Federal Reserve Bank of NY converts major economic model to Julia • Hacker News Board

Re: Federal Reserve Bank of NY converts major economic model to Julia

#41

Post by lawpoop » Thu, Dec 03, 2015, 8:14 PM UTC

kolbe wrote: post #32

burke wrote: post #28

Earlier quoted context omitted.

I haven't either, but they just start with a #, right? What's the problem? EDIT: Oh, I see there are multiline comments.

I see things that look a lot like english sentences that are neither preceded by #, nor surrounded by #= =#. edit: with examples. this code, all the way up to line 48 looks like some comments, but also a bunch of sentences without the comment characters. https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/...

I the example you link, it looks like the top half is all comments, starting with """ on a line, and ending with """ on a line. What's confusing is that code examples in the comments are surrounded by ```, and they are long enough to look like actual code.

Also, in this markup, the top comments are blue only.

Then, the actual code begins, and it is syntax-colored. In code, comments seem to be preceded by pound.

After a big chunk of code, there is another set of comments in """, and then some more code, ending with `end`.

The ``` code samples in the comments might be part of some automated comment documentation extraction standard or some markup convention. The comments near them seem very formal, defining or explaining the code.

That's the best I can do not knowing the language.

Re: Federal Reserve Bank of NY converts major economic model to Julia

#42

Post by neffy » Thu, Dec 03, 2015, 8:28 PM UTC

danso wrote: post #13

For those of you in this field...how influential is the NYFed trying out (and apparently being satisfied with) Julia to other government agencies, computational economists, and/or academics? Is it "OS X is Unix/BSD-based" influential, or "Whitehouse.gov uses Drupal [1]" influential? [1] http://buytaert.net/whitehouse-gov-using-drupal

The DSGE models are influential up until somebody comes up with a valid alternative, at which point they will be dropped at somewhat over the speed of light :)

To be brutally honest, this is not a big achievement. You should be able to rapidly speed up any matlab model by porting it into pretty much any other language due to well known issues with matlab. Being able to run DSGE models more quickly is important to economists because it allows them to be better 'callibrated' - which is to say that the economists essentially tweak the models for the country they are looking at, until they fit the known data over an acceptable time period. (They don't try to hide this btw. there are scores of papers on model calibration approaches.)

A good example of what this leads to is the one for Iceland:

http://www.sedlabanki.is/lisalib/getfile.aspx?itemid=8077

Notice that this is published in 2010, but for some strange reason the charts (p57 onwards) all stop in 2005.

It's over fitting to the curve on computer assisted steroids.

Re: Federal Reserve Bank of NY converts major economic model to Julia

#43

Post by josu » Thu, Dec 03, 2015, 8:40 PM UTC

otoburb wrote: post #36

josu wrote: post #23

Earlier quoted context omitted.

This is an anecdote about a big Matlab proponent who switched sides. I learned Matlab from my Econ 101 professor 8 years ago. He was a big Matlab proponent, and he knew all the econ tools inside out. We kept in touch, since he has been one of the best professors I've ever had. So, fast forward to 2 years ago, I sent him an email asking about this [1] Quantitative Economics course by Sargent and Stachurski based on py…

>>He also told me to get away from the Sargent and Stachurski course, that they add too much complexity to the explanations just for the sake of looking more Nobel-prize-winner like. That's really good feedback for anybody thinking of attempting that course. Does your professor recommend an accompanying course to Sargent and Stachurski's quantitative economics course? I haven't seen many other courses that provide co…

Nope, I'm sorry, he just told me that I should get into Python. He did recommend this edX course, but it's an introduction to Python, nothing to do with economics.

[1] https://www.edx.org/course/mitx/mitx-6-00-1x-introduction-co...

Re: Federal Reserve Bank of NY converts major economic model to Julia

#44

Post by nextos » Thu, Dec 03, 2015, 8:44 PM UTC

How's the probabilistic programming use case in Julia now?

I don't like Python as a language that much (I prefer Lisps or MLs), but I reckon its libraries are fantastic: PyMC, Theano, NumPy... And loads of general-purpose stuff.

Re: Federal Reserve Bank of NY converts major economic model to Julia

#45

Post by has2k1 » Thu, Dec 03, 2015, 8:50 PM UTC

I like the use of the Greek alphabet in the code base.

Examples

https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/...

Re: Federal Reserve Bank of NY converts major economic model to Julia

#46

Post by cauthon » Thu, Dec 03, 2015, 9:01 PM UTC

has2k1 wrote: post #45

I like the use of the Greek alphabet in the code base. Examples https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/... https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/...

Whoa that's awesome, are there any other languages that allow that?

Re: Federal Reserve Bank of NY converts major economic model to Julia

#47

Post by purpleparakeet » Thu, Dec 03, 2015, 9:05 PM UTC

cauthon wrote: post #46

has2k1 wrote: post #45

I like the use of the Greek alphabet in the code base. Examples https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/... https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/...

Whoa that's awesome, are there any other languages that allow that?

Swift.

Re: Federal Reserve Bank of NY converts major economic model to Julia

#48

Post by martinflack » Thu, Dec 03, 2015, 9:09 PM UTC

cauthon wrote: post #46

has2k1 wrote: post #45

I like the use of the Greek alphabet in the code base. Examples https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/... https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/...

Whoa that's awesome, are there any other languages that allow that?

Common Lisp

Re: Federal Reserve Bank of NY converts major economic model to Julia

#49

Post by lg » Thu, Dec 03, 2015, 9:09 PM UTC

cauthon wrote: post #46

has2k1 wrote: post #45

I like the use of the Greek alphabet in the code base. Examples https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/... https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/...

Whoa that's awesome, are there any other languages that allow that?

lots: http://rosettacode.org/wiki/Unicode_variable_names

Re: Federal Reserve Bank of NY converts major economic model to Julia

#50

Post by bcg1 » Thu, Dec 03, 2015, 9:24 PM UTC

cauthon wrote: post #46

has2k1 wrote: post #45

I like the use of the Greek alphabet in the code base. Examples https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/... https://github.com/FRBNY-DSGE/DSGE.jl/blob/master/src/solve/...

Whoa that's awesome, are there any other languages that allow that?

Java