Living (Slightly More) Rationally – Consistent Valuation of Time

How much is your time worth? and are you valuing it consistently?

It’s something I have been thinking about a lot after reading The Art of Thinking Clearly (awesome book by the way), since it’s one of the examples of irrationality the author pointed out, and we have to make decisions like this all the time, every single day.

The author’s example goes something like this –

You buy most of your groceries from one store, but there is another store across the street that sells milk for £1 less, for the quantity you usually buy on one trip. If you buy everything at the first store except for the milk, and buy milk at the second store, it adds 5 minutes to your trip compared to just buying everything in the first store.

Would you?

If you do, you are valuing your time at less than £12 per hour. That sounds reasonable enough.

Say now you go buy a car. You are haggling with the salesman, he is standing fairly firm at £30,500. You know if you keep at it for an hour, he will probably agree to £30,000, because no salesman will lose the sale of a £30,000 car for £500, if you are insistent enough.

Would you? Would you spend 1 hour to save £500 on a £30,000 car? Most people wouldn’t.

If you wouldn’t, you are now valuing your time at more than £500 per hour.

Humans are very bad at evaluating these kind of balances, because human brains like to think about things in proportion, even when it doesn’t make any sense.

£1 is £1. £1 from a £2 carton of milk is exactly the same as £1 from a £30,000 car. By thinking in proportions, we are thinking irrationally.


I have been trying to force myself to value my time consistently in the past few months, and while I have no idea if I am worse off or better off than if I hadn’t, it certainly made making time commitment decisions easier.

I am currently valuing my time at £10. It’s a number I drew out of thin air. It’s not based on my current salary, which is £-25,500/yr thanks to Imperial College. But I’m sure whatever salary I am going to make will be within one order of magnitude from that (£1/hr to £100/hr), so it’s a good starting point.

So what kind of decisions can you make based on that knowledge?

  • Should I spend 5 minutes to save £1 on milk? £12/hour. Yes.
  • I have £10,000 sitting in a bank making negligible interest. It’s really not that much money. Should I bother spending 3 hours every year researching how to invest it and make all the arrangements, to get a roughly 8%/yr return? 8% per year is £800/year. £266/hour. Yes.
  • I currently pay £1,000 per year on car insurance and I haven’t compared offers recently. If I spend an hour looking around and making a few phone calls, I can probably save at least £100. At least £100/hour. Yes.
  • Should I spend 5 minutes filling out on online survey for a 1 in 10000 chance of winning an iPad? Expected return is 0.0001 * £500 = £0.05. £0.60/hour. No.
  • I have 5 LED bulbs consuming about 50W total. I need to go out for an hour. Is it worth spending 20 seconds to turn them off? Price of electricity in London is about 15p/kWh. Price of the bulbs are £50 combined, and have expected lifetimes of 15,000 hours. The cost of leaving them on for an hour is 0.75p (electricity) + 0.33p (aging). Value for my 20 seconds is £1.94/hour. No. Worth it if you can do it in 4 seconds or less though! 2 seconds if you are away for half an hour. Obviously never go back home if you forgot to turn off your lights, unless you’ll be gone for months.
  • Should I drive to work (30 minutes) or take public transit (1 hour)? According to some random site, cost of driving for 30 minutes a day in London is about £3,000/year. Cost of a 2 zone annual Oyster pass is £1,284. 30 minutes saved per work day * 5 working days per week * 52 weeks per year = 130 hours. Extra cost of driving is £13.2/hour. No. Probably yes if you are in the US where gas/petrol price is more reasonable, though.
  • Should I prepare fruits myself (select 5 kinds, buy, store, peel, cut, etc, £1.50), or just get an expensive £3 platter from Waitrose(*) that contains 5 servings of different fruits? It would take me about 20 minutes more to prepare fruits. £4.50/hour. Waitrose.
  • I forgot some coupons for the restaurant I am going to at home and didn’t realize until I’m on the road. It would take me 20 minutes to go back and get it, for £2 off. Should I go back and get it? £6/hour. No.
  • You bought something for £5, and find out that you don’t actually need it. Should you spend 15 minutes going to the store, 15 minutes queuing and explaining, and 15 minutes going home? £6.66/hour. No.

As you can see, many things are very clearly worth it or not. Next time you have to make a decision on whether to make a time commitment or not, try doing some rough calculations in your head, and you may be surprised how easy the decision really is, and how often your intuition is wrong!

If you make more than £20/hour or so, you’ll find that most small things are really not worth your time, while no matter how much you make, anything to do with larger amounts of money (insurance, car purchase, etc) will be worth your time, so don’t feel like you are wasting time spending hours researching on a new car! Feel like you are wasting time turning lights off instead!

We are not taking into account other rewards like happiness and environmental-feel-goodness, etc.

Also, go read the book!

* For my non-British friends, Waitrose is a relatively high end (aka expensive) supermarket chain

Miss Saigon


Now as you probably already know, I am no romantic by any stretch of imagination, even if you stretch it along the principal component. Luckily, being a romantic is not a requirement for enjoying this musical – this is quite possibly the best romance I have ever seen.

It’s the story of an American soldier falling in love with a Vietnamese bar girl (prostitute) in Saigon, during the Vietnam War. They were separated for years when Saigon fell into the hands of the communists, and this is their story.

The story is inspired by the opera Madame Butterfly, but transported to a different setting. The opera is now on my list of things to see before I die.

There are musicals with crappy story and amazing music, or amazing story and crappy music, but it’s not often that we come across one that is amazing in both. When an epic gut-wrenching story joins forces with absolutely immaculate numbers that draw the deepest emotions, we get something like Miss Saigon.

I absolutely love all those resonant and drawn-out vibratoly pieces. Ellen’s song after confronting Kim was orgasmic. I didn’t know it’s possible for a song to convey so much sorrow. Kim’s “Finale” is also no less than amazing.

This production is a revival of the original from 1989. The cast is different and the musical itself has been slightly modified at quite a few places.

Kim in this production is played by Eva Noblezada. While it was good, it was also very different from the original by Lea Salonga. Eva’s voice sounds a lot more childish and innocent. I can’t really say I like it over Lea’s, but that’s probably only because I am a huge fan of Lea.

Story-wise… (I always read the synopsis before watching musicals because I find I enjoy musicals more that way, but I know some people treat musicals like movies, so I’ll put a spoiler guard here)

Spoiler (Click to Open)

It’s VERY hard to pick a favourite song from this musical since so many of them are so good.

Though I’d say “Please” stands out, if not just for the lyrics and all the irony in the lyrics.

Interesting trivia – the melody for “Please” was actually originally intended for another number called “Too Much For One Heart”, that was eventually cut from the musical. It’s also very good.

In this production, they actually integrated some of the lyrics from “Too Much For One Heart” into “Please”. That was super cool!

“Sun and Moon”, just for the goose bumps.

You are here like a mystery.

I’m from a world that’s so different from all that you are.

How in the light of one night did we come, so far?

Outside, day starts to dawn.

Your moon still floats on high.

The birds awake,

The stars shine, too.

My hands still shake.

I reach for you.

And we meet in the sky!

You are, sunlight, and I moon,

Joined here, brightening the sky,

With the flame of love.

“How in the light of one night have we come so far?” is sung again at the very end of the musical, but has a very different meaning *melt*.

Go watch it! If you are not in London, fly here and go watch it!

Gliding – You Have to Look Up to See Clouds

abFlying an airplane is like bulldozing our way through the sky. For the most part, we don’t really care what nature is doing, as long as it’s not trying to kill us. We have an engine that takes us places, and as long as nature stays out of the way, we’ll get to where we want to go. A windless and calm sky is the dream of an airplane pilot, and nature is the enemy that we must always keep an eye on, lest it decides to backstab us when an opportunity arises. We look to the nature for aesthetics, and not much else.

Flying a glider is like getting a ride on a falling leaf in strong wind. We have some influence in where the glider is going, but we are also in a constant bargain with mother nature, and ultimately, we have to rely on the forces of nature to get to places.

“Hey Gaia! If we get over the ridge, can you take us up another thousand feet? How about under that cumulus cloud over that dry-looking field? Or that cool lenticular cloud over the mountain?”

Flying a glider requires a much better understanding of how our planet’s atmosphere works, and we always have to be mindful of what air is doing by piecing together clues like the shape, movement, and arrangement of clouds, terrain features, sun positions, and shadows.

It’s almost like playing Sherlock Holmes. There’s something wickedly satisfying about that.

This Christmas, I went on a gliding trip with the Imperial College Gliding Club. We visited the famous Midland Gliding Club at Long Mynd, on top of a hill only a few kilometres from the border between England and Wales, and spent an entire week in their clubhouse.

It’s a three and half hour drive from London.

There is a lot of sheep. Apparently they sometimes have to shoo sheep away to make room for a landing glider. They roam EVERYWHERE.

20150102_144511And snow, on our first 2 days. Snow makes great scenery, but also makes landings much more difficult. Human eyes require features for depth perception, and not having enough features in terrain complicates things.

This is the view from the clubhouse at daybreak.

20141229_082302And this is what the airfield looks like. Runway? What runway?

There’s also the yellow winch at the launch point.


20141229_142931Approaching to land.

20141229_144037Another problem of low temperature (technically the temperature-dewpoint spread) is high humidity. Humidity is dangerous because it causes condensation on the windshield, and without an engine, it’s very hard to defog.

Then there’s airframe icing. We were not flying in visible moisture, so we weren’t accumulating ice in flight, but condensation on the wings + low temperature means we can get thin layers of ice on the wings before flight. It was good exercise.

In this picture of our amazing glider, you can see the film of ice on the wing. As well as totally fogged up canopy.

20141229_094346We only got 3 hours of flying on the first day, because at 2pm, the humidity has already increased to the point that the canopy was fogging up all the time, and flying wasn’t safe anymore.

Every night, we would pack both the gliding club’s gliders and our gliders into the hanger. I did not know it’s possible to cram that many gliders into one hanger. There are even gliders hanging off the ceiling!

It may not be apparent from the picture, but none of the gliders are touching. Most of them are about 5mm from touching at a few places.


I also noticed this in the hanger. Front tyre split. Serviceable? Of course! Since when has that stopped us?!

20150102_145246We were in the clouds for one day. That wasn’t a lot of fun, and there was no flying at all, but it still looked amazing.


I’m not sure if there’s a time when this place doesn’t look amazing.

On the last day, wind was very strong (30-35 kt), and in a favourable direction, so we did some bungee launching!

Bungee launch is a historical launch method that is very rarely done nowadays since it requires many helpers and very strong wind. Long Mynd, near the Welsh border, is the only place in UK (and possibly the world?) that still does it.

Essentially, the glider gets catapulted down a hill in strong wind by 6 people pulling a bungee cord.

This is my first bungee launch flight –


As you can probably tell, I was incredibly excited.

I hadn’t even SEEN a bungee launch from the cockpit before this flight, and the instructor had so much faith in me that he put me in control. I’m happy that I didn’t end up getting both of us killed.

We counted to 12 because we couldn’t see people pulling the bungee cords, and hence had no way of knowing when they had reached maximum tension. 12 seconds seemed like a reasonable guess.

I had no idea what to expect, but the launch turned out to be much easier and gentler than I had imagined. The glider practically flew itself. It felt like we just casually slid down the hill, fell, and missed the ground.

We then flew along the ridge to get some altitude – very easy thanks to the 30 kt wind directly against the ridge.

Once we reached the end of the ridge (gaining about 500 ft), the instructor took controls, dived close to the ridge, and made a low pass over the launch site at high speed through some pretty extreme turbulence due to the strong wind and our proximity to rough terrain. Just for shiggles.

After the video, we did some more ridge running and thermaling, and did some spinning to lose height, and landed after an hour. In those conditions we could have easily flew for as long as we wanted. Pretty amazing considering the fact that we were actually below airfield height at the end of the launch.

It was my first experience with spinning, since it’s no longer part of the standard US private pilot curriculum. It was pretty fun, and I recovered correctly on first try.


It was also my first experience with thermaling, and wave riding. It’s pure magic. The first time I’ve actually seen a glider gaining altitude (and we were going at about 300 feet per minute!)

There are 2 other gliders in the same thermal (column of rising air).


I’m not sure when will the next epic gliding trip be, but I can’t wait!



University Review: Imperial College London


(Image courtesy of Wikipedia… does it actually snow in London?!)

So far on this blog I have reviewed books (1, 2, 3, 4, 5, 6, 7, 8), musicals (1, 2, 3, 4), movies (1, 2, 3, 4, 5, 6), computer games (1, 2, 3, 4, 5), 3D printers (1), and an airplane (1).

Since it’s pretty clear that my blog is going to be reviews of all things under the sun, and that I don’t want to study for my exams, I am going to try reviewing a university – Imperial College London, where I have been spending the bulk of my time in the past few months.

This post is written from the perspective of a postgrad (MSc Advanced Computing), but because our course (*1) is incredibly small at 12 people, I’m trying to make it non-course-specific.

Campus and Surrounding Area

To be honest, the campus is quite underwhelming.

The campus consists of a few tightly packed mostly-ugly buildings in a rectangular block in the middle of South Kensington, probably the most expensive part of London (London Part II – South Kensington, Imperial College London).

The surrounding consists of museums, art galleries, consulates, and embassies. They probably also contributes to the perceived ugliness of Imperial, but I guess it’s better to be in an ugly building in a beautiful area rather than in the same building in an even uglier area that makes the buildings seem beautiful in comparison.

There is obviously no student parking, but that’s not too big of an issue since London’s full time congestion and good public transit means no one drives anyways.

There is also no subsidized accommodation at all for postgrads, which is more of a problem. We either have to pay an arm and a leg to live in a leaking hole somewhere nearby (among all the diplomats and billionaires), or pay only an arm to live somewhere 40 minutes away by tube. Fortunately my degree is only 1 year. I really feel sorry for people doing their PhD here.

Coming from a campus the size of South Kensington (yay for UBC!), it definitely takes some getting used to.

It’s nice to not have to walk between buildings in the rain, and being 20 minutes from the West End (*2) by tube almost makes up for it, but it’s still nice to have a bit of space.

The lack of space also affects non-academic facilities on campus. For example, food.

There are 3 main food places on campus – JCR, h-bar (restricted to masters and up), and SCR (PhDs and staff). The food is reasonably good and reasonably priced, but selection is very limited, and they are always crowded. We always go to h-bar because JCR food is absolutely terrible. If you are going as an undergrad… be prepared for terrible food (that you have to queue for 20 minutes to get).

There are small cafeterias in a few buildings that all sell the same things (sandwiches mostly).

Academic Facilities

This section is specific to Department of Computing for the most part.

The facilities are amazing. Imperial is a very well funded university, and it really shows in their hardware investments.

We have our very own 13000 cores cluster to play with. How awesome is that?! There is also a 32 core 512 GB RAM system we have SSH access to. It may not sound very important, but they are very convenient if your work requires high computation power. It’s very nice to be able to do a parameter optimization run in a few minutes rather than overnight. Or a large scale Monte Carlo analysis. Or something.

There is also an internal Amazon EC2-type service, for people trying to host servers, etc.

We are also very rarely out of lab machines, unlike at UBC where we have to wait 20 minutes for lab machines at peak times. The lab machines are all very well equipped with minimum 4 cores, crapload of RAM, and some have GTX 780 and Quadro/FirePro for people doing graphics or GPGPU work. All lab machines run Linux, and are all accessible over SSH, and there is a distributed task system that allows us to distribute arbitrary parallel workload to be run on spare cycles in all those machines. That’s about 1000 IvyBridge and Haswell i7 and Xeon cores, across 250 quad core nodes.

There is also a hackspace in electrical engineering building with many 3D printers, a laser cutter, and a bunch of other tools. I haven’t had time to check it out, yet.

No complaints in this department.


Imperial is one of the top universities in the world, so we do get a fair share of famous professors. It’s nice to be taught by leaders in their respective fields, but the downside is that they are all incredibly busy, and don’t really have much time to talk to us.

You can tell that they are really making an effort to talk to students, but they just don’t have time for the most part.

Most of them are pretty good at teaching, though I have only taken 4 courses, so there is high sampling error.

Class sizes aren’t usually too bad, but there are a few very big ones (like the intro to machine learning course).

TAs are generally helpful and know what they are talking about.


There is a saying that if you are not the worst programmer in an office, you are in the wrong office. It’s something I always strive for – to work with people more capable than I am, and I think I’ve found just the right place for that.

This is perhaps the biggest advantage of going to a competitive university – there are no stupid people (sorry :P).

At UBC, if you are randomly put in a group of 6, chances are there will be 2 people who have no interest at all in the subject matter and are only doing the degree because they heard it pays well (or their parents told them to), 1 person really struggling with the course and requires explaining everything 5 times, 1 person who is failing anyways and doesn’t care, and 1 other useful member of the group.

At Imperial, that just doesn’t happen. Everyone is competent enough to get into this university (though even I managed to get in, so maybe the standard is not very high after all), and most importantly, passionate about the subject matter. It’s nice to work with smart people (like our machine learning group, which is pure amazingness), where when you explain ideas to each other, you never really have to say anything twice, and everyone will actually get it. We can all brainstorm at a very fast pace, and don’t need to spend the bulk of the time keeping everyone on the same page.

Imperial has the reputation that it’s full of nerdy people. While that may be true to some extent, Imperial is also known to have very active and well funded student societies.

I am part of 6 different societies, and I find that the distinguishing quality of Imperial people is dedication. Not just dedication to academic work, but also other things in life.

People in the SCUBA diving club are dedicated to diving (they are amazing – volunteer instructors to spend hours with us in the pool, when they have their studies/research to worry about as well); people in the gliding club are dedicated to gliding – the captain wakes up at 6 on both Saturday and Sunday every weekend to take people to the airfield, and spend the whole day there; people in the archery club are dedicated to archery, and go to competitions all the time, in addition to teaching all us newbies.

No one does anything half-heartedly, and it’s mutually infectious. This is probably what I love the most about Imperial.

People definitely don’t go clubbing and such as much. I don’t care. I have never and will probably never go anyways. We usually have better things to spend our time on.

Demographics-wise, Imperial has a reputation of being full of Chinese students. Well, whoever said that have obviously never been to Vancouver.

The student population is probably about 10% Chinese, and the rest is a pretty even mix of all European countries. There seem to be quite a few people from Germany and Spain, but there are some British as well, Singaporeans, and eastern European/Russian. North America is definitely under-represented. But that’s fine, I know way too many North Americans already on the other side of the pond :). It just seems like North Americans don’t generally come to Europe for university, and British people don’t generally go to North America. North Americans are so under-represented here that we actually have a North American society.

Other Asian countries also seem to be under-represented. I haven’t met anyone from Japan or Korea, and I’ve met people from probably 15+ countries already.

It’s a much more culturally-diverse mix compared to even Vancouver, and it’s awesome! All the cool stories!


Imperial does have a high reputation (at least outside of the US), and I’m not sure if it’s a blessing or a curse.

It has been ranked anywhere from 2nd in the world to 20th in the world, depending on who you ask, and curiously, some people are quite caught up on that.

Did you know that people prefer to read magazines that rank their universities higher? Is it really surprising that British magazines all rank British universities higher, and American magazines all rank American universities higher?

They provide a few different measures, and add them together using weights drawn out of thin air, tweak them so the scores of the top universities come very close, and compare universities to second decimal places. You can tweak those things to say anything you want.

There is often an air of snobbery. People feel they are somehow superior just because they go to a university some magazine editor decides is better than another. It’s pretty annoying, but I suppose it’s unavoidable at any good university.

That’s much more prevalent among undergrads (at least the ones I talked to at society meetings and events).

I still remember one of my very first engineering lectures at UBC (that’s almost 7 years ago!). I don’t remember what course it was or which professor it was, but he said something to the effect of –

Be proud of what you do, because engineers are doing something valuable for mankind and making the world a better place… but not with the arrogance of those in the medical profession.

It’s easy to become arrogant when success seems almost too easy, and I’m sure I am arrogant at times, but it’s something I’m working to fix.

We must not fall victim to that. The day we start becoming arrogant is the day we stop learning, and engineering requires life-long learning.

*1: For my North American friends – in the UK, they use the term “course” also to refer to a degree program(me)

*2: One of the 2 biggest centres of performing arts in the world, the other being Broadway in New York. Dream for musical-goers!



It was pretty good.

What does it feel like to play the lead role on a popular West End musical at the age of 8 or so? I don’t know, but it was amazing! Her acting and singing were incredible.

I looked up the girl who played Matilda (Matilda Shapland – yes, her real first name is actually Matilda), and apparently her only prior stage experience was as little Eponine in Les Miserables. That’s a pretty big jump! I don’t think little Eponine even has any lines!

The children songs in this musical have a lot of words, and some parts are almost like rap.

Another recurring feature is word play and twisty language.

The most iconic of the children’s songs is probably ‘School Song’ –

It’s catchy and fun, but I’m not quite used to it yet. I think I still prefer singing in musicals to be more operatic, as I don’t usually care as much about the lyrics as the melodies.

But that’s purely personal preference, and the musical is still very well done, and if you are a linguist type, you’ll love it!

Story-wise, I really wasn’t expecting much since it’s a children’s book, but there is actually a beautiful story behind all this madness, so I was quite pleasantly surprised!

PS. Cambridge Theatre seats are much easier on the butt.

Next week – The Book of Mormon