The Gig Economy and the ACS

This month I am beginning some new research on self-employment. There has been renewed interest in this topic due to technological advancement and the rise of the so-called "gig economy," but measuring it has been an empirical challenge. Thus I happy to share a figure I created, using data from the American Community Survey (ACS), that shows a very noticeable "Uber" effect:

Figure: Fraction of Workers in Taxi and Limousine Industry who are Self-employed (and unincorporated) in the ACS

Research data for The Impact of Urban Form on Vehicle Ownership

One of the attractive features of the ACS data is the ability to ask several types of transportation questions, to millions of Americans. I exploit this fact in my new research results on the effect of land use patterns on vehicle demand. This article is forthcoming in the journal Economics Letters.

The data and code for this study are hosted at Open ICPSR. The Inter-University Consortium for Political and Social Research was conceived in the 1960s as a place where universities share data, and has thus been in the data game for a long time. In the past their data archiving has been more curated, and the new "Open" ICPSR is a new and exciting development. I plan to continue to use OpenICPSR to archive the research data for my projects.

Downloading Census Micro Data: IPUMS or Census.gov?

My current book project reviews studies that use the American Community Survey (ACS) micro data in a way that sheds relevant light on contemporary social controversies, illustrates best statistical practices, or both.

Most of the studies I include in the book use data from a database at the University of Minnesota called "IPUMS" (which stands for The Integrated Public Use Microdata Series.) It is also possible, at least for some years, to directly download the ACS data from the Census.gov web page. Which option is preferable?  In this post I provide some answers to this question, as well as share a data file illustrating all the variables available by directly downloading the ACS data from the Census.gov webpage.

Replicating Costa and Kahn (2011), part II

In my last two posts here and here, I discussed a reproduction and replication of Costa and Kahn's (2011) study on electricity consumption by California households. The difference between the two previous posts is that in one I used data supplied by the authors, and in the other I used data that I downloaded from IPUMS-USA, a publicly-available source. In this post I am reporting new estimates of the same model, but using the most recent data from the 2012-2017 American Community Survey.

Replicating Costa and Kahn (2011)

In my last post, I described how I reproduced the analysis of Costa and Kahn (2011) which was originally done in Stata, using the R programming language.  There I said I'm calling it a reproduction because, even though I was using different software, I was using the author-provided data.

A different question I address in this post is, can their results be replicated using what should be the same data obtained from a different source? It turns out it can and my R script is available here. This is a relevant question because for example sometimes data sets are updated (e.g. if errors are discovered). In addition, the data supplied by Costa and Kahn is only a small subset of the 2000 Census data, which only contains California homeowners in single-family homes. This is enough to reproduce their results, but it severely limits the types of extensions that one can do with their data (for example, if one wanted to estimate the baseline model on Florida households or for households in multi-family housing.)

Reproducing Costa and Kahn (2011) in R

I just produced this R script that reproduces the results presented in the 2011 paper, "Electricity Consumption and Durable Housing: Understanding Cohort Effects" by Dora Costa and Matt Kahn.

The first result from my current replication book project

 I am sharing data and replication files I wrote for an article published in 2016 by John V. Winters titled, “Is economics a good major for future lawyers? Evidence from earnings data,” here on my blog. The replication files are at the bottom of this page. This is the first time I’ve produced and shared replication files, but over the next year, I hope to add replication files for an additional 10-15 more previously published studies.

 

Update December 3, 2020: Please visit the finished book's companion site for all data and code files.  

 

Where is the City's Center? On the Recent use of Measures of Central City Location

The title of this post is taken from a manuscript I just wrote and hope to have published soon. [Update: it is now published and available here] I will update this blog article with a link to that article once it is finished, but I am posting this now because I wanted to share the data and analysis file I used in writing the article.

The XLSX file is here.

The Economics of a Border Wall

A recent study by economists Treb Allen, Melanie Morten and Caue Dobbin (2018) is not yet published but has already has received much publicity. The authors study the economic impacts of the border fences that already exist on the US-Mexico border. The authors write: