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nepstein

328 karma · joined August 8, 2014

Applied Math @Columbia BS'13, MS'15. @recursecenter W2'15
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nepstein··on Functional programming in C++
I'm not sure I agree that STL that containers are explicitly not OO.

That said, I don't disagree that C++ can support functional programming. I would just argue there are languages better suited for this.

(edited for clarity)

nepstein··on Functional programming in C++
Nice article and effective demonstration of the FunctionalPlus library.

That said, this makes me a bit nervous about shoe-horning functional programming into contexts where it is inappropriate. FunctionalPlus aside, C++ is very clearly designed for an object oriented style (even the name, C++, refers to "C plus objects").

Going too far down the path of working against the intent of the standards committee seems like a recipe for trouble (unless you're just talking about hobby projects).

nepstein··on Five Years of Recurse Center
Just to clarify, there is no direct cost associated with RC. It is free to attend for all participants. Grants, for those who qualify, are for living expenses.

That said, 3 months of wages is still a prohibitive cost for many would-be participants.

nepstein··on Women Who Code (YC S16) helps female engineers level up in their careers
It's a charitable donation - https://www.ycombinator.com/nonprofits/
nepstein··on It’s a Tough Job Market for the Young Without College Degrees
If you're finding part-time study too slow, there are a number of non-academic contexts in which you can study code full time.

Despite the reputation, there are some web-dev bootcamps that have good placement rates.

A few in the US: 1) http://www.fullstackacademy.com/ 2) http://www.hackreactor.com/ 3) http://flatironschool.com/

If you're a woman, there's the deferred tuition (no charge until you have a job) option:

http://www.gracehopper.com/

Or if you're not interested in a bootcamp, but rather a self directed environment surrounded by a community of other developers (and want a free option) there's Recurse Center (https://www.recurse.com/)

nepstein··on ROI on a college degree depends what you study, not where
Worth noting that selective schools also tend to be more expensive. Even if the ROI isn't markedly higher, high price tag means a "larger investment" into the high ROI option of college education.

That's a substantive advantage (to those that can afford it) given that 12% return opportunities are scarce.

nepstein··on Deep Learning Is Going to Teach Us All the Lesson of Our Lives
AI => automation => unemployment => basic income

That basic argument makes sense to me but the leap to say that AlphaGo proves automation is accelerating doesn't.

Go is one of many task-specific AI's. It's not clear that it implies anything about generalized AI (which most experts agree is still very far off) or the rate at which task-specific AI's are developed.

nepstein··on The Mathematics of Paul Graham's Bias Test
True - though this means only that the signal (outperformance by a group that is the target of discrimination) might not be present (if discrimination continues past initial selection as you point out).

However, the test may still useful to help confirm bias. If outperformance is observed, you can infer one of 3 things is true:

1) there is bias at initial selection but not after (or at least reduced bias)

2) members of the outperforming group are simply stronger performers (different but still interesting)

3) there is no bias at selection but there are affirmative action effects after the initial selection (not obvious why this would be the case)

nepstein··on Drug Goes from $13.50 a Tablet to $750, Overnight
Ah, should've given it a closer look! Apologies for the mixup.
nepstein··on Drug Goes from $13.50 a Tablet to $750, Overnight
UPDATE: the price increase has been rescinded

http://www.nytimes.com/2015/09/22/business/big-price-increas...

nepstein··on Ask HN: Who is hiring? (July 2015)
Wealthsimple - https://www.wealthsimple.com - Toronto, ON

We're on a mission to make investing smarter and simpler for everyone. We develop algorithms to track, manage, and rebalance client portfolios.

We're currently hiring Full-Stack Web Developers, iOS Developers, and Android Developers: https://www.wealthsimple.com/jobs

We push code (after review!) to production several times a day and are working on some cool technical challenges like building a scalable trade execution platform, automating portfolio rebalancing, and automated tax-loss harvesting. We use modern technologies like: Ruby on Rails, Backbone.js, SASS, PostgreSQL running on Heroku.

Contact: jobs@wealthsimple.com

nepstein··on Pavlov.js – Reinforcement learning using Markov Decision Processes
The README links to a blog post (http://nepste.in/jekyll/update/2015/02/22/MDP.html) which details how the library is implemented from the definition of a MDP.

For a more rigorous treatment, Andrew Ng's notes (http://cs229.stanford.edu/notes/cs229-notes12.pdf) are an excellent resource.

nepstein··on Pavlov.js – Reinforcement learning using Markov Decision Processes
I can definitely understand wanting to classify Pavlov as supervised learning. I think it's a murky issue because supervised and reinforcement are very closely related (and it is frequently possible to reframe problems of one type as problems of the other depending on what type of model one uses).

My two main reasons for going with this name are as follows (if people see issues in my logic, I'm happy to be convinced):

1) Reinforcement learning gets its name from the behaviorist psychology concept of reinforcement in which an agent's actions are met with rewards in order to shape that agent's future behavior. This is precisely the kind of response conditioning that Pavlov is well known for.

2) The key difference is what the training data look like.

In a supervised learning problem, the training data are input/output pairs (a stimulus and an appropriate action).

In reinforcement learning, the training data are input and reward pairs (an action and the reward applied to that action).

I would argue that Pavlov's experiments more like the latter case - the dogs are not shown 'this is the correct action for this stimulus', they are shown 'this is the reward for this stimulus'.

nepstein··on Show HN: Markov – A compact C++ library to easily simulate Markov processes
fixed, thanks
nepstein··on “How to Start a Startup” Audio Files
Turns out Dropbox was a bad choice. The links were disabled for generating too much traffic. The files are now hosted on archive.org and the Github repo has been updated.
nepstein··on “How to Start a Startup” Audio Files
To avoid the issue of hosting large files on Github - the repo now links to remote downloads of the lectures (from dropbox).
nepstein··on Show HN: Stochastic – JavaScript library for simulating stochastic processes
Good call, thank you. Updated version has been republished.
nepstein··on Show HN: Stochastic – JavaScript library for simulating stochastic processes
It looks like you're referring to the (equivalent) polar form. I'm using the 'Basic Form'.

http://en.wikipedia.org/wiki/Box%E2%80%93Muller_transform#Ba...