Weekend links

1) Anesthesiologist Fabricates 172 Papers (via Michael Clemens)

2) This much I know: Daniel Kahneman (via MR)

3) Tatyana Deryugina's new paper on local weather fluctuations and attitudes towards climate change (also via MR)

4) A Visual Git Reference

5) Version 3.0 of the Social Conflict in Africa Database (SCAD) is out (via Mona Khalidi)

6) Number sense across the lifespan as revealed by a massive Internet-based sample (PNAS, via Kyle Meng)

7) Development economics and my native borough (via Dave Pell)

8) Optimal TED Talk Structure

9) The IDV User Experience blog has some great (mostly spatial) data visualizations (via Reed Walker)


10) Graphing Every (Wikipedia) Idea in History

11) Convection over Manhattan this past Wednesday

Less is more

There are many things we can do to make our research clearer to readers: make our text well organized and accessible, make clear graphs, consider the psychology of our readers, and use as little math as is necessary to explain our point.  Clarity and elegance trumps formalism and detail.


Intimidated by Equations?
Barbara R. Jasny

Although there is general agreement on the value of a strong tie between theory and data, forging links between theoretical and empirical approaches (and practitioners) is not as straightforward as it should be. New evidence of this disconnect comes from the work of Fawcett and Higginson, who examined the use of mathematical equations in 649 papers dealing with ecology and evolution that were published in 1998. They gathered citation data, excluding instances of self-citation. An increase in the number of equations per page of main text corresponded to a lower rate of citations. Overall, each additional equation in the main text of a paper was associated with a 28% decrease in the citation rate. Burying the equations in an appendix had a salutary effect on citation rate. When the citing papers were divided into theoretical and nontheoretical on the basis of their use of the word "model" in the abstract or title, the authors observed that the negative effect was due to the nontheoretical papers not citing papers with equations. There are caveats to the conclusions—examinations over longer periods of time, analysis of the relative content of the papers, and examination of the effect for online rather than print publication are all warranted. Although the authors conclude that better math education for biologists is the best long-term solution, they suggest that more immediate strategies could include the addition of explanatory text between equations.

The full PNAS article is here.

h/t Marshall Burke

Does climate affect conflict? Evidence from Shakespeare

Mark Cane sends us this:

ROMEO and JULIET         ACT 3, SCENE 1a 

[A street. MERCUTIO, BENVOLIO & Servants] 

BENVOLIO
I pray thee, good Mercutio, let's retire.
The day is hot, the Capulets abroad,
And if we meet we shall not 'scape a brawl,
For now these hot days is the mad blood stirring.

[And later they do meet the Capulets and Tybalt kills Mercutio, then Romeo kills Tybalt and the rest is tragedy.]

For more fun evidence on the psychological effect of heat on aggression, see evidence from road rage and MLB.  Also this.

Using cell phones to track post-disaster population movements in Haiti

Predictability of population displacement after the 2010 Haiti earthquake

Xin Lu, Linus Bengtsson, and Petter Holme

Abstract: Most severe disasters cause large population movements. These movements make it difficult for relief organizations to efficiently reach people in need. Understanding and predicting the locations of affected people during disasters is key to effective humanitarian relief operations and to long-term societal reconstruction. We collaborated with the largest mobile phone operator in Haiti (Digicel) and analyzed the movements of 1.9 million mobile phone users during the period from 42 d before, to 341 d after the devastating Haiti earthquake of January 12, 2010. Nineteen days after the earthquake, population movements had caused the population of the capital Port-au-Prince to decrease by an estimated 23%. Both the travel distances and size of people’s movement trajectories grew after the earthquake. These findings, in combination with the disorder that was present after the disaster, suggest that people’s movements would have become less predictable. Instead, the predictability of people’s trajectories remained high and even increased slightly during the three-month period after the earthquake. Moreover, the destinations of people who left the capital during the first three weeks after the earthquake was highly correlated with their mobility patterns during normal times, and specifically with the locations in which people had significant social bonds. For the people who left Port-au-Prince, the duration of their stay outside the city, as well as the time for their return, all followed a skewed, fat-tailed distribution. The findings suggest that population movements during disasters may be significantly more predictable than previously thought.

h/t Kyle

Early images of earth from space

Everyone knows the famous images of earth rise taken from the moon, but I surprised to run across this earlier amazing 1955 image from space. They pieced it together from a bunch of snapshots automatically shot though a pinhole in the side of a rocket as it rotated at its apex and fell back to earth.

Click to enlarge and read description.

Also cool is this first TV image from the space.

For a sense of our progress in extraterrestrial photography, compare these with the incredibly high-res images from the Suomi satellite released earlier this year.

The “Soft Side” Approach to Countering Violent Extremism

This is a guest post by Daniel P. Aldrich, associate professor of public policy at Purdue University. Prof. Aldrich was an American Association for the Advancement of Science (AAAS) fellow at USAID during the 2011-2012 academic year, and a Fulbright research fellow at the University of Tokyo during the 2012-2013 academic year.  He can be reached at daniel.aldrich@gmail.com, and followed at @DanielPAldrich on Twitter.


Violent extremism and terrorism - involving suicide bombings, improvised explosive device and small arms attacks, narco-trafficking, and kidnapping - have taken center stage for many decision makers in the United States and abroad.  The Worldwide Incidents Tracking System (WITS) established by the National Counterterrorism Center has illuminated a rising trend in the number of armed attacks by terror groups over the past decade.  Scholars (using synthetic case control analysis from Spain) have estimated the high economic costs of terrorism, with a loss of 10% in per capita GDP for individuals in areas with high numbers of terrorist attacks (Abadie and Gardeazabal 2003). Policy makers around the world have prioritized their attempts to end, manage, or handle threats from violent extremist organizations (VEOs) such as al-Qaeda in the Islamic Maghreb (AQIM) in northwest Africa, Lashkar-e-Tayyiba in South Asia, and Abu Sayyaf in the Philippines.


Given the broad agreement that violent extremism is a serious issue, what are the best policy responses to violent extremist organizations?  U.S. policymakers have long favored the use of military force, drone strikes, and covert operations as tried-and-true approaches for dealing with extremist groups because they produce clear and immediate results.  These tactics bring with them unintended side effects.  Even the most advanced unmanned drones using the latest in surveillance and tracking technologies have generated civilian casualties and turned host nations partners against the United States.  Such “collateral damage” further drives many local residents to support anti-American groups and bolsters their claims of encirclement and anti-Muslim bias.  National governments and local civilian populations in Pakistan and Yemen provide two unfortunate examples of this phenomenon.
[continued after the break]

Weekend Links

1) On giving (bad) advice to kings (via bb)

2) The epidemiological transition as illustrated by cause of death (NEJM, also via bb)

3) The Cost of Friendship (NBER via, *cough cough*, Sol)

4) A popular press indictment of hurricane risk modeling

5) Estimating the welfare loss of natural disasters in developing countries using willingness to contribute labor (via Amir)

6) Visualizing an infection in real time (via Ram)

7) The New Yorker's top five TED talks (via Dave Pell)

8) Design and Analysis of a Text Mining Experiment (via Suresh)

9) Skill Premia in Commercialized Sex Markets

10) Michael Lewis on idiosyncratic human capital outcomes and public good provision (basically)

Neurological basis for altruism

I don't usually read Nature Neuroscience, but this is an interesting neuro-economics piece.

Dorsolateral and ventromedial prefrontal cortex orchestrate normative choice

Thomas Baumgartner, Daria Knoch, Philine Hotz, Christoph Eisenegger & Ernst Fehr

Abstract: Humans are noted for their capacity to over-ride self-interest in favor of normatively valued goals. We examined the neural circuitry that is causally involved in normative, fairness-related decisions by generating a temporarily diminished capacity for costly normative behavior, a 'deviant' case, through non-invasive brain stimulation (repetitive transcranial magnetic stimulation) and compared normal subjects' functional magnetic resonance imaging signals with those of the deviant subjects. When fairness and economic self-interest were in conflict, normal subjects (who make costly normative decisions at a much higher frequency) displayed significantly higher activity in, and connectivity between, the right dorsolateral prefrontal cortex (DLPFC) and the posterior ventromedial prefrontal cortex (pVMPFC). In contrast, when there was no conflict between fairness and economic self-interest, both types of subjects displayed identical neural patterns and behaved identically. These findings suggest that a parsimonious prefrontal network, the activation of right DLPFC and pVMPFC, and the connectivity between them, facilitates subjects' willingness to incur the cost of normative decisions.

(a) Overlay of the pVMPFC cluster that showed a larger change in connectivity after unfair offers (compared with fair offers) with the right DLPFC in the left compared with the right TMS group (yellow, at P < 0.005, cluster extent = 18 voxels42) and the pVMPFC cluster that showed differential activation in the contrast unfair > fair offers in the left compared with the right TMS group (red). Overlapping voxels are displayed in orange. (b) Bar plots based on the functional ROI (red) from a indicate that the differential context-dependent change in connectivity between the left and right TMS group was qualified by a differential change in connectivity during unfair offers (unfair connectivity), but not during fair offers (fair connectivity). The left TMS group therefore only showed an increased connectivity between the right DLPFC and pVMPFC at P < 0.01 during unfair offers, whereas the connectivity between these two brain regions did not change (relative to baseline connectivity) after fair offers. Moreover, after right TMS, the connectivity between right DLPFC and pVMPFC never deviated from the baseline (indicated by the two black bars); that is, these brain regions no longer communicated more after unfair offers. Bar plots depict mean ± s.e.m. [From Nature Neuroscience]

Climate and the [historical] slave trade

This is an interesting data set and a neat reduced-form result, although I think the mechanism is less clear than the authors suggest. I also like that the authors are drawing from a wider body of literature than is usual (and from their references, I can't but help get the creeping feeling that they might be reading FE).

Climate, ecosystem resilience and the slave trade

James Fenske and Namrata Kala

African societies exported more slaves in colder years. Lower temperatures reduced mortality and raised agricultural yields, lowering the cost of supplying slaves. Our results help explain African participation in the slave trade, which is associated with adverse outcomes today. We merge annual data on African temperatures with a panel of port-level slave exports to show that a typical port exported fewer slaves in a year when the local temperature was warmer than normal. This result is strongest where African ecosystems are least resilient to climate change, and is robust to several alternative specifications and robustness checks. We support our interpretation using evidence from the histories of Whydah, Benguela, and Mozambique.

h/t Ted Miguel

Weekend links

1) Ironspread: Scripting Excel using Python

2) Is Chagas Disease the "New HIV/AIDS of the Americas"? (PLoS Neglected Tropical Diseases)

3) Geography, land quality, and the origins of ethnolinguistic diversity (AER)

4) Per capita income correlates with tree density (via bb)

5) Defensive patent licensing pools

6) Humans may have only been partly responsible for the loss of wooly mammoths (Nature)

7) Dani Rodrik on the future of the nation state

8) Germany vs. the Euro area in 7 easy graphs (via cp)

9) "The safe release of genetically-modified [malaria-resistant mosquitos] into the wild will be an issue down the line..." (PNAS)

10) Creating the new development ecosystem (Science, via Hannah)

11) Daniel Aldrich's exhaustive lit review on the politics of natural disasters (via Amir)

12) An economic history of the Sinaloa Cartel (via Dave Pell)

Diarrhoea in Bangladesh: displaying results from fixed effects models

I ran into this 2008 paper doing hurricane work with Jesse. The results are not extremely surprising, but I really liked how they displayed their result.  Many of us use high-dimensional data and multiple regression models to try and account for the many different processes that occur in social data, but it is often difficult to clearly display the effect of just one process while also being clear about all the other controls in the model. I like the approach of this team: they show predictions form the complex model (eg. with week and month fixed effects, socioeconomic controls, etc.) overlaid with the real data.


Factors determining vulnerability to diarrhoea during and after severe floods in Bangladesh
Masahiro Hashizume, Yukiko Wagatsuma, Abu S. G. Faruque, Taiichi Hayashi, Paul R. Hunter, Ben Armstrong and David A. Sack

Abstract: This paper identifies groups vulnerable to the effect of flooding on hospital visits due to diarrhoea during and after a flood event in 1998 in Dhaka, Bangladesh. The number of observed cases of cholera and non-cholera diarrhoea per week was compared to expected normal numbers during the flood and post-flood periods, obtained as the season-specific average over the two preceding and subsequent years using Poisson generalised linear models. The expected number of diarrhoea cases was estimated in separate models for each category of potential modifying factors: sex, age, socio-economic status and hygiene and sanitation practices. During the flood, the number of cholera and non-cholera diarrhoea cases was almost six and two times higher than expected, respectively. In the post-flood period, the risk of non-cholera diarrhoea was significantly higher for those with lower educational level, living in a household with a non- concrete roof, drinking tube-well water (vs. tap water), using a distant water source and unsanitary toilets. The risk for cholera was significantly higher for those drinking tube-well water and those using unsanitary toilets. This study confirms that low socio-economic groups and poor hygiene and sanitation groups were most vulnerable to flood-related diarrhoea.

Only the finest in Swiss data visualiation

The data visualization specialists over at Chart Porn point us to Datavisualization.ch's Selected Tools page. From their blog post announcing it:

When I meet with people and talk about our work, I get asked a lot what technology we use to create interactive and dynamic data visualizations. [...] That’s why we have put together a selection of tools that we use the most and that we enjoy working with. We called it selection.datavisualization.ch. It includes libraries for plotting data on maps, frameworks for creating charts, graphs and diagrams and tools to simplify the handling of data. Even if you’re not into programming, you’ll find applications that can be used without writing one single line of code. We will keep this list as a living repository and add / remove things as technology develops. We hope this will help you find the best tool for your next job.

Guess it's time to learn a little javascript...

Why we aren't so great at "climate management"

I ran into this today:

This Global Map of Science is based on research-front data for the six-year period ending in December 2009. The map shows the major subject areas within fields linked together in a network based on the same principles as our research-front maps showing highly cited papers. To create a map of science, we start with all research fronts in Essential Science IndicatorsSM from Thomson Reuters, and compute the links between fronts based on how often they are co-cited—that is, the frequency that current papers jointly cite two given fronts. Successive applications of a clustering process then groups fronts into larger aggregates. Each circle on the map represents a cluster or aggregate of research fronts on a broad topic within that field. Annotations have been added to this map which represent the main research themes. These appear as labels attached to specific regions on the maps. Additional information about Research Fronts.

Us interdisciplinary folks have something to learn from the hepatitisologists...

Elinor Ostrom on cities and sustainability

Elinor Ostrom passed away this week, and in doing so deprives the world of one its great political economists. To wit: this thought provoking op-ed, published post-humously, on the role of decentralized policy making in sustainability:

Much is riding on the United Nations Rio+20 summit. Many are billing it as Plan A for Planet Earth and want leaders bound to a single international agreement to protect our life-support system and prevent a global humanitarian crisis. 

Inaction in Rio would be disastrous, but a single international agreement would be a grave mistake. We cannot rely on singular global policies to solve the problem of managing our common resources: the oceans, atmosphere, forests, waterways, and rich diversity of life that combine to create the right conditions for life, including seven billion humans, to thrive.  

We have never had to deal with problems of the scale facing today’s globally interconnected society. No one knows for sure what will work, so it is important to build a system that can evolve and adapt rapidly. 

Decades of research demonstrate that a variety of overlapping policies at city, subnational, national, and international levels is more likely to succeed than are single, overarching binding agreements. Such an evolutionary approach to policy provides essential safety nets should one or more policies fail.

Emphasis is my own. The rest is worthwhile.

Another reason to love/hate elections

While reading about different reasons why climate might influence conflict, I ran into this interesting find from PNAS 2010:

Irrelevant events affect voters’ evaluations of government performance
Andrew J. Healy, Neil Malhotrab, and Cecilia Hyunjung Mo

Abstract: Does information irrelevant to government performance affect voting behavior? If so, how does this help us understand the mechanisms underlying voters’ retrospective assessments of candidates’ performance in office? To precisely test for the effects of irrel- evant information, we explore the electoral impact of local college football games just before an election, irrelevant events that government has nothing to do with and for which no government response would be expected. We find that a win in the 10 d before Election Day causes the incumbent to receive an additional 1.61 percentage points of the vote in Senate, gubernatorial, and presidential elections, with the effect being larger for teams with stronger fan support. In addition to conducting placebo tests based on postelection games, we demonstrate these effects by using the betting market’s estimate of a team’s probability of winning the game before it occurs to isolate the surprise component of game outcomes. We corroborate these aggregate-level results with a survey that we conducted during the 2009 NCAA men’s college basketball tournament, where we find that surprising wins and losses affect presidential approval. An experiment embedded within the survey also indicates that personal well-being may influence voting decisions on a subconscious level. We find that making people more aware of the reasons for their current state of mind reduces the effect that irrelevant events have on their opinions. These findings underscore the subtle power of irrelevant events in shaping important real-world decisions and suggest ways in which decision making can be improved.

Reminds me of this one on beliefs regarding global warming, and this one on whether to go to college.

Nature on Rio+20

Johannes points out that Nature is running a special issue on the environment in honor of Rio +20. Of special interest is the following by Barnosky et al.:

Approaching a state shift in Earth’s biosphere 

Localized ecological systems are known to shift abruptly and irreversibly from one state to another when they are forced across critical thresholds. Here we review evidence that the global ecosystem as a whole can react in the same way and is approaching a planetary-scale critical transition as a result of human influence. The plausibility of a planetary-scale ‘tipping point’ highlights the need to improve biological forecasting by detecting early warning signs of critical transitions on global as well as local scales, and by detecting feedbacks that promote such transitions. It is also necessary to address root causes of how humans are forcing biological changes.

There's a nice discussion article over at the NY Times' Green blog:

In interviews, scientists involved in writing the paper acknowledged that the 50 percent threshold was simply a best guess, based on extrapolating the earlier research. But they said they were deeply concerned about many of the trends on the planet and the seeming inability of the world’s political leadership to grapple with them. 

The situation “scares the hell out of me,” said one author of the paper, James H. Brown, who is a macroecologist at the University of New Mexico and a member of the National Academy of Sciences. “We’ve created this enormous bubble of population and economy. If you try to get the good data and do the arithmetic, it’s just unsustainable. It’s either got to be deflated gently, or it’s going to burst.”

These sorts of articles come out sufficiently frequently that I think we may need to call in some science historians to do a lit review of eschatology in ecology...

Weekend Links

1) Routes and imputed travel times between 751 sites in ancient Rome (via The Economist)

2) AfricaMap: a collaborative GIS data project at Harvard (via Hannah)

3) OpenROV, a $750 open source submarine Will someone at one of the oceanographic institutes get a grant together to swarm these, please?

4) The gap in US black-white life expectancy appears to be shrinking (via Will)

5) Why Do Firms Use Non-Linear Incentive Schemes? (or "understanding sales jobs")

6) The UN Global Pulse Report on Big Data for Development, and commentary by Patrick Meier (via Emmanuel)

7) On switching from Stata to R (via Johannes)

8) “If you want to live longer and healthier than the average American, come to New York City” (The Lancet, via Krista)

9) Multiple Event Studies in Public Finance: ASimulation Study with Applications

10) "I need the rest of you to help me fix the world." A round up of this year's best commencement addresses (via Dave Pell)

11) Why I'm leery of field research

Climate Change and Sustainable Development: Key Contributions Since May 2011

[This is the last in a four-part series of guest posts by first year students in Columbia's Sustainable Development program]

Climate Change and Sustainable Development: Key Contributions Since May 2011

By: Meg Sutton, Matthias Pfaff, and Anthony Louis D'Agostino

This past March, the US registered the warmest average March temperature on record, while more than 15,000 warm temperature records were broken.  Far from an anomaly, global temperature records over the last two decades have been marching upward with "nine of the ten warmest years [occurring] in the 21st century."

Rising temperature trends, alongside other anticipated effects of climate change, will pose formidable challenges to development.  To be effective, policy responses require the most current and reliable science available.  Since this knowledge is continually evolving, we reviewed research published over the last year on the link between climate change and sustainable development, and have composed this summary of what we think will become key papers on this topic.  

Butting Heads: A Year’s Review of Research in the Context of the Global Energy Paradox

[This is the third in a four-part series of guest posts by first year students in Columbia's Sustainable Development program]

Butting Heads: A Year’s Review of Research in the Context of the Global Energy Paradox

By: Aaron Baum, Pablo Egaña and Erin McNally.

Today, the energy sector emits around two-thirds of global greenhouse gas emissions; yet, around one-quarter of the world's population has basic energy needs that are not being met and are rising.  There is a paradox in the pursuit of the dual goal to curb emissions by meeting demand via technology, which was impressively discerned by William S. Jevons more than a hundred years ago: technological progress that achieves higher levels of efficiency and decreased negative environmental effects tends to be accompanied by a decrease in the price of the resource, with a consequent increase in consumption rates.  Jevons’s paradox obliges us to scrutinize the view that the dual problem of rising emissions and demand can be simply resolved through the increased efficiency that technological progress yields.

In what direction is the research into viability – in terms of costs and feasibility – of carbon capture as well as generation and storage of sustainable energy headed?  In the following, we briefly explore answers to this question from selected investigations in leading scientific journals (Nature, Science and PNAS), focusing on the role that technology can play in sustainable development and the role of natural disasters in investment.

The Global Food System and Water Crisis: 10 Science Papers from the Past Year

[This is the second in a four-part series of guest posts by first year students in Columbia's Sustainable Development program]

The Global Food System and Water Crisis: 10 Science Papers from the Past Year

By StephanieLackner, Xiaojie Zhang, Kayleigh Campbell

To get caught up on the latest research on the global food system and water crisis we did a survey of the must-read articles from the last twelve months.  The requirements to make our list were simple.  First, the article had to be from the Research Articles or Reports sections of Science or the Review, Articles, or Letters sections of Nature published between May 2011 and April 2012.  Then we picked the ones that we thought would have the most significant impact on humans, were the most immediate or critical concerns, or were the most unique solutions to the current crises faced.  And here they are…