Constitutional Forks Revisited

Around this time last year, we discussed the idea of a constitutional “fork” that occurred with the founding of the Confederate States of America. That post briefly explains how forks work in open source software and how the Confederates used the US Constitution as the basis for their own, with deliberate and meaningful differences. Putting the two documents on Github allowed us to compare their differences visually and confirm our suspicions that many of them were related to issues of states’ rights and slavery.

Caleb McDaniel, a historian at Rice who undoubtedly has a much deeper and more thorough knowledge of the period, conducted a similar exercise and also posted his results on Github. He was faced with similar decisions of where to obtain the source text and which differences to retain as meaningful (for example, he left in section numbers where I did not). My method identifies 130 additions and 119 deletions when transitioning between the USA and CSA constitutions, whereas the stats for Caleb’s repo show 382 additions and 370 deletions.

What should we draw from these projects? In Caleb’s words:

My decisions make this project an interpretive act. You are welcome to inspect the changes more closely by looking at the commit histories for the individual Constitution files, which show the initial text as I got it from Avalon as well as the changes that I made.

You can take a look at both projects and conduct a difference-in-differences exploration of your own. More generally, these projects show the need for tools to visualize textual analyses, as well as the power of technology to enhance understanding of historical and political acts. Caleb’s readme file has great resources for learning more about this topic including the conversation that led him to this project, a New York Times interactive feature on the topic, and more.

Political Forecasting and the Use of Baseline Rates

As Joe Blitzstein likes to say, “Thinking conditionally is a condition for thinking.” Humans are not naturally good at this skill. Consider the following example: Kelly is interested in books and keeping things organized. She loves telling stories and attending book clubs. Is it more likely that Kelly is a bestselling novelist or an accountant?

Many of the “facts” about Kelly in that story might lead you to answer that she is a novelist. Only one–her sense of organization–might have pointed you toward an accountant. But think about the overall probability of each career. Very few bookworms become successful novelists, and there are many more accountants than (successful) authors in the modern workforce. Conditioning on the baseline rate helps make a more accurate decision.

I make a similar point–this time applied to political forecasting–in a recent blog post for the blog of Mike Ward’s lab (of which I am a member):

One piece of advice that Good Judgment forecasters are often reminded of is to use the baseline rate of an event as a starting point for their forecast. For example, insurgencies are a very rare event on the whole. For the period January, 2001 to August, 2013, insurgencies occurred in less than 10 percent of country-months in the ICEWS data set.

From this baseline, we can then incorporate information about the specific countries at hand and their recent history… Mozambique has not experienced an insurgency for the entire period of the ICEWS dataset. On the other hand, Chad had an insurgency that ended in December, 2003, and another that extended from November, 2005, to April, 2010. For the duration of the ICEWS data set, Chad has experienced an insurgency 59 percent of the time. This suggests that our predicted probability of insurgency in Chad should be higher than for Mozambique.

I started writing that post before rebels in Mozambique broke their treaty with the government. Maybe I spoke too soon, but the larger point is that baselines are the starting point–not the final product–of any successful forecast.

Having more data is useful, as long as it contributes more signal than noise. That’s what ICEWS aims to do, and I consider it a useful addition to the toolbox of forecasters participating in the Good Judgment Project. For more on this collaboration, as well as a map of insurgency rates around the globe as measured by ICEWS, see the aforementioned post here.

Visualizing Political Unrest in Egypt, Syria, and Turkey

The lab of Michael D. Ward et al now has a blog. The inaugural post describes some of the lab’s ongoing projects that may come up in future entries including modeling of protests, insurgencies, and rebellions, event prediction (such as IED explosions), and machine learning techniques.

The second post compares two event data sets–GDELT and ICEWS–using recent political unrest in the Middle East as a focal point (more here):

We looked at protest events in Egypt and Turkey in 2011 and 2012 for both data sets, and we also looked at fighting in Syria over the same period…. What did we learn from these, limited comparisons?  First, we found out first hand what the GDELT community has been saying: the GDELT data are in BETA and currently have a lot of false positives. This is not optimal for a decision making aid such as ICEWS, in which drill-down to the specific events resulting in new predictions is a requirement. Second, no one has a good ground truth for event data — though we have some ideas on this and are working on a study to implement them. Third, geolocation is a boon. GDELT seems especially good a this, even with a lot of false positives.

The visualization, which I worked on as part of the lab, can be found here.  It relies on CartoDB to serve data from GDELT and ICEWS, with some preprocessing done using MySQL and R. The front-end is Javascript using a combination of d3 for timelines and Torque for maps.


GDELT (green) and ICEWS (blue) records of protests in Egypt and Turkey and conflict in Syria

If you have questions about the visualizations or the technology behind them, feel free to mention them here or on the lab blog.

Podcasts I Like

Apologies for the silence here lately. I have been working on a couple of longer-than-average posts, as well as some fun projects that I will hopefully be able to share with you here soon. Part of the influence in those upcoming posts is from podcasts I have enjoyed. (Readers of the tipping post may have noticed that two of the main references there were to podcasts as well.)

Ben Franklin Koss HeadphonesThus, I thought readers of this blog might enjoy some of my favorites. There are likely some that I have omitted because I listened to all of their episodes some time ago. Below are those that have stood the test of time or that I am listening to currently.

Economics/Social Science

  • Analysis: Half-hour episodes on current events with a social scientific perspective.
  • Data Stories: As you might expect, an audio podcast about data visualization has some weak points. However, this is useful as a who’s-who of the visualization community.
  • Econtalk: My absolute favorite podcast. Each week, Russ Roberts and a guest discuss research or current events using economics as a lens on the world. Sometimes I think Russ is too hard on statistical methods, but every episode is worth a listen.
  • Great Economists: Originally a MOOC from MRUniversity, the audio from this course is now available as a condensed series of podcasts.
  • History of Rome: History’s greatest empire in 170-odd episodes. Although new episodes are no longer being produced, host Mike Duncan has a new project in the pipeline that is expected in September.
  • Loopcast: DC WarKids and their guests discuss national security and international relations.
  • More or Less: Tim Harford takes quantitative headlines and questions them, often finding more than meets the eye.
  • Planet Money: My second-favorite podcast, after Econtalk. The hosts explain current events or applied economics lessons in accessible language with fun examples. A podcast like this focused on politics would immediately become my all-time favorite.
  • Pop-Up Ideas: Another Tim Harford podcast, this one covers big ideas in social science in a short and punchy manner.


  • Accidental Tech Podcast: Marco Arment, Casey Liss, and John Siracusa discuss Apple and web technology. This podcast originated as outtakes of their casual car show, Neutral. A very enjoyable listen every week.
  • Bitsplitting: Daniel Jalkut  interviews technology professionals, many of them entrepreneurs.
  • CMD+Space: Myke Hurley interviews guests who “do great things.”
  • Giant Robots Smashing into Other Giant Robots: Discussions of software design and development, hosted by Thoughtbot’s Ben Orenstein.
  • Ruby Rogues: Although originally a Ruby-focused program, after over 100 episodes the rogues now delve into other issues including education, cognition, and the politics of software communities.

Currency and Conflict

According to Lebanon’s Daily Star:

Traders across Syria reported widely fluctuating rates and two currency dealers in Damascus, where the pound appeared to be hit hardest, said it fell below 200 to the dollar for the first time in what one described as panic buying of the U.S. currency.

On Monday evening the pound traded at 205 to the dollar, down 20 percent in four days and 77 percent down since the start of the anti-Assad uprising in March 2011 when it was at 47.

The idea of examining currency prices over the course of a conflict is interesting. There are a number of confounders of course. For instance, the regime can often intervene in certain ways to affect the value of currency. Other incidents besides the conflict itself can also drive currency fluctuations, especially when the conflict is relatively minor.

One nice case (from strictly a research perspective) is the US Civil War, when both the Union and Confederacy issued their own notes. Jeffrey Arnold‘s project, “Pricing the Costly Lottery: Financial Market Reactions to Battlefield Events in the American Civil War,” leverages this fact to see how markets responded to successes and failures of either side. We discussed this project before when it was presented as a poster at PolMeth 2012, and Jeffrey’s website now has his MPSA 2013 slides.

Here’s his abstract, and one of my favorite graphs:

What role does combat play in resolving the disagreement that initiated war? Bargaining theories of war propose two mechanisms, the destruction of capabilities and the revelation of private information. These mechanisms are difficult to analyze quantitatively because the mechanisms are observationally equivalent, the participants’ expectations are unobservable, and there is a lack of data on battles. With new methods and new data on the American Civil War, I address these challenges. I estimate the information revealed by combat with a model of Bayesian learning. I use prices of Union and Cnnnonfederate currencies to measure public expectations of war duration and outcome. Data on battlefield events come from detailed data on the outcomes and casualties of the battles of the American Civil War. The results suggest that battle outcomes rather than casualties or information revelation had the largest influence on the expected duration of the American Civil War.


Mapping Literal Place Names

Place names are another one of those micro-institutions. They often carry a linguistic legacy indicating some important discoverer, inhabitant, or conqueror. Changes in place names are significant too. (Would Sinatra’s “New Amsterdam, New Amsterdam” have rolled off the tongue nearly as nicely?) As the names accumulate history and new generations become accustomed to them, however, we often lose the literal sense of their meaning. In an effort to help undo that, the Atlas of True Names “reveals the etymological roots, or original meanings,of the familiar terms on today’s maps of the World, Europe, the British Isles and the United States.”

Here are a couple of examples, and there is much more at the link:



Risk, Overreaction, and Control

11-M_El_How many people died because of the September 11 attacks? The answer depends on what you are trying to measure. The official estimate is around 3,000 deaths as a direct result of hijacked aircraft and at the World Trade Center, Pentagon, and in Pennsylvania. Those attacks were tragic, but the effect was compounded by overreaction to terrorism. Specifically, enough Americans substituted driving for flying in the remaining months of 2001 to cause 350 additional deaths from accidents.

David Myers was the first to raise this possibility in a December, 2001, essay. In 2004, Gerd Gigerenzer collected data and estimated the 350 deaths figure, resulting from what he called “dread risk”:

People tend to fear dread risks, that is, low-probability, high-consequence events, such as the terrorist attack on September 11, 2001. If Americans avoided the dread risk of flying after the attack and instead drove some of the unflown miles, one would expect an increase in traffic fatalities. This hypothesis was tested by analyzing data from the U.S. Department of Transportation for the 3 months following September 11. The analysis suggests that the number of Americans who lost their lives on the road by avoiding the risk of flying was higher than the total number of passengers killed on the four fatal flights. I conclude that informing the public about psychological research concerning dread risks could possibly save lives.

Does the same effect carry over to other countries and attacks? Alejandro López-Rousseau looked at how Spaniards responded to the March 11, 2004, train bombings in Madrid. He found that activity across all forms of transportation decreased–travelers did not substitute driving for riding the train.

What could explain these differences? One could be that Americans are less willing to forego travel than Spaniards. Perhaps more travel is for business reasons and cannot be delayed. Another possibility is that Spanish citizens are more accustomed to terrorist attacks and understand that substituting driving is more risky than continuing to take the train. There are many other differences that we have not considered here–the magnitude of the two attacks, feelings of being “in control” while driving, varying cultural attitudes.

This post is simply meant to make three points. First, reactions to terrorism can cause additional deaths if relative risks are not taken into account. Cultures also respond to terrorism in different ways, perhaps depending on their previous exposure to violent extremism. Finally, the task of explaining differences is far more difficult than establishing patterns of facts.

(For more on the final point check out Explaining Social Behavior: More Nuts and Bolts for the Social Sciences, which motivated this post.)

Blogging, Two Years On

Tuesday marked the second anniversary of YSPR. I wrote the first post while at a political science conference, so it seems fitting that I spent the last couple of weeks travelling to ISA and MPSA. From those two conferences it is clear that blogging and social media are playing an increasingly prominent role in the field. At ISA there was a strong turnout for the blogging reception. While in Chicago for MPSA I had the pleasure of joining a dinner for conflict scholars hosted by Will Moore and Christian Davenport. One notable aspect of that dinner was that in the invitation email everyone had a personal website or blog.

I sincerely appreciate everyone who has visited this blog over the past two years and expressed their support either online or in person. For others who may be starting a blog or thinking about doing so, here are a few lessons I have learned over the past year:

1. Schedule your writing. Making time to write is an important habit to get into. Whether it’s daily or weekly, set aside some time that you can avoid distractions and just write. I usually like first thing in the morning, but you may prefer late evening or another time of day.

2. Schedule your posts. I used to hit “publish” as soon as I wrote something, but that changed this year. Instead, I like to line up about a week’s worth of posts at a time. This allows me to arrange some continuity between posts. It also gives time for my ideas to gel and to ruminate over new post ideas without feeling rushed (and sometimes catch typos).

3. Get involved in a community of writers. Blogging can feel like a solitary task, but it doesn’t have to be. A year ago I got in touch with Duke professor Marc Bellemare since I enjoy his blog. We now get lunch or coffee occasionally and chat about all manner of interesting topics. There are also a few scholar-bloggers I know primarily through blogs and Twitter (Jay Ulfelder, Trey Causey).  Creating friendships with people who will respond to your writing and offer critique when you need it is invaluable.

Thanks for being part of the conversation!

Communication Technology and Politics

Cell phone coverage (black) and conflict locations (grey) in Africa (Pierskalla and Hollenbach, 2013: Fig. 1)

Cell phone coverage (black) and conflict locations (grey) in Africa (Pierskalla and Hollenbach, 2013: Fig. 1)

We have been on a technology kick this week, first talking about modern etiquette and then how technology improved traffic in LA. Today I want to point out two neat papers at the intersection of communication technology and politics.

The first article deals with “narrowcasting”-type technologies. Pierskalla and Hollenbach (2013) analyze the association between cell phone coverage and conflict in Africa.* They use 55×55 km grid cells rather than the more conventional country-year observational units for their analysis. Here’s the abstract:

The spread of cell phone technology across Africa has transforming effects on the economic and political sphere of the continent. In this paper, we investigate the impact of cell phone technology on violent collective action. We contend that the availability of cell phones as a communication technology allows political groups to overcome collective action problems more easily and improve in-group cooperation, and coordination. Utilizing novel, spatially disaggregated data on cell phone coverage and the location of organized violent events in Africa, we are able to show that the availability of cell phone coverage significantly and substantially increases the probability of violent conflict. Our findings hold across numerous different model specifications and robustness checks, including cross-sectional models, instrumental variable techniques, and panel data methods.

Another neat paper I came across recently deals more with broadcasting technologies. Adena et al (2013) explore the association between radio broadcasts in pre-war Germany and pro- or anti-Nazi sentiment. The identification strategy is rather simple: before the Nazi party took power, radio broadcasts were anti-Nazi. That changed in 1933 when the Nazis took over. According to their paper it took a very short time for sentiments to change:

How far can media undermine democratic institutions and how persuasive can it be in assuring public support for dictator policies? We study this question in the context of Germany between 1929 and 1939. Using quasi-random geographical variation in radio availability, we show that radio had a significant negative effect on the Nazi vote share between 1930 and 1933, when political news had an anti-Nazi slant. This negative effect was fully undone in just one month after Nazis got control over the radio in 1933 and initiated heavy radio propaganda. Radio also helped the Nazis to enroll new party members and encouraged denunciations of Jews and other open expressions of anti-Semitism after Nazis fully consolidated power. Nazi radio propaganda was most effective when combined with other propaganda tools, such as Hitler’s speeches, and when the message was more aligned with listeners’ prior as measured by historical anti-Semitism.

There are several nice features that these papers have in common. The first is spatially disaggregated data, allowing for more fine-grain analysis of variation over space. (Although as a commenter at one ISA panel pointed out, this is not necessarily useful for all research questions.) Another feature I like is that both go to great lengths to test the robustness of their findings–this is a positive development for the field and I hope the trend continues.

See also: Thomas Zeitzoff sends along two more papers on the topic: “Opium for the Masses: How Foreign Media Can Stabilize Authoritarian Regimes” (Kern and Hainmueller, 2009) and “Propaganda and Conflict: Theory and Evidence from the Rwandan Genocide” (Yanagizawa-Drott, 2012).


*Note: Jan got his PhD at Duke and Florian is currently in the program. Both are friends of mine.

Kurds and Statelessness

Kurdish peshmerga--literally "those who face death"--standing guard at Shenarwe Mountain

Kurdish peshmerga–literally “those who face death”–standing guard at Shenarwe Mountain

Last week one of my academic heroes, James C. Scott, came to Duke to give two talks. The first was a lunchtime discussion of his recent book, Two Cheers for Anarchism. The second was a lecture elaborating on The Art of Not Being Governed. We have discussed the argument of the latter book here before. To oversimplify quite a bit, Scott says that the upland peoples of Southeast Asia consciously evaded the intrusion of lowland governments into their lives.

Scott recognizes that his argument applies outside of Asia as well, but does not delve into specifics. My favorite example of this is the Kurdish people, who are located in the mountainous region of northern Iraq, southern Turkey, northeastern Syria, and northwestern Iran. As Scott would say, they are at the periphery of several states and the center of none. It is also an increasingly strategic region, and Kurds find themselves in a position to shape the balance of power:

After decades of persecution and genocide, the Kurds have found a way to operate in a neighborhood where clear-cut borders can often be more of a nuisance than a boon. Loosely promised a state by the 1920 Treaty of Sèvres, the Kurdish people have learned the hard way that maps don’t necessarily dictate facts on the ground, as any observer of Mideast history and politics can attest. “Though the Kurds are said to be the world’s largest stateless people,” writes Time contributor Pelin Turgut, “Kurdish leaders … say they are no longer interested in a single Kurdish state but in a loose federation that spans various national borders.” Rather than waiting for Mideast leaders or the international community to make a deal for a state, the Kurds seem to be playing a regional game of “Let’s Make A Deal.”

With the recent call for a ceasefire by PKK leader Abdullah Ocalan, Kurdish-Turkish relations appear to be improving. This is an important transition since until now Kurdish leaders have been closer to Baghdad than Ankara. Bashar al-Assad has recently increased Kurdish autonomy as he seeks their support in Syria’s civil war. To take an optimistic view, this stateless people may soon find themselves playing kingmaker in the region.

See also: The Kurdish Factor” by Matthieu Akins