Profile picture
, 5 tweets, 2 min read
Hey #econtwitter- I'm helping put together a tip sheet re computational tools for structural IO, including notes on when some languages/solvers are better than others. I don't use python for optimization but I know lots of ppl do. Any chance y'all could lend some tips? Example 👇
A few other things that it'd be great to have a 1-liner explaining (w/ links to more):
-How to evaluate trade-offs re Analytical Derivatives vs Numerical Differentiation vs Auto Differentiation
-When to impose optimizer constraints via transformation -- e.g., mapping [0,1] -> R
Here's my draft so far. Plz send more tips/correct any errors.
I wrote a bit about R too.
What are some downsides of python? @conlon_chris @alex_peys
Missing some Tweet in this thread? You can try to force a refresh.

Enjoying this thread?

Keep Current with Shosh Vasserman

Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!

Twitter may remove this content at anytime, convert it as a PDF, save and print for later use!

Try unrolling a thread yourself!

how to unroll video

1) Follow Thread Reader App on Twitter so you can easily mention us!

2) Go to a Twitter thread (series of Tweets by the same owner) and mention us with a keyword "unroll" @threadreaderapp unroll

You can practice here first or read more on our help page!

Related hashtags

#econtwitter

More from @shoshievass see all

Profile picture
Shosh Vasserman
@shoshievass
Day 2 of #NBERSI starts w an IV approach to estimation in dynamic models
papers.nber.org/conf_papers/f1…

Motivation: Historically, structural dynamic models treat mkt structure (eg serial correlation) as exogenous --> Propose an IV approach for ID, allowing for endogenous mkt structure
-"standard" IO practice for conditional choice probability models (ccps) assume unobservables are IID + privately known
- Disallowing serial correlation in (e.g.) state shocks is very restrictive
- Prev literature has proposed different solutions
--> But no 'general' approach
- (G)IV approach: modify 1st step of CCP to identify policy fns w/ IVs
- Which IVs? e.g. past exog variation & demand/cost shifters
- How? Construct moments interacting necessary conditions of the (more flex) dynamic model w/ IVs. More Informative IV -> tighter ID on choice probs
Read 10 tweets
Profile picture
Shosh Vasserman
@shoshievass
As promised, a live-tweeting of “Instrument-Free Demand Estimation” by Alexander MacKay and Nathan Miller at the IO session of #nbersi papers.nber.org/conf_papers/f1…
The elevator pitch: A classic challenge in estimating demand is price endogeneity: consumer demand for goods varies w/ the menu of prices, but that menu adjusts to demand.
Typical approaches to deal with this: (1) moment-based estimation + IVs; (2) likelihood estimation w/ parametric assumptions on the co-movement of price + demand
Read 16 tweets

Related threads

Profile picture
Dina D. Pomeranz
@DinaPomeranz
#EconTwitter Important question of broad interest: What should potential econ PhD applicants make of the info that depression is high among grad students, and worries about whether this will be a path that ends up being fulfilling to them?

#EconAdvice
A few thoughts, but looking forward to hearing from others:

1) Don't do an econ PhD for the title. It's too long and intense for that. Do it only if you are interested in doing research and see the PhD process itself as a job that you might enjoy.
2) Many experience 1sr year (i.e. 8 months) as the worst, but then with field classes and research it gets closer to what you enjoy. Once in, dont quit because you don't enjoy the first year, that is not at all representative of how the rest will be.
Read 13 tweets
Profile picture
Stu Cvrk
@STUinSD
Thread: More on that Global Hawk Shot Down by the Iranians – Lies and Damn Lies

1. Iranian apologists are out in force trying to defend the IRGC’s shoot-down of a US RQ-4 Global Hawk Unmanned Aircraft System (UAS) on Thursday.
2. BTW, here’s what the manufacturer says about the aircraft; well worth a look if you don’t know what it is or can do:
northropgrumman.com/Capabilities/G…
3. In “dueling diplomatic statements,” Iran and the US have made quite different official statements on what transpired. An IRGC general took credit for the shoot-down, claiming that the RQ-4 was “inside Iranian airspace.”

<quote>
Read 50 tweets
Profile picture
Patrick Kennedy
@kennedy_patk
Hey there, #econtwitter. Today in my first-ever tweet I am happy to share my new working paper about the ~Global Trade War~ with Pablo Fajgelbaum, @Penny_WB , and Amit Khandelwal. Paper here, and full thread of charts and takeaways to follow >> econ.ucla.edu/pfajgelbaum/RT…
1/N

First, the basics. In 2018 the US imposed steep tariff increases on more than 12,000 import products, worth ~$300 billion annually.

In response, trade partners retaliated with steep tariff increases on more than 3,000 US export products, worth ~$100 billion annually.
2/N
Our study detects large and immediate impacts of these tariffs on trade flows.

We estimate that, on average, the value of targeted US imports declines ~30% in response to the tariffs...
Read 18 tweets
Profile picture
Jess Hoel
@Jess_Hoel
Hey #EconTwitter, THE (preliminary) RESULTS ARE IN!

Is cash fungible?

Do people exhibit the same risk and time preferences when offered money in cash or money in Venmo?

Do people exhibit the same risk and time preferences over round numbers and pennies?
No, No, and No.
Some background: In the second half of my experimental class, we designed, ran, (quickly) analyzed, and today we presented a new experiment. I pitched my idea 13 days ago. The students pitched theirs 11 days ago. We voted. One of their ideas won.

Read 20 tweets
Profile picture
Jeff McFadden
@homemadeguitars
Y'all, I need a night off.
Ya wanna hear everything I know about the pedal steel guitar? Do you play guitar? We'll start there. -more
2. The way you play notes on a guitar is, you make the strings shorter with your fingers. The lowest note on any string is that string with no fingers on it. If you didh't have a fretboard you'd be playing the harp. Each different note is a different length string.
3. And the way you make pleasing chords is you shorten the various strings to lengths which sound harmonious together. If you play you know the positions, C and D and E, so forth.
Read 42 tweets
Profile picture
Aaron Hall, 🐍 Professor, NYC, 🇺🇸
@aaronchall
High level #python #tutorial thread:
Python is a high level language that runs bytecode in its virtual machine.
Everything is an object.
It supports OOP up to multiple inheritance and functional programming.
Typing is polymorphic - duck typing is preferred
A Python script is a file with a name like name.py - we indent at four spaces (it matters), comments (after #) don't execute - and is typically written like:

def main(): # function
print("Hello world")

if __name__ == '__main__': # then entry point
main()
A module is a reusable script:

"""this is a docstring at the top of the module - gives help on the module"""

import this # do imports at the top

def main(): # main at top or bottom
"""functions get docstrings too"""

if __name__... always at the bottom, assumed from now on
Read 68 tweets

Trending hashtags

#ReplicationCrisis #CloudSQL #PakBrilliance #BigQuery #CEA2019 #EconReplicationCrisis #AWS #EconTwitter #metoo #python #Pakistan #climatechange #finlit #childrights #econtwitter #EconometricsTwitter #IWD2018 #deathpenalty #RCT #MySQL #datastudio #WhyPython #Takebackthetech #GoogleSheets #violenceagainstwomen
Follow Us on Twitter!

Did Thread Reader help you today?

Support us! We are indie developers!

This site is made by just three indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3.00/month or $30.00/year) and get exclusive features!

Become Premium

Too expensive? Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal Become our Patreon

Thank you for your support!