postdocs are so involved with their own survival and careers, they may be of little use. You have to persist. You need to make lists of what you don't understand, make sure you are not a tool in a research program, but are being educated.

Usually there is lots more to learn after you have completed your coursework and exams. And that is true after your PhD and even later. Your advisor should in effect be demanding, making sure you have learned. But many practice sink-or-swim, figuring it was good enough for them, so it will be good enough for you ("internalization of the aggressor"). Nonsense.

If you are stuck in a bad place, it's almost always better for the long term to get out of it if you can find another landing place, even at a different institution. The cost of not doing so may well impact your future career, and your sense of your competence.

Of course, you could decide this is not for you. That's a different question. Here we are concerned with the education and training and discipline you can learn from an experienced teacher. And it is not a matter of independence from your advisor--it's a matter of having a supportive person watching out for you.

Some are independent souls, able to do it all on their own. I know of very few.

As for advisors--you have to be proactive, work with your students and postdocs, be specific and demanding, and be open to mismatching and mistaken placements. It's simple: would you want you children being treated as you treat your students?

Saturday, September 13, 2014

By the fall of 1966, I was prepared to abandon mathematics and to turn to some other life, a first step being a year or two in Turkey with my wife and children, as a prelude to an existence whose exact form was undetermined.

 Robert Langlands is a distinguished mathematician and here he is describing a mathematically low-point in his life.

I, myself, was searching for a general notion and had despaired. By the fall of 1966, I was prepared to abandon mathematics and to turn to some other life, a first step being a year or two in Turkey with my wife and children, as a prelude to an existence whose exact form was undetermined. I, who had never been anywhere outside of English-speaking North America, returned to the study of Russian and began the study of Turkish, frivolously daydreaming of a trip to Turkey --- with wife and four small children --- through the Balkans or through the Caucasus. In the end we arrived in Ankara by a more banal route. Even with the Russian and Turkish, I had time to spare and began, as an idle amusement, to calculate the constant term of the Eisenstein series for various rank-one groups. I had, curiously enough, never done this before. I discovered rather quickly a regularity of which I had been unaware. It was described in the lectures delivered at Yale some months later and included in Part 3 of this collection. The constant term, or rather the second part of the constant term, the part that expresses the functional equation was there denoted M(s) and given at the very end of §5 as a product that I write here as
r being a small integer, often 1, and ai being a positive number. Suppose, in order not to confuse the explanations, that r is 1. The issues arising in the general case are treated in the references. It is the relation expressed by (1) that suggests and allows the passage from the theory of Eisenstein series to a general notion of automorphic L-function that can accommodate not only a non-abelian generalization of class-field theory but also, as it turned out, both functoriality and reciprocity. It was the key to the suggestions in the Weil letter. The Yale notes were written a long time ago and were hardly exemplary expositions. I have no desire at the moment to recall the details or to improve their presentation --- the reader is encouraged to consult the writings of Shahidi, for example the book Eisenstein series and automorphic L-functions --- but there are a number of points to which I would like to draw attention, and it is more convenient to refer to my own notes. I repeat, first of all, that (1) refers to rank-one parabolic subgroups, thus to Eisenstein series arising from maximal proper parabolic subgroups, so that it does not require the second or the third steps and is analytically at the level of Selberg's original arguments.

Thursday, September 4, 2014

Limits vs. Going over the Top: Beating the Odds by Grit and Perseverance

 On a Chipotle bag is Sheri Fink (PhD, MD) on the case against limits. She wrote the book on the New Orleans Hospital during Katrina.  Her point here is that much of our inquiry about rationing ignores the fact that people want to do it all, and some are willing to try.

"Then I think about that innovative, can-do attitude. That refusal to accept limits, quintessentially American. A student nurse says: on my ward we won’t give up on anyone. It is unrealistic. It is exactly what might save us."

Similarly, it may well matter that you not believe the odds and try to beat them, say as an entrepreneur.