## Conductors and CAPM

For a long time I used to wonder why orchestras have conductors. I possibly first noticed the presence of the conductor sometime in the 1990s when Zubin Mehta was in the news. And then I always wondered why this person, who didn’t play anything but stood there waving a stick, needed to exist. Couldn’t the orchestra coordinate itself like rockstars or practitioners of Indian music forms do?

And then i came across this video a year or two back.

And then the computer science training I’d gone through two decades back kicked in – the job of an orchestra conductor is to reduce an O(n^2) problem to an O(n) problem.

For a  group of musicians to make music, they need to coordinate with each other. Yes, they have the staff notation and all that, but still they need to know when to speed up or slow down, when to make what transitions, etc. They may have practiced together but the professional performance needs to be flawless. And so they need to constantly take cues from each other.

When you have $n$ musicians who need to coordinate, you have $\frac{n.(n-1)}{2}$ pairs of people who need to coordinate. When $n$ is small, this is trivial, and so you see that small ensembles or rock bands can easily coordinate. However, as $n$ gets large, $n^2$ grows well-at-a-faster-rate. And that is a problem, and a risk.

Enter the conductor. Rather than taking cues from one another, the musicians now simply need to take cues from this one person. And so there are now only $n$ pairs that need to coordinate – each musician in the band with the conductor. Or an $O(n^2)$ problem has become an $O(n)$ problem!

For whatever reason, while I was thinking about this yesterday, I got reminded of legendary finance professor R Vaidya‘s class on capital asset pricing model (CAPM), or as he put it “Sharpe single index model” (surprisingly all the links I find for this are from Indian test prep sites, so not linking).

We had just learnt portfolio theory, and how using the expected returns, variances and correlations between a set of securities we could construct an “efficient frontier” of securities that could give us the best risk-adjusted return. Seemed very mathematically elegant, except that in case you needed to construct a portfolio of $n$ stocks, you needed $n^2$ correlations. In other word, an $O(n^2)$ problem.

And then Vaidya introduced CAPM, which magically reduced the problem to an $O(n)$ problem. By suddenly introducing the concept of an index, all that mattered for each stock now was its beta – the coefficient of its returns proportional to the index returns. You didn’t need to care about how stocks reacted with each other any more – all you needed was the relationship with the index.

In a sense, if you think about it, the index in CAPM is like the conductor of an orchestra. If only all $O(n^2)$ problems could be reduced to $O(n)$ problems this elegantly!

## Spirit of Rangeela

The bad news is that Rangeela songs are not available on Spotify (my music streaming app of choice). The good news is that instead I turn to Youtube to watch them, and get the “full experience” instead.

It’s 25 years since Rangeela released, and Mint has done a feature on “25 reasons to love Rangeela“. Here are my own thoughts on why I loved the movie and why it had such a big influence on my life.

I remember the date when I watched Rangeela. 25th October 1995. It was the last day of an epic long weekend caused due to Diwali and a total solar eclipse. Two of my cousins were visiting us, and the previous day, after the eclipse had passed, we had gone to watch The Mask (along with my dad). On the 25th, we went to watch Rangeela.

I watched Rangeela in the theatre only once (sadly, in hindsight), and watched it sitting next to my dad (and cousins). I was nearly 13 years old. We had gone to Urvashi, which was then (and maybe even now) one of Bangalore’s biggest cinema halls. Urvashi had recently undergone a makeover, getting a Dolby stereo system in the process. And I had never listened to Rahman’s music before.

I remember it being a insane experience. It was so insane (in a positive way) that even today, 25 years later, listening to the songs rekindled the memory of sitting in Urvashi, and imagining Rahman’s sounds hitting my ears from all directions. And to combine that with the awesome visuals – remember that I had just hit puberty and this was one of my first movies after that event (The Mask, obviously, being another).

Watching the videos on Youtube now, I still think Urmila Matondkar looks stunning in the movie. Even otherwise, the cinematography is first grade, and the visuals are stunning. I can only imagine how the 12-year-old me might have felt looking at all that on a big screen back then (with my father sitting right next to me).

I have written here earlier about how the teens are possibly the optimal years of movie appreciation.  And it was influential for sure. For the next couple of years, Spirit of Rangeela was a fixture for choreography shows at inter-school cul-fests. Some of us little teenagers who assumed we were jilted in love sang (or whistled) Kya Kahe Kya Na KaheTanha Tanha, of course, was yet another level.

Sometimes I wonder, if the movie would have had the same effect on me had I not watched it on a really large screen, in a theatre with awesome audio. Maybe Rahman’s Hindi debut deserved that.

My apologies if this post appears scattered. I’ve been listening to (and watching) the songs of Rangeela on loop for the last two hours, and it has triggered all sorts of thoughts in me. And there have been too many things to write here.

Maybe I should’ve done a tweetstorm instead.

## Wheels of the bus went swimming one day

One story I like to tell is about how Mozart charged so much for setting Twinkle Twinkle to tune (if he did set it to tune, that is) that propagators of nursery rhymes decided to use the same tune for several other popular songs – most prominently for ABCDEFG and with a small variation for Ba Ba Black Sheep. It’s confusing, not just for kids but also for the parents. I’d written here a month or so back about how I would play tunes on the keyboard and Berry would try to guess the song and sing along. As someone who sets quizzes occasionally, the lack of “a unique answer” drives me nuts. And it possibly drives Berry nuts as well, since she changes from twinkle twinkle to ABCD within the course of one stanza. I wonder why this is the case. Using my one data point (Berry) kids can catch on to tunes pretty quickly (she was barely a year old when she started humming the tune of Black Sabbath’s Iron Man. Now she knows the full lyrics). And having unique tunes for songs means that kids are able to make easy associations between music and words – always a desirable thing. And the lack of one-to-one correspondence doesn’t just run one way – sometimes there are multiple ways in which the same song can be sung. For some songs, such as Happy Birthday, this is due to copyright issues. I’m not sure why other songs are sung in different tunes. For example, there are two clearly different ways in which the third line of itsy-bitsy/incy-wincy (depending on which side of the pond you’re on) spider is sung, and it gets especially confusing when I’m playing on the keyboard, since I don’t know which version Berry is expecting ( we invariably sing/play the “other” way). The usage of voice controlled players has made things worse. In fact, the first time I appreciated Siri on my phone was when Berry was just born, and I needed both hands to hold her and put her to sleep, and then someone turn on a lullaby (“Hey Siri, play iron man by rockabye baby”). Now, the problem with voice-controlled playing is that when there are multiple versions of the same song you don’t know which one will get played. An extreme case is like earlier today we asked Alexa to use Amazon Unlimited (we have a 3-month free trial, possibly because of my Prime membership) to play “london bridge”. It belted out some dhinchak EDM song! Within the realms of nursery rhymes itself there are songs that are sung to completely new tunes (like I had never expected that there exists a version of Jack and Jill sung to the tune of Yankee Doodle. It is most annoying). It is extremely disorienting for me – and I guess it is for kids as well, for I’m told they like predictability. I don’t know what can be done to restore the sanity of one-song-one-tune.  Yes, I can record a set of songs in unique and popular tunes, but there is no guarantee that it will take off. And with the increase of voice controlled music playing, there is no guarantee that the “bad tunes” won’t get any air time. The title, for those that didn’t get it, is a portmanteau of two songs that share a name. I must mention I have no intention of popularising these two precise renditions of these songs – they were simply on top of the search engine results.
Mommy duck said quack quack quack, all day long! PS: There are differing versions in lyrics as well. One version says “all day long”; another says “all the way to town”. As Aditya Narayan sang in Rangeela Re 23 years ago, it’s complicated being a kid.

## Selection bias and recommendation systems

Yesterday I was watching a video on youtube, and at the end of it it recommended another (the “top recommendation” at that point in time). This video floored me – it was a superb rendition of Endaro Mahaanubhaavulu by Mandolin U Shrinivas. Listen and enjoy as you read the rest of the post.

I was immediately bowled over by youtube’s recommendation system. I had searched for both Shrinivas and Endaro … in the not-so-distant past so Youtube had put two and two together and served me up an awesome rendition! I was so happy that I went to town twitter about it.

It was then that I realised that this was the firs time ever that I had noticed the top recommendation of Youtube. In other words, every time I use youtube, it recommends a video to me, but I seldom notice it. And I seldom notice it for a reason – they’re usually irrelevant and crap. The one time I like the video it throws up, though, I feel really happy and go gaga over the algorithm!

In other words, there’s a bias which I don’t know what its exactly called – the bias that when event happens in a certain direction, you tend to notice it and give credit where you think it’s due. And when it doesn’t happen that way, you simply ignore it!

In terms of larger implications, this is similar to how legends such as “lucky shirts” are born. When something spectacular happens, you notice everything that is associated with that spectacular event and give credit where you think it’s due (lucky shirt, lucky pen, etc.). But when things don’t go your way you think it’s despite the lucky shirt, not because the shirt has become unlucky.

It’s the same thing with belief in “god”. When you pray and something good happens to you after that, you believe that your prayers have been answered. However, when you pray and something good doesn’t happen, you ignore the fact that you prayed.

Coming back to recommendation systems such as Youtube’s, the problem is that it is impossible for a recommendation system to get recommendations right all the time. There will be times when you get it wrong. In fact, going by my personal experience with Youtube, Amazon, etc. most of the time you will get your recommendation wrong.

The key to building a recommendation system, thus, is to build it such that you maximise the chances of getting it right. Going one step further I can say that you should maximise the chances of getting it spectacularly right, in which case the customer will notice and give you credit for understanding her. Getting it “partly right” most of the time is not enough to catch the customer’s attention.

Putting marketing jargon on it, what you should focus on is delighting the customer some of the time rather than keeping her merely happy most of the time!

## On Walking out of a play

Last night the wife and I went to watch what we thought was going to be a play at KH Kala Soudha in Hanumanthanagar. It was supposed to be “directed” by RJ Vinayak Joshi and “starring” among others TN Seetharam, Master Hiriyannaiah and others. It turned out to be more like a talk show, where Joshi attempted to ‘interview’ these worthies, and they came up on stage and sat on a bench and put senti. And talked on, and on, and on.

I’m not saying it was a total ripoff. The band that was playing at the side was pretty good, with the singers having quite distinctive voices and the music also being quite nice. There was this little standup piece by this guy called Nagaraj Kote, which was probably the only part of the evening that lived up to the announced title ‘Simple is difficult’. Then, there was this frequent dialogue between Joshi, playing “naanalla” (not me) and this other guy playing “gottilla” (i don’t know). And they invited this really old couple to talk about their 50-year-old marriage, and they turned out to be quite funny!

Actually, despite some 15-20 mins of senti by Seetharam sometime in the middle, everything seemed to be going quite well. It was 9 o’clock and time for the “play” to be over. And then Master Hiriyannaiah came up on stage. And started talking. And talking. And talking. He was supposed to be taking a dig at politicians, and he ended up talking just like one of them. Rambling on and on and on. And on and on and on. The band had by then gone off stage, else they could’ve played LedZep’s Ramble On and salvaged the evening.

So there was this debate between the wife and I about whether it was ethical to walk out. A few minutes after Hiriyannaiah started rambling, I thought the theatrepeople had broken their part of the contract – as long as they were within the time that they advertised, they were good. And we were obliged to hold up our end of the contract. But once they overshot, I felt no need to hold up my end of the contract, and having given them the gate money, and my promised 90 minutes, I was now free to walk out.

Of course, I wasn’t going to do something outrageous – like shouting or screaming or talking on my mobile or anything else that might cause disrespect to the performers. All I wanted to do was to walk out.

The wife, on the other hand, felt it would be insensitive on our part to walk out, and that it too would amount to disrespect, and we ought to stay till the end of the show. Her thinking reminded me of what happens in an interest rate swap when one party goes bankrupt – the counterparty is obliged to continue paying it’s share of the swap, and hold up its end of the contract.

I think there’s merit in both sides of the argument, and I kept debating that as I waited until the end of Hiriyannaiah’s rambles when I really couldn’t take it any more and I walked out. So what do you think of this? Do you think it’s ok for performers to expect perfect behaviour from the audience even after they’ve not held up their end of the contract? Do you think it’s ethical for people to quietly walk out of a play that they’re not enjoying at all, as a means of protest? Don’t you think it helps having this part of the feedback loop?

## Fighterization of food

One of the topics that I’d introduced on my blog not so long ago was “fighterization“. The funda was basically about how professions that are inherently stud are “fighterzied” so that a larger number of people can participate in it, and a larger number of people can be served. In the original post, I had written about how strategy consulting has completely changed based on fighterization.

After that, I pointed out about how processes are set – my hypothesis being that the “process” is something that some stud would have followed, and which some people liked because of which it became a process. And more recently, I wrote about the fighterization of Carnatic music, which is an exception to the general rule. Classical music has not been fighterized so as to enable more people to participate, or to serve a larger market. It has naturally evolved this way.

And even more recently, I had talked about how “stud instructions” (which are looser, and more ‘principles based’) are inherently different from “fighter instructions” (which are basically a set of rules). Ravi, in a comment on Mohit‘s google reader shared items, said it’s like rule-based versus principles-based regulation.

Today I was reading this Vir Sanghvi piece on Lucknowi cuisine, which among other things talks about the fact that it is pulao that is made in Lucknow, and now biryani; and about the general declining standards at the Taj Lucknow. However, the part that caught my eye, which has resulted in this post with an ultra-long introduction was this statement:

The secret of good Lucknowi cooking, he said, is not the recipe. It is the hand. A chef has to know when to add what and depending on the water, the quality of the meat etc, it’s never exactly the same process. A great chef will have the confidence to improvise and to extract the maximum flavour from the ingredients.

This basically states that high-end cooking is basically a stud process. That the top chefs are studs, and can adapt their cooking and methods and styles to the ingredients and the atmosphere in order to churn out the best possible product.You might notice that most good cooks are this way. There is some bit of randomness or flexibility in the process that allows them to give out a superior product. And a possible reason why they may not be willing to give out their recipes even if they are not worried about their copyright is that the process of cooking is a stud process, and is hence not easily explained.

Publishing recipes is the attempt at fighterization of cooking. Each step is laid down in stone. Each ingredient needs to be exactly measured (apart from salt which is usually “to taste”). Each part of the process needs to be followed properly in the correct order. And if you do everything perfectly,  you will get the perfect standardized product.

Confession time. I’ve been in Gurgaon for 8 months and have yet to go to Old Delhi to eat (maybe I should make amends this saturday. if you want to join me, or in fact lead me, leave a comment). The only choley-bhature that I’ve had has been at Haldiram’s. And however well they attempt to make it, all they can churn out is the standardized “perfect” product. The “magic” that is supposed to be there in the food of Old Delhi is nowhere to be seen.

Taking an example close to home, my mother’s cooking can be broadly classified into two. One is the stuff that she has learnt from watching her mother and sisters cook. And she is great at making all of these – Bisibelebhath and masala dosa being her trademark dishes (most guests usually ask her to make one of these whenever we invite them home for a meal). She has learnt to make these things by watching. By trying and erring. And putting her personal touch to it. And she makes them really well.

On the other hand, there are these things that she makes by looking at recipes published in Women’s Era. Usually she messes them up. When she doesn’t, it’s standardized fare. She has learnt to cook them by a fighter process. Though I must mention that the closer the “special dish” is to traditional Kannadiga cooking (which she specializes in), the better it turns out.

Another example close to home. My own cooking. Certain things I’ve learnt to make by watching my mother cook. Certain other things I’ve learnt from this cookbook that my parents wrote for me before I went to England four years ago. And the quality of the stuff that I make, the taste in either case, etc. is markedly different.

So much about food. Coming to work, my day job involves fighterization too. Stock trading is supposed to be a stud process. And by trying to implement algorithmic trading, my company is trying to fighterize it. The company is not willing to take any half-measures in fighterization, so it is recruiting the ultimate fighter of ’em all – the computer – and teaching it to trade.

Preliminary reading on studs and fighters theory:

Studs and Fighters

Extending the studs and fighters theory

## Lazy post: Search Phrases: March 2009

I think I’ll make this a monthly feature: collecting the whackiest search terms that people use to land up on my blog, and posting them here. I had published one such list for February. Here goes the list for March:

• describe my job
• apprentics for carpenter in gurgaon
• can north indians survive in the south
• carnatic music pakistan
• dry fish market in orisa & madrass contact numbers
• examples of bastardization in a sentence
• how can death be postponed by chanting mantras?
• kodhi is a cheap guy
• savitabhabhi.com competition
• verb phrases of the behavior of atticus
• what are some other versions of dashavatar -film -songs -jobs -dvd -movie

## Year Ending Post

Last december 31, I wrote a this day that year post. Two years back, I had published a short story. The year before, I had written about the events of the day, and one year prior I was mugging for what was going to be a disastrous marketing exam. As I am writing this, I’m playing scrabble on facebook, and bridge with my computer. I’m listening to music, and am planning to hit the sack soon.

This afternoon I received a mail from my boss, which he said is a standard format mail he sends to friends and colleagues. It was full of pictures of him and his wife and his kids, and stories about what they did this year. About the changes and special events in each of their lives. About how the year has been from different perspectives. And so forth. I think I have received a couple of other similar mails (from US based people – this might be some american funda; my boss also lived in America till early this year) from other acquaintances (though, without pics) which I haven’t bothered to read. Since I’m clueless about what to write, I think I’ll just do a standard year-end roundup.

The most significant thing for me was my move to Gurgaon, and to this new job. That had been preceded by four months of joblessness, and more than two years of acute NED (in fact, I think it was during this period of extended NED that I actually invented the term NED).

The concept of NED also seemed to advance by leaps and bounds this year. I have heard of people who are at least three degrees away from me use it. The message of this concept seems to be spreading. I am sure that one day it will be famous, but then I’m not sure if I, as its inventor/discoverer, will get due credit.

Another significant event of the year has been the movement of this blog from livejournal to its present location. I must mention that this website has been like “glad bangles” for me. A week after I inaugurated this, I had a nice job offer, ending over a year of NED. There were a few other changes also in my life around that time, which I don’t remember now. What I do remember was classifying this website as “glad bangles”. and I like this better than Mad Angles.

On the louvvu front, it was a very quiet year, apart from one quick episode. Maybe one of the least productive years – comparable, maybe, to my years back in IIT.

Ok I think NED is happening. i just resigned my scrabble game. I had resigned my bridge game ages back, and I’d closed the program. I’m feeling sleepy now. So I’ll close it here. Happy new year. And I think this is the worst year-ending post that I’ve written in a long time. This website maybe deserved a much better new year post in the year end but it’s ok.

## Disco Raaga – Taana – Pallavi

This is one of those posts that I’ve been intending to post for over a couple of months, but each time I think about this, I don’t happen to be in front of a computer, and even if I do, I don’t feel like writing about it. So here I am – finally blogging this. As I write this, I’m listening to the Ledzep Live Album The Song Remains the Same. This post is about this album, and other related stuff.

As you might have figured out from the title of this post, one thing I’ve noticed about this album is about the approximate Carnatic format that the songs in this take on. It may not be in the strict order that Carnatic music prescribes, but these songs are roughly there. I’m currently listening to Dazed and Confused, and after the first few lines of the Pallavi were sung, Page has now gone off into an extended Aalapana of whichever Raaga this song is set in.

Periodically, they return to the song, and play a few more lines. Now, Plant is doing his bit by improvising with a few lines of his own. Jones and Bonham are dutifully doing their background stuff – Bonham will get his footage later in the album – for Moby Dick features a full-blown Tani Avartanam. It ends the same way Tani Avartanams in Carnatic concerts do – with the main line of the Pallavi being sung at the end of it. I know I might be force-fitting some Carnatic concepts into this album; nevertheless, all these improvements make for extremely interesting listening.

A few days after I had first noticed this, Udupa told me that a large number of concerts in the 70s were like this – the musicians would simply jam on stage in the middle of the songs. Created music on the spot. Spontaneous stuff. Unfortunately, Udupa continued, the trend changed a few years back when less informed audiences started demanding that more songs be crammed into the three hour concert, thus reducing the scope for such improvisations.

The best thing about Carnatic concerts is that each one is unique. You might look at two concerts – played by the same set of musicians and with the same line-up of krithis, but there is a very good chance that the two are markedly different. This is because Indian Classical music, in its concerts, encourages the musician to innovate, to play whatever comes to his mind at that point of time – while adhering to the fairly strict rules. It is this element of innovation that makes each concert special, and an experience in itself.

Western Classical music differs in this regard – especially in the orchestra form – since the large size of the troupe leaves little scope for innovation and the musicians are literally forced to play it by the book. In that context, it seems like it was genres such as rock which brought in the spontaneity and innovation into western music.

Nowadays, bands don’t tour as much as they used to a couple of decades ago, which means that whenever they visit a city (which is once in a few years), the fans in the city will want to hear as many songs as possible. And that kills innovation. It is not the bands’ fault – they are simply responding to the market. And I don’t know what it could be that could get them back to their RTP days.

Here is one of my retirement plans. For each song that I like, describe a Carnatic Raaga into which it can approximately fit into. Tinker around with the stanzas, to create a Pallavi-Anupallavi-Charana format. Try to make the raagas as rigid as possible – Vakra scales will be preferred. And then put RTP. Use some Western instruments too – for example, I definitely want the Bass guitar to be a regular feature in Carnatic concerts. I think the result is likely to be phenomenal.

It’s been a few years since I picked up the violin. I plan to do it sometime. And implement what I’ve described here. Hopefully I’ll do a good job. In the meantime, if there are any bands out there which want to implement this concept, they can feel free and do it – I promise I won’t sue them later for IPR.