- American Accent Training – it’s an audio book. Lots of great advice.
- Accent’s Way on YouTube. She’s an Israeli who taught herself the American accent to a complete perfection. You wouldn’t tell. Lots of information and motivation!
In college in NZ I wrote a simple compiler for the 6802 with some friends, it fit in 2k (just) .... we called ourselves "uSoft" (with a greek mu - but we were cross-compiling from cards, no room for a mu) .... the next year we heard of some jokers in the US who were using our name, and pffft! they only had a basic interpreter, so lame!
Needless to say the jokers in the US became multi-billionaires, we were stuck on the other side of the world with no one to sell to, and no real knowledge of the marketing we'd need to bring our code to market - if only we'd incorporated we could at least have sold the name :-)
The internet has made it more clear that being an early startup employee will be worse in almost all possible cases compared to working at google even when you get to the $1 billion 'unicorn' status.
For example, I was a jr. engineer at a stage A $5 million startup with ~%0.4 of the company in stock options. When it reached its $1 billion valuation 4 years later, my options with dilution were worth x25. But $500k/4 years is $125k/yr, which is pretty close to the stock compensation working at google. But these options were not cash equivalent like google's stock, and I had to drop it all on the floor because of the 90 day window. I lost $500k in compensation because I decided to work at the startup vs. google.
Imagine if your employees had a good amount of savings and could easily afford the $10-20k it costs to pre-exercise their options in your infant stage startup. Then these rules are pretty moot. It takes advantage of people who don't have the money to pre-exercise options, who tend to be younger people.
Also it's unfair, investors can diversify their income sources, while employees cannot.
1. For a Linux user, you can already build such a system yourself quite trivially by getting an FTP account, mounting it locally with curlftpfs, and then using SVN or CVS on the mounted filesystem. From Windows or Mac, this FTP account could be accessed through built-in software.
2. It doesn't actually replace a USB drive. Most people I know e-mail files to themselves or host them somewhere online to be able to perform presentations, but they still carry a USB drive in case there are connectivity problems. This does not solve the connectivity issue.
3. It does not seem very "viral" or income-generating. I know this is premature at this point, but without charging users for the service, is it reasonable to expect to make money off of this?
While I understand there are moral and ethical complications with the vast sums of wealth and influence attached to RenTec, the tone in these comments is disappointing...
There is no fraud at RenTec, and there is nothing magical about what they do. It's simply an amazing technical and scientific organization, operating with almost unthinkable efficiency and scale.
I haven't read the book, but I'm pretty sure this isn't in it: I've been told by reliable sources that if you pick any one strategy (however you are able to separate/define that) from the Medallion portfolio and it will not be individually remarkable--probably less than a 1.0 Sharpe (net of trading costs, gross of fees). There are countless hedge funds with equally performant models and sub-strategies.
What makes RenTec different is their ability to generate orthogonal strategies at a remarkable scale. They generate more ideas with less philosophical and empirical overlap than anyone else, by a wide margin. The software and theory required to do this for a fund as large as Medallion is absolutely as rare and valuable as their returns have proven.
They probably have significantly better raw data sets than even their competitors like AQR or Two Sigma. Satellite data on parking lots. Credit card swipe statistics. Parsed and structures full financials. Supplier consumer relationships. Analyst data. Short interest data. Options activity. Fund holdings. ... Everything you can possibly think of. All integrated into a single streamline analytical and modeling technological infrastructure.
So yes to us little people it is insider trading. But I’m 99% sure it is real alpha at the core.
Yeah, just look at kdb+/q performance compared to Spark. The former is orders of magnitude more efficient and you realize that a cluster is only necessary because the performance and memory usage of the JVM is very poor on numerical workloads. Same goes for Hadoop.
The amount of money and engineering resources thrown at a problem that actually has a pretty simple solution (integrate your db and language, make your program and language runtime fit in L1 i-cache, optimize the hell out of your language) is a little disheartening. But hey, it keeps people employed managing and debugging an unholy mess of DBs, K8 clusters, load balancers, KV stores, and message brokers..
I was hoping this would be by Byrne Hobart! If you haven't checked it out, he writes daily at diff.substack.com and is up there with Ben Thompson and Matt Levine in terms of quality.
This is exactly what happened to Lightwave (a revolutionary 3D animation software). Management refused to allow the engineers to address pressing concerns so the chief engineer left to create another company whose products modo has now eclipsed Lightwave
https://youtu.be/DiOX-D2B8LE
I am pretty sure I have studied every interpretation and explanation of spinors and the non-simply-connectedness of SO(3) rotations, and I eventually finally understood it -- but, by ignoring explanations like the 'belt trick', rather than embracing them. I don't think this article makes it any better. As long as you're stuck on quaternions you're not going to be able to see what's going on, and the belt metaphor just adds complexity as well.
The version that currently makes the most sense to me is this:
* Quaternions are a complete distraction and should be ignored. i, j, and k are (xy), (yz), (zx) bivector rotation operators (up to a factor of -i or something like that). Pauli matrices are the same and should also be ignored.
* The factors of "theta/2" in the exponents that are used in representations of rotations using quaternions (rotating vectors with e^(R θ/2) v e^(-R θ/2)) are distracting and should be ignored.
* The best way to see what is meant by "the space of rotations in SO(3) is not simply connected", you need to think about paths in _rotation_ space carefully. More carefully than I did as an undergrad! (Although I'm sure this is obvious to people who have studied the approach math in a course?)
The wrong approach -- which I was stuck on for years -- is to think about a point on a sphere in R^3 moving around. A vector that starts at, say, +z in R^3 and is rotated by 2pi in the xz plane ends up where it started exactly.
The key insight is that 'non-simply-connectedness' refers to _paths of rotations_, rather than paths of what the rotations act on. So imagine gradually rotating that vector +z in the (xz) plane. If you go around by 2pi, you've made a path that can be modeled as an exponential operation: e^(2pi (z^x)).
The question is: can this path be deformed to the identity path? It seems like it can -- you just change from rotating +z all the way around a great circle, to a smaller and smaller circular path until it is just rotating in place (and xy rotation). But somehow when you collapse it, you still have a 2pi rotation! It's just that now it's a 2pi rotation in xy rather than in zx. No matter what you do, if you collapse the rotation path to be the identity on the +z vector, the resulting path rotates _some_ vector by 2pi, instead of keeping it at the identity.
So in physics, it's not that there is a negative phase factor _per se_ that matters for physics. It's that there are two physically distinguishable states (identity rotations and anti-identity rotations) -- so two different electron wave functions can't be identified as the same electron, because they are a 2pi rotation apart just due to how they got there. And the fact that we _model_ this is as a negative sign is entirely an artifact of our obfuscating choices of mathematics for the situation.
Half of the devs from there that I was in contact with were not capable of:
- googling a solution to a problem efficiently. When they hit a wall, they turned to me with an empty look like they were lost.
- read an error message to troubleshoot. A stack trace is utter mystery.
- use effectively the UI of their laptop. Some can't even Ctrl + S to save, they look up the "save" entry in the menu.
We are talking about people writing code every day, in several programming languages: fortran, c, c++, java, Python...
Because I'm a freelancer, I don't care. I'm paid extremely well to be very nice to them and solve all their problems.
But I'm very glad I don't have to be held responsible for anything those people end up putting in production. And I have no reason to believe it's different in their security department.
However, and this is a good lesson to all of the geeks like me that think work is about doing the right thing: the output they produce is good enough in our society. Its cost/value hits the sweat spot. Business is not about doing things right, it's about being profitable.
If you have one scandal a year, but it costs you less than making sure you have a secure system, and you are not legally challenged, then you are golden.
In fact, the chances to have even one scandal are very low. Actual risks of failure or attack are low. And consequences in case of crisis are low too. People don't care that much about privacy, cyber-security, etc. And policy makers won't enforce their laws anyway, at least not to any extent that will endanger the company.
So if the software allows people to do their job IRL at a reasonable price, under an acceptable deadline, good enough.
FreeCAD generally feels more like a traditional CAD program to me. I'd use OpenSCAD, but can't for my application: OpenSCAD fundamentally uses imprecise shape approximations. You draw a sphere but get a high-poly ball, sorta like raster vs vector in 2D imagery. This is fine for a lot of applications, but I want to CNC large, smooth undulating surfaces. The best way to get into my CNC (Shopbot PRS alpha) is via Fusion 360, and Fusion 360 barfs tremendously quickly with those high-poly shapes unless you get the actual (mathematical, "vector") shapes in with a format like IGES or STEP.
OpenSCAD is _awesome_ for targeting 3D printers, though.
- American Accent Training – it’s an audio book. Lots of great advice.
- Accent’s Way on YouTube. She’s an Israeli who taught herself the American accent to a complete perfection. You wouldn’t tell. Lots of information and motivation!