Vacation Shopping

This is yet another of those questions whose answer seems rather obvious to everyone, and to me in full hindsight, but which has taken me a long time to appreciate

For a long time I never understood why people shop during vacations, when both time and luggage space are precious commodities. With global trade, I reasoned that most clothes should be available at reasonably comparable prices worldwide, and barring some special needs (such as a certain kind of shoes, for example), there was no real need to shop on vacations.

The last day of our trip to Munich in June convinced me otherwise. That was the only day on the trip that the wife was free from work, and we could go out together before our afternoon flight. The only place we ended up going out to turned out to be a clothing store, where the wife freaked out shopping.

It didn’t make sense to me – she was shopping at a chain store which I was pretty certain that I had seen in London as well. So why did she shop while travelling? And she shopped far more than she does in a normal shopping trip in London.

In hindsight, the answer is rather simple – diversity. While the same stores might exist in various countries or cities, each is adapted to local tastes and prevailing fashions. And while everyone watches the same “runways” in Milan and Los Angeles, there is always a subtle difference in prevailing styles in different places. And clothes in the stores in the respective places are tailored (no pun intended) to these styles.

And it can happen that the local prevailing styles are not something that you particularly agree with. For example, for years together in Bangalore I struggled to find plain “non-faded” jeans – most people there seemed to demand faced or torn jeans, and stores responded to serve that demand (interestingly, jeans shopping in my last Bangalore trip was brilliantly simple, so I guess things have changed).

Similarly, the wife finds it hard to appreciate most dresses in the shops in London (and I appreciate why she doesn’t appreciate them – most of the dresses are a bit weird to put it mildly), and as a result hasn’t been able to shop as much in recent times. She had taken to claim that “they don’t seem to be making normal clothes any more”.

But the styles in London aren’t correlated with the styles in Munich (or elsewhere), with the result that in that one chain store in Munich, she found more nice dresses than she had in some 20 shopping trips over a year in London.

Fashion suffers from the “tyranny of the majority“. It makes eminent sense for retailers to only stock those styles and models that have a reasonably high demand (or be compensated for stocking low-demand items with a high enough margin – I have a chapter on this in my book). So if your styles don’t match with those of people around you, you are out of luck.  But when you travel, you have the chance to align yourself to another majority. And if that alignment happens, you’re in luck!

PS: On a separate note, I’m quite disappointed with the quality of clothes in London. Across brands, they seem to wear much faster than those bought in continental Europe or even in India.

The utility of utility functions

That is the title of a webinar I delivered this morning on behalf of Kristal.AI, a company that I’ve been working with for a while now. I spoke about utility functions, and how they can be used in portfolio optimisation.

This is related to the work that I’ve been doing for Kristal, and lies at the boundaries between quantitative finance and behavioural finance, and in fact I spoke about utility functions (combined with Monte Carlo methods) as being a great method to unify quantitative and behavioural finance.

Interactive Brokers (who organised the webinar) recorded the thing, and you can find the recording here. 

I think the webinar went well, though I’m not very sure since there was no feedback. This was by design – the webinar was a speaker-only broadcast, and audience weren’t allowed to participate except in terms of questions that were directly sent to me.

In the first place, webinars are hard to do since it feels like talking to an empty room – there is no feedback, not even nods or smiles, and you don’t know if people are listening. In most “normal” webinars, the audience can interject by raising their hands, and you can try make it interactive. The format used here didn’t permit such interaction which made it seem like I was talking into thin air.

Also, the Mac app of the webinar tool used didn’t seem particularly well optimised. I couldn’t share a particular screen from my laptop (like I couldn’t say “share only my PDF, nothing else” which is normal in most online chat tools), and there are times where I’ve inadvertently exposed my desktop to the full audience (you can see it on the recording).

Anyways, I think I’ve spoken about something remotely interesting, so give it a listen. My “main speech” only takes around 20-25 minutes. And if you want to know more about utility functions and behavioural economics, i recommend this piece by John Cochrane to you.

Why AI will always be biased

Out on Marginal Revolution, Alex Tabarrok has an excellent post on why “sexism and racism will never diminish“, even when people on the whole become less sexist and racist. The basic idea is that there is always a frontier – even when we all become less sexist or racist, there will be people who will  be more sexist or racist than the others and they will get called out as extremists.

To quote a paper that Tabarrok has quoted (I would’ve used a double block-quote for this if WordPress allowed it):

…When blue dots became rare, purple dots began to look blue; when threatening faces became rare, neutral faces began to appear threatening; and when unethical research proposals became rare, ambiguous research proposals began to seem unethical. This happened even when the change in the prevalence of instances was abrupt, even when participants were explicitly told that the prevalence of instances would change, and even when participants were instructed and paid to ignore these changes.

Elsewhere, Kaiser Fung has a nice post on some of his learnings from a recent conference on Artificial Intelligence that he attended. The entire post is good, and I’ll probably comment on it in detail in my next newsletter, but there is one part that reminded me of Tabarrok’s post – on bias in AI.

Quoting Fung (no, this is not a two-level quote. it’s from his blog post):

Another moment of the day is when one speaker turned to the conference organizer and said “It’s become obvious that we need to have a bias seminar. Have a single day focused on talking about bias in AI.” That was his reaction to yet another question from the audience about “how to eliminate bias from AI”.

As a statistician, I was curious to hear of the earnest belief that bias can be eliminated from AI. Food for thought: let’s say an algorithm is found to use race as a predictor and therefore it is racially biased. On discovering this bias, you remove the race data from the equation. But if you look at the differential impact on racial groups, it will still exhibit bias. That’s because most useful variables – like income, education, occupation, religion, what you do, who you know – are correlated with race.

This is exactly like what Tabarrok mentioned about humans being extremist in whatever way. You take out the most obvious biases, and the next level of biases will stand out. And so on ad infinatum.

Relative pricing revisited

Yesterday I bought a pair of jeans. Normally it wouldn’t be a spectacular event (though one of my first blogposts was about a pair of jeans), but regular squatting has meant that I’ve been tearing through jeans well-at-a-faster-rate, and also that it’s been hard to find jeans that fit me well.

Basically, I have a well-above-average thigh and a well-below-average arse for my waist size, and that makes it hard to find readymade pants that fit well. As a consequence I’ve hardly bought trousers in the last 2-3 years, though I’ve been losing many pairs to the tear in this period of time.

And so when I found a pair of jeans that fit me comfortably yesterday I wasn’t too concerned about paying a record price for it (about 1.8 times the maximum I’d ever paid for a pair in the past). In fact, I’d seen another pair that fit well a few minutes earlier (and it was a much fancier brand), but it was well above budget (3 times as expensive as my historically costliest ever pair), and so I moved on (more importantly, it came with a button fly, and I’d find that rather inconvenient).

Jeans having been bought, we went off to a restaurant at the mall for lunch, at the end of which the wife pointed out that the money we paid for the lunch was more than the difference in prices between the two pairs of jeans. And that if only we would avoid eating out when it’s avoidable, we could spend on getting ourselves much more fancier clothes without feeling guilty.

I’ve written about relative prices in the past, especially about the Big Mac Index, and how it doesn’t make sense because of differential liquidity. After moving to London, I’m yet to come to terms with the fact that relative prices of goods here is vastly different from that back home; and that I haven’t adjusted my lifestyle accordingly leading to inefficient spending and a possible strain on lifestyle.

Food, for example, is much more expensive here than in India (we’ll use official exchange rates for the purpose of this post). The average coffee costs £2.5 (INR 225), which is about 10 times the price of an average coffee in Bangalore (I’m talking about a good quick cup of coffee here, so ignoring the chains which are basically table rentals). The average weekday takeaway lunch costs £6 (INR 540), which is again 10X what it costs in Bangalore.

Semi-fancy meals (a leisurely meal at a sit down restaurant with a drink, perhaps) are relatively less costly here, costing about £25-30 per head compared to INR 1200-1500 in Bangalore, a ratio of about 2X. A beer at a pub costs about the same, though cocktails here are much more expensive.

The alternative to eating out is, of course, eating in, and most “regular” ingredients such as vegetables and rice cost more here, though cheeses (which are relatively less liquid in India) are actually cheaper here. Milk costs about the same.

Controlling for quality, clothes cost about the same (or might even be less costly here when you go for slightly more fancy stuff). Electronics again cost about the same (they come through the same global supply chain). Contact lenses are more expensive here (though the ones I buy in India are manufactured in the UK!).

In my book, I have a chapter called “if you want to live like a Roman, live in Rome”. It’s about how different cities have different relative liquidity of goods. Similarly, different cities and countries have different relative prices, and long-term residents of these places evolve their spending to optimise for their given set of relative prices.

And when you move cities or countries, if you don’t change your lifestyle accordingly you might end up spending suboptimally, and get less welfare from life.

Once again this points out problems with international price indices being constructed based on a particular commodity, or set of commodities. For not only are different commodities differentially liquid (as I pointed out in my Mint piece linked above) in different places, but also the “standard consumption basket” also varies from city to city!

And if a Delhi-ite consumes lots of apples, and a Bangalorean consumes lots of oranges, you can’t make an apples-to-apples comparison in cost of living in these cities!

Profit and politics

Earlier today I came across this article about data scientists on LinkedIn that I agreed with so much that I started wondering if it was simply a case of confirmation bias.

A few sentences (possibly taken out of context) from there that I agree with:

  • Many large companies have fallen into the trap that you need a PhD to do data science, you don’t.
  • There are some smart people who know a lot about a very narrow field, but data science is a very broad discipline. When these PhD’s are put in charge, they quickly find they are out of their league.
  • Often companies put a strong technical person in charge when they really need a strong business person in charge.
  •  I always found the academic world more political than the corporate world and when your drive is profits and customer satisfaction, that academic mindset is more of a liability than an asset.

Back to the topic, which is the last of these sentences. This is something I’ve intended to write for 5-6 years now, since the time I started off as an independent management consultant.

During the early days I took on assignments from both for-profit and not-for-profit organisations, and soon it was very clear that I enjoyed working with for-profit organisations a lot more. It wasn’t about money – I was fairly careful in my negotiations to never underprice myself. It was more to do with processes, and interactions.

The thing in for-profit companies is that objectives are clear. While not everyone in the company has an incentive to increase the bottom-line, it is not hard to understand what they want based on what they do.

For example, in most cases a sales manager optimises for maximum sales. Financial controllers want to keep a check on costs. And so on. So as part of a consulting assignment, it’s rather easy to know who wants what, and how you should pitch your solution to different people in order to get buy-in.

With a not-for-profit it’s not that clear. While each person may have their own metrics and objectives, because the company is not for profit, these objectives and metrics need not be everything they’re optimising for.

Moreover, in the not for profit world, the lack of money or profit as an objective means you cannot differentiate yourself with efficiency or quantity. Take the example of an organisation which, for whatever reason, gets to advice a ministry on a particular subject, and does so without a fee or only for a nominal fee.

How can a competitor who possibly has a better solution to the same problem “displace” the original organisation? In the business world, this can be done by showing superior metrics and efficiency and offering to do the job at a lower cost and stuff like that. In the not-for-profit setup, you can’t differentiate on things like cost or efficiency, so the only thing you can do is to somehow provide your services in parallel and hope that the client gets it.

And then there is access. If you’re a not-for-profit consultant who has a juicy project, it is in your interest to become a gatekeeper and prevent other potential consultants from getting the same kind of access you have – for you never know if someone else who might get access through you might end up elbowing you out.

Freelancing and transaction costs

In the six years of running my own consulting business, I’d forgotten about an essential part that you need to endure as part of a job – piecemeal work. It is fairly often when you’re working for someone else that you get work that is so tiny or insignificant that you can hardly take ownership of it. The best strategy for dealing with it is to quietly get it over with and hope you won’t get such stuff again.

However, sometimes you can get caught in a rut of continuously getting this kind of work, and start wondering what you actually signed up for. And this is one thing I hadn’t expected to encounter when I got back to full time working earlier this year.

Thinking about why I never had to encounter such stuff during my consulting life, I realised there’s a fairly simple explanation – transaction costs.

Being a consultant is high transaction cost business. Every time you need to take on a new piece of work, you need to go through the charade of negotiating specifics with the client, pricing and drawing up a contract. All put together, the effort is not insignificant.

Moreover, in the line of work that I used to do, there was this massive overhead cost of understanding, cleaning and getting comfortable with the client’s data  – the effort involved in that meant that after a particular point in time I stopped taking work that wasn’t chunky enough. For a while I started refusing such work, but then got smarter and started pricing myself out of such work (though some clients were generous enough to meet that price to get their little tasks done – effectively I’d passed on the transaction costs to them).

The downside of this, of course, was that there was a fair amount of money I could have made taking up small works which I didn’t since the transaction cost was too high – this can be thought of as potential lost revenues. The upside was that whatever work I did was of high quality and (hopefully) made a big impact on the client’s business.

In the nature of the firm, Ronald Coase wrote that the purpose of the corporation was that transaction cost of dealing with co-workers can be eliminated. But then, I realise that sometimes this transaction cost can also be a good thing!

Oh, and obligatory plug here – my book Between the buyer and the seller deals with transaction costs, among other things. It’s available for sale (both in print and digital) on Amazon.


Thaler and Uber and surge pricing

I’m writing about Uber after a really long time on this blog. Basically I’d gotten tired of writing about the company and its ideas, and once I wrote a chapter about dynamic pricing in cabs in my book, there was simply nothing more to say.

Now, the Nobel Prize to Richard Thaler and his comments sometime back about Uber’s surge pricing has given me reason to revisit this topic, though I’ll keep it short.

Basically Thaler makes the point that when businesses are greedy and seen to be gouging customers in times of high demand, they might lose future demand from the same customers. In his 2015 book Misbehaving (which I borrowed from the local library a few months ago but never got down to reading), he talks specifically about Uber, and about how price gouging isn’t a great idea.

This has been reported across both mainstream and social media over the last couple of days as if Thaler is completely against the concept of surge pricing itself. For example, in this piece about Thaler, Pramit Bhattacharya of Mint introduces the concept of surge pricing and says:

Thaler was an early critic of this model. In his 2015 book Misbehaving: The Making of Behavioral Economics, Thaler argues that temporary spikes in demand, “from blizzards to rock star deaths, are an especially bad time for any business to appear greedy”. He argues that to build long-term relationships with customers, firms must be seen as “fair” and not just efficient, and that this often involves giving up on short-term profits even if customers may be willing to pay more at that point to avail themselves of its product or service.

At first sight, it is puzzling that an economist would be against the principle of dynamic pricing, since it helps the marketplace allocate resources more effectively and more importantly, use price as an information mechanism to massively improve liquidity in the system. But Thaler’s views on the topic are more nuanced. To continue to quote from Pramit’s piece:

“I love Uber as a service,” writes Thaler. “But if I were their consultant, or a shareholder, I would suggest that they simply cap surges to something like a multiple of three times the usual fare. You might wonder where the number three came from. That is my vague impression of the range of prices that one normally sees for products such as hotel rooms and plane tickets that have prices dependent on supply and demand. Furthermore, these services sell out at the most popular times, meaning that the owners are intentionally setting the prices too low during the peak season.

Thaler is NOT suggesting that Uber not use dynamic pricing – the information and liquidity effects of that are too massive to compensate for occasionally pissing off passengers. What he suggests, however, is that the surge be CAPPED, perhaps at a multiple of three.

There is a point after which dynamic pricing ceases to serve any value in terms of information and liquidity, and its sole purpose is to ensure efficient allocation of resources at that particular instant in time. At such levels, though, the cost of pissing off customers is also rather high. And Thaler suggests that 3 is the multiple at which the benefits of allocation start getting weighed down by the costs of pissing off passengers.

This is exactly what I’ve been proposing in terms of cab regulation for a couple of years now, though I don’t think I’ve put it down in writing anywhere. That rather than banning these services from not using dynamic pricing at all, a second best solution for a regulator who wants to prevent “price gouging” is to have a fare cap, and to set the cap high enough that there is enough room for the marketplaces to manoeuvre and use price as a mechanism to exchange information and boost liquidity.

Also, the price cap should be set in a way that marketplaces have flexibility in how they will arrive at the final price as long as it is within the cap – regulators might say that the total fare may not exceed a certain multiple of the distance and time or whatever, but they should not dictate how the marketplace precisely arrives at the price – since calculation of transaction cost in taxi pricing has historically been a hard problem and one of the main ways in which marketplaces such as Uber bring efficiency is in solving this problem in an innovative manner using technology.

For more on this topic, listen to my podcast with Amit Varma about how taxi marketplaces such as Uber use surge pricing to improve liquidity.

For even more on the topic, read my book Between the buyer and the seller which has a long chapter dedicated to the topic,