Showing posts from 2015

Interestingly uninteresting

This idea came about first while hiking: say you were leaving a place, and knew you'd come back in the future. You also have an object you want your future self to have, but you can't take it with you, so decide instead to leave it somewhere and pick it up on your return. Where would you leave it?

To add some constraints: (a) you're not sure exactly when you'll return. Maybe 5 years, maybe 50. Also, (b) you prefer populated areas to those with lower density (faster to pick it up when you return). In maths terms, you're trying to minimize #visits(place) / #visits(surrounding areas) - that is, the fewer times people visit where you leave it, the better (ideally 0) but it's also good if people visit the
places close by often.

I eventually settled on somewhere like under unkempt plants near an industrial zone of a stable business (unlikely to change, also near road/foot traffic going to the building), but realized that really want I wanted was a really unin…

Sounds good - part 1

I've spent a bit of time recently on one particular coding project of mine: Go-Sound, which is a library for sound manipulation and analysis written in Golang. When explaining it to people however, it turns out that not many people know how sounds work - indeed, I didn't until recently - which is interesting as it's something we use all the time (statistically, you're probably hearing something while reading this) but don't really know much about. This post is an introduction to the library, but also hopefully serves as a tutorial about what sound actually is.

Sound = changing pressure
When you hear a sound, what are you actually sensing? Sound waves are actually changes in pressure that are picked up by your eardrum. When you hit a drum, or pluck a string, or blow air through a tube, you are vibrating the air, and these pressure changes travel out in all directions - if they hit an ear, those changes will get interpreted as sounds. Once convenient way to represent …

Shortest possible ambiguity

I'm procrastinating cleaning up an essay, so instead it seemed worthwhile making a short observatory blog post - one ambiguity in English that has come up a few times for me, is often missed, but also is due to a single letter word: 'a'.
An example of the ambiguity is the following question: "When rolling a normal die (faces 1, 2, 3, 4, 5, 6), what is the probability that a number is the result?". Unless you're trying to find corner cases ("it might get stuck on an edge!" - seriously, ignore these, the point still stands), your answer will either be "1/6" or "100%", and they're both right.
The two interpretations can be thought of as: "...what is the probability that a particular single number (e.g. '5') is the result?", in which case, it's 1/6. The other is: "...what is the probability that the result will be in the set of things we classify as 'numbers'?", in which case 100%. The seco…

I predict a riot

Since starting my Cognitive Systems degree, a number of people have asked what exactly that entails. Other than the more standard stuff (psychology & computer science), I figured it worth looking into one of the things I've been contemplating that may help to summarize it: predictive ability.

1. Macro prediction

It's no surprise that it's useful for people to predict stuff: daily weather forecasts, and structural integrity of buildings come to mind, but really everything uses it in some way. Science as a whole appears to be built around this idea: your theory's utility is strongly tied to its predictive power (i.e. measurable and replicable). What's more, gaining predictive power is hugely incentivized financially: the stock market is the most obvious example, but also a large amount of machine learning is going into things like predicting behaviour of consumers, or populations, or the environment etc...

This leads to some interesting questions: is our ability g…

Side Projects

One question that often comes up at when chatting with other programmers I've met since moving to Vancouver is: "What are you working on?". The vast majority of people seem to have side projects that they work on even if employed full time, and it's a convenient conversation starter - one of the reasons I switched to being a student was having more cycles to pursue these types of projects, so it seemed worthwhile documenting what I've been up to - either just for information, or also hopefully there's some interest overlap with others looking for projects. So, ordered roughly on how useful they are:

Line Tracker (
I've always tracked my budgets (how much I'm spending, how much I have saved, and where it's stored) but the spreadsheet I was using grew out of hand when I started work (new bank accounts, super, and $US shares) and even more when I changed country, so I wanted to automate it. You create 'lines', …

Reading up on AI

In my downtime before uni, between doing some hiking and coding, I figured I'd get into the Cognitive Systems vibe by reading up a bit, and this seems to end up often at some discussion of super-intelligent AI. I'll probably be writing up a bunch of these over the period of my course, but first up: one observation made at lesswrong from a GiveWell director - in particular, distinguishing between 'agent' (active) and 'tool' (passive) AI, see objection #2. The basic idea is that it is much safer to design 'tool' AI, as it just gives you data and does take action itself, and I'd recommend reading that article first and thinking about it before returning.

I think overall it's a good way to start thinking about the problem, but my take on this can be illustrated by the following tale (giving examples through stories seems popular in this area):

* * *
Investech was a company of researchers and quants, who had a small amount of success writing computati…

Android PatFute

While reading my past blog posts due to its anniversary, I found in one of my posts from 10 years ago (mid-year 2005!) that International PatFute day is July 7th.

For some context, about 11 or 12 years ago, when first learning programming, I was teaching myself by writing a game for windows (in Visual Basic, no less). Having way more maths skills than artistic ones, it ended up being a physics simulator thinly veiled as a soccer game - the edges of the pitch are fixed solid lines, and the ball plus all the players are circles, bouncing off everything else.

Then, as you can see in my blog, I wrote it again when learning C++ and 3D graphics - this time the players were cylinders, and the ball gained height on kick, but everything else worked the same way. Little did I know, that this foreshadowed the real sport of Bubble ball many years later.

When first learning web development, I then re-wrote a javascript version using web canvas, but sadly the code for that has been lost. I later tr…

New research proves that thing you agree with!

I'm assuming readers know what Facebook is (or, social media) - if you don't, this probably won't be interesting. For those that do, you may have recognized that when you click to read a shared article, underneath will appear similar articles you may also be interested in. The idea for this post came about after doing just that, and the following was the result:
It's probably trick to read at that size, so to summarize: The original link was a Jezebel article about research published in September 2014 in Personality and Social Psychology Bulletin, where they quote the abstract: "On a daily basis, when people felt more insecure about their partner's feelings, they tended to make their relationships visible".The first suggested link was from HuffPo about research published in July 2013 in Social Psychological and Personality Science. It doesn't quote the abstract but summarizes it, including how the study "found that participants were more likely to…

Internationally taxing

I've advocated a number of times (e.g. this post) the benefit of analysing an issue by considering multiple viewpoints, and have been annoyed how so few articles do so (i.e. I don't trust anyone's analysis if they can't name a few reasons why those who disagree could/should do so...). Time to try living up to my own standards.
The topic? Something that has come up a lot in Australia at least, which is the taxation of multinational internet-economy-based corporations (MNC). Full disclaimer: I used to work at one, but was in no way involved in the financial/political side. I no longer work there, and the views contained here were mine beforehand too, and not based on any knowledge internally.
To start, a brief summary: The internet is widely used in Australia (like most of the western world) and there are a number of companies founded internationally who profit from selling products or services to people in Australia. In discussions for the recent budget, the Australian …

A long long time ago....

It came to my attention not all that long ago that, 10 years ago today, the first ever padsterprogramming blog post was made! It's really weird to think I've been recording thoughts in here for the last ten years, and all that has happened in that time (Blogger looks different, for one, as does my blog template...).

I read through all the posts last night in order to catch up with what I was doing over the last decade; apparently there was a time before I was doing TopCoder designs and ACM contests - the first post is from first year uni, so I was still into coding, but with a lot ahead of me yet...

Amusingly, there was quite a bit similar - apparently I was watching survivor (and it was already season #10: Palau. it's still going, now up to #30). I was planning on getting a 'proper watch' - which I recently just did again, upon leaving Zurich (Aerowatch this time, not Rado though). I was starting at Uni (oooh, so many posts about uni...), which will happen again i…

Raspberry cheesecake in a mug

I recently found out it's possible to make a cheesecake in ~10 minutes with only four things to clean and not much to throw out - a pretty good combination!
This is mostly a note for my future self to remember how to do this, but it might be of interest to anyone who (a) likes cheesecake, and (b) likes quick and simple cooking - which is most people, right? I had bookmarked a recipe a few years ago for microwave mug cheesecake, but I didn't have a microwave at the time (whoops...) - having moved recently I now have access to said equipment so decided to give it a go for a mother's-day dessert.

Step 0: Prepare Above is all you need, really! Full list:
1 egg white125g cream cheese (exactly half the tub above)~60ml sour cream (not sure exactly, I used ~a third of the tub, about three tablespoons)2 teaspoons of sugar5 teaspoons of raspberry pulp/jam (either pre-pulped, or mash it yourself).  1 biscuit (Butternut snap is perfect if you can get it) There's lots of room for ad…

Kindling #3

This post is from a series of review posts - for the whole list, see my Kindling page.

There's a bit of a short lull while I work out how to write the next few posts and what exactly they should be about, but I've been doing a lot of reading recently due to travel/leaving work; as I was about to clear some books off my Kindle I figured it worth reviving an earliertrend of mine and captured notes for what I made it through recently for those interested now or in the future. So, to summarize my thoughts for the novels just removed:

Dark Places (Gillian Flynn) - Having seen Gone Girl and immediately thinking it'd be awesome if it were a Palahniuk book focussed on Amy, it seemed a good idea to read another from the same author. Dark Places is Flynn's second novel (before Gone Girl) and already is being turned into a movie, which surprised me a bit as it's a lot less marketable than first movie. The characters are certainly strange enough to be from a Palahniuk novel (e…