Google search data for forensic epidemiology

Two recent papers have come out demonstrating that Google searches can provide extraordinarily rich data for forensic epidemiologists:

Declining public interest in the drought

David Lobell mentioned that there seemed to be less news coverage of the drought, so I checked Google Trends and David was right. Looking just the USA, interest in the drought peaked about a week ago:

(news report volume looks similar, but Google doesn't give me the raw data). Is interest/news falling because the nation's corn crop has recovered? Probably not.  But a week ago, something else took over the airwaves and peoples' attention:

Is this spurious? It's possible, but this general pattern is well documented. In a 2007 article, David Strömberg linked the quantity of US disaster relief (a proxy for public interest) to "whether the disaster occurs at the same time as other newsworthy events, such as the Olympic Games, which are obviously unrelated to need."  He concludes "that the only plausible explanation of this is that relief decisions are driven by news coverage of disasters and that the other newsworthy material crowds out this news coverage." So it isn't crazy to think that the London Games might soak up some of the public interest that would otherwise go towards our own drought.

In a closely related 2011 paper, Matthew Kahn and Matthew Kotchen showed that "an increase in a state's unemployment rate decreases Google searches for "global warming" and increases searches for "unemployment."" 

Yet, while it seems unlucky for folks in the midwest to get hit by this drought during the Olympics, they are "lucky enough" to get hit just before the presidential race. In their 2007 paper, Thomas Garrett and Russell Sobel "find that presidential and congressional influences affect the rate of disaster declaration and the allocation of FEMA disaster expenditures across states. States politically important to the president have a higher rate of disaster declaration by the president... Election year impacts are also found. Our models predict that nearly half of all disaster relief is motivated politically rather than by need. The findings reject a purely altruistic model of FEMA assistance and question the relative effectiveness of government versus private disaster relief."

(cross posted on G-FEED)

Google Correlate

Google Correlate goes live at Google Labs today. It provides correlative search by time or US state and returns the top most-correlated search terms and / or data series. For particularly Fight Entropy-ish content, check out terms that correlate with:

• state level annual rainfall
• Kyoto Protocol
• hurricane
• record high temperature (note the top hit)
• El Nino Southern Oscillation (Sol will like this one)

Also: their explanatory webcomic manages the rare feat of being simultaneously cute and informative.

Stata's new geocode function

Our friend and colleague Reed Walker points out that there's a new Stata program called geocode that allows an internet-connected copy of Stata to query Google Maps for latitude and longitude. From Adam Ozimek at the excellent econ and general social science blog Modeled Behavior :

In the upcoming Stata Journal I have a paper with a coauthor that lets Stata query Google Maps in order to find latitude and longitude for addresses or other locations, also known as geocoding. What makes this useful is that you can have weird formatting, spelling errors, or missing information in your address or location variable and the program can still geocode it as well as Google Maps can place it on a map.

There's another program that calculates the "Google maps distance" (i.e., actual travel time distance as opposed to as-the-crow-flies geometric distance) between any two addresses. More details can be found here. This is very exciting.