Email is Evil

February 20, 2005

Let me apologize in advance if my email(s) have wasted your time. If so, you have every right to be offended. I am trying very hard not to burden you with electronic clutter. So from now on, all email correspondence with me is likely to be highly probabilistic.

I made just one New Year resolution this January. I decided to slowly eradicate my use of email to the extent possible.

Since then, I have kept my counsel and assiduously refrained from sending an email unless it was absolutely necessary. I have been sending many emails to myself, reminders of various things to do, and so far, this seems to be the best use of email – as a portable to do list. I can access it from anywhere. But for communicating, I use it very little. I have been picking up the phone and calling a lot more, and its much more efficient.

Here are some reasons why I got fed up of email:

  1. It is a huge distraction. Every time an email comes in, it interrupts my train of thought. This is not good for my kind of work, for research requires immersion, and getting into the zone. Email makes this impossible.

  2. Email fools you into a false sense of productivity. Many of us work 8-hour days and spend 2-3 hours tending email. That is a horrific waste of time, yet, we all feel even more productive on the days we spent more than the average time on email. Remember the old days when we actually worked all 8 hours? And did not have the luxury to take 3 hours off for email? Since I reduced my email interaction, I have been much more productive.

  3. Email brings in a lot of freeloaders. I get at least one email a week from a student on some other campus asking me some long, detailed and convoluted question, expecting me to respond in detail, so that my answer may be cut and pasted to form a major portion of a term paper. No one would do anything like this if it were not free. Even though I know that no professor would respond to an unethical request such as this, it still results in disturbing one’s mood and leading to loss of productivity. Thus what is a free interaction from one viewpoint, turns out to be very costly from the other.

  4. The length of an email is inversely proportional to its value. This I think comes from the fact that the people with the most time to waste, will do so. Those who are busy and pressed for time, tend also to respect others’ time as well. I find it best when I get a short 3-4 line email focused on what is needed. Anything more seems better done on the phone.

  5. What goes around comes around: I have noticed that the more email I send, the more I receive. There are weeks when I just have not felt like sending email, and the inflow also seems to trickle to a smaller flow. So, if everyone only used email when absolutely essential, we would all be better off.

  6. Nothing goes wrong if email is responded to at the pace of snail mail. Try it, you will see. In fact, I find that the quality of my email correspondence has gone up as I have begun to reply when I felt more like attending to it, rather than doing so instantly.

  7. Email is not an integral part of my job. A research career has this huge plus – there is no real time need to respond to email. I can well understand people like lawyers, accountants, businessmen, corporate managers needing email to get their jobs done; they need perpetual connectivity. Well, thankfully, I do not. At teaching time, sure, students will email with questions, but immediate response only seems to get another, and does not foster learning or problem resolution. There seems to be some happy medium response time within which, left to his or her own devices, students will find the solution themselves. And this leads to deeper learning. It is very tempting to reply at once, especially since you feel gratified at having a good turnaround time, but it does not always help the learning process. So many times, I have been unable to respond in time, pressed by other demands, and in the interim, I get another email from the same student asking me to disregard the previous email for he/she has sorted out the quandary. Yet, there is a loss of student time, two wasted emails. To be fair, students are very respectful of my time, and maybe, should be more respectful of their own!

  8. Email ruins your writing style. It has a perverse code of its own. It would make an English schoolteacher cringe. It makes people bad readers and bad writers.

  9. Email steals vital downtime. Before, when we had a quiet moment we savored it. Remember transiting in airports, reading quietly, staring out the window? Now those days are gone. Now everyone in transit is rushing to check his or her emails. No wonder everyone is so stressed out; they do not get that much needed downtime anymore. “Oh, I have 5 minutes to spare, let me check my email – I feel so cool and accomplished.” Its the new treadmill.

  10. It’s become an excuse to avoid hard work. A recent study reported in the New York Times showed that people use email as an excuse to avoid hard tasks. If one is having a hard time concentrating on a focused task, a natural instinct is – “let me check my email” – so, please stop that, you know you can always find an email that will take you away from your main task. Is it any wonder that we get less done nowadays?

  11. I make mistakes in my email correspondence all the time. I am not sure why this is. One, it might be that in my hurry to clear the mail from my in box, I just “deal with it” and make an error in my impatience. Two, it may be that I know I can always send a correction just as quickly as I did the mistake. Three, it may just be that the medium fosters poor clarity of thought. Of these, my money is on the last one.

  12. Email is hard-to-jettison baggage. It keeps coming back. There are too many people who simply love replying with a couple of words, but attaching all the previous thirty or so emails. This back and forth correspondence has gone on long enough so that we remember all the past correspondence anyway. But no, we need to send it around yet one more time! There needs to be some discipline here. Yet Google is not institutionalizing the problem with its filing of “conversations” – who are they trying to fool? Is email a conversation? If so, then I have been talking to some people for months.

I now only read my email when I have to open it to send an important message to someone. Even reminder emails to myself do not need me to open my email. Since I am a Mac/Linux user, I can send myself an email from the command line without opening my email client. Because I know, once I open the mailbox, even Pandora could not have designed the trap better.

Actually, none of this is new. There are many others who, engaged in creative pursuits, have realized how detrimental email is. Donald Knuth has stopped using email altogether. See his web page for a honest admission of the time sink he needed to extricate himself from: knuth/email.html

Neal Stephenson writes of the ill that follows from the use of electronic interruptions. He quotes Linda Stone, who has coined this as the problem of “continuous partial attention” which makes giving any one thing the full attention it deserves near

So, use email as one would use snail mail – only when necessary, and only when you know it will not be a waste of someone else’s time.

My biggest fear is that email is making the world superficially smaller, and draining all quality out of interpersonal communication. Now, instead of calling and really talking to someone, we shoot off an email and assuage our guilt by convincing ourselves we had a meaningful interaction.

I think I would rather not participate in this charade.


Math Code

February 13, 2005

Math coding is the writing of software to implement a piece of mathematics.

Being extremely fond of writing software but not being dependent on it for a living makes it truly enjoyable. Every now and then I find myself the victim of bad design, always self-inflicted. Like recently, I wrote a piece of code for posting the solution to a homework problem, and did a pretty hasty hack job, so much so that while still being a pretty nice piece of programming, it lacked the clean, readable form that tells you instantly when it is done, and done well. And for that reason, more than any other, it had a bug, and maybe more. I have still to debug this, and will do so I know. But its hard to go back and fix something that does not deserve it. Trash is trash, who wants to take it from bad trash to good trash?

Good code (especially that with a mathematical purpose) needs to be short. It should be as readable as the underlying mathematics. Really good implementation code is so good that reading it is sufficient, you do not need to read the math; superb code is even better – after reading it, it improves your understanding of the math.

How do you write good code that implements mathematics? So good that you need almost no comments? There is but one way, in my opinion, make it really concise. This will also make the code simple and efficient. Take everything out that is superfluous. Here is a quote, which is spot on, simple and elegant: “A designer knows that he has achieved the perfect design not when there is nothing left to add, but when there is nothing left to take away” – Antoine de St-Expurey.

Here are some rules that I have learnt from experience over the years.

  1. Math code can be very different in different languages. Choose the language well. The good news is that you do not need to know many languages well to choose one, and the bad news is that some languages are much better than others. Some like Perl, are not meant for math code, its syntax makes it hard to later revisit the math. Python is much better but is also not really suited for this. C and Java are pretty good. But best are packages like Matlab, Octave, Mathematica that have grown into full-blown programming languages. I find VBA programming in Excel very conducive to writing good math code- using the macro interfaced with spreadsheet offers tricks and hacks (all elegant) that are unavailable in other environments.

  2. You can write really good math code without knowing heaps of features of the chosen language. Writing good math code is a matter of style, not that of the richness of language features. I hardly know a lot of language features, and tend to find them when needed. That is why I enjoy reading student written code – there is always something in the programming language that I am introduced to.

  3. Develop a personal style. It is really important when writing math code. I have one, and I know it, it suits me well. It took me a long time to feel it. I am afraid I cannot tell you how to do this, its personal. All I know is you will not find it by looking over someone else’s shoulder. Just write a lot of code, and if you are not enjoying it, then your style is off. You will know when the style fits.

  4. Keep trashing the code until it looks good. Its got to be pretty. Don’t get locked into the first version you write, ending up with some variant of your initial draft. This sounds like the same advice given to young writers of prose, and in many ways, yes, it is the same thing. But math code is different – if you buy into to the idea of keeping it short, your final product is about 1-2 pages of code. With that in mind, it is not in the least bit painful throwing it away and starting again. Do this often, and soon, you find your first versions are pretty good already. Once it feels good, go back and take out all the unnecessary stuff. The usual programming instinct is to tidy up by adding comments. Good math code does not need it. Whoever wants to read it needs to know the math anyway, and if you write it clean and neat (and concise) it will be easy to read. Math is truth, and truths are meant to be self-evident.

  5. If the code is unwieldy, runs slow, is hard to read, and fails to improve after a few writing iterations, there is something wrong with the math or the numerical recipe you came up with. Many times, in sheer frustration, or from absolute need, I have had to go back and revisit the math, and lo and behold, there pops up a terrific new way of defaling with the whole problem. Work it out nicely, reprogram and voila, it works great. Never be reticent about revisiting your mathematical analysis. I am never happy with my theoretical work until I have the model coded and running, running really well. Often running well in two separate languages. Good math works well. Write once, run anywhere.

There is something special about writing code to implement math. Its a different mind set, a varied skill, and not easy to develop. Most mathematicians will never be good at it, despite knowing the math well, which seems like it must be a major prerequisite. Physicists are great at it. So there is something about training. Engineers should be, but are most often not good at it. There is an essential attitude – something about trying to mimic the real world in software that makes for writing good code, and that is something physicists do well. So do people with computer-science degrees. And some in Applied Math.

What I like about math coding is that I always deeply enhance my understanding of the math through the process of programming it. Its like a wheel of understanding, it comes round to feed itself through the code. Most of all, it enhances my passion for the math to see it really work.

Mathematics and Finance

February 2, 2005

There is a serious lacking in the undergraduate ability to engage in conceptual work involving mathematical logic. After getting disappointing results in two recent quizzes on quantitative material, I am faced with a quandary – should I just not proceed further and spend a few classes instructing everyone on all the high-school mathematics that they should know and just plain forgot? Or is it too far down the road for this now?

The problem lies not in an absence of prior mathematics instruction. It lies in the approach to mathematics. Math tends to be taught as a set of rules and is usually taught by example, and not from first principles. This is like teaching a tourist the most popular phrases in a language before a trip, leaving only a rudimentary knowledge of the language. Such knowledge is not enough to “speak” and “reason” with, yet is enough to “get by” with.

Unless mathematics and logic become first languages for students, subjects like Finance will always remain out of reach. No math facility implies no finance fluency. Doing finance is speaking math.

I believe there are positive externalities too. Analytic thinking develops well with subjects like math. This is an invaluable skill even with non-quant subjects like strategy and policy. Math immersion brings conceptual clarity across the board.

Paul Graham goes so far as to emphasize that the only way to keep all life and academic options open over the long run is to make math a priority. Given he choice he suggests always choosing to major in math over economics. Doing math allows one to later do economics as well, but never vice versa. For a superb essay on these matters, see

Its never too late to go after mathematical training. I know many friends who came to math late in academic life (myself included). Initial progress is slow, but then the pace quickens. Its a subject where some immersion is required before everything begins to fall in place. There is a reasonable period of waiting, and then mathematical maturity begins to arrive. Its a great feeling.

Long run, the problem needs to be stemmed at the high school stage. It is here that the abhorrence of math develops. The subject is presented in a dull, dry manner. It is taught in a rule-based way, and very little appreciation for the physical nature of mathematics is conveyed to the student. By the time the student arrives in college, any positive inclination (barring those always serious students) to the subject is stolen away.

An additional problem is that no societal incentives exist that would attract students to math in the U.S. Mathematicians are looked down upon, they are badly paid, and even ostracized by big-talking bullshitters. In the corporate sector, the math-skilled are relegated to factories, back-offices and research shops and glory goes to the marketing people. On Wall Street, quants are often abused by traders, most of whom have confused their stock portfolios in the bull market with their IQs.

My students need to see that the finance profession of the future will belong to the math-skilled. Just take a look at the composition of people in hedge funds – most have PhDs in quantitative disciplines. As it is often said – “The Geek shall inherit the Earth” !!