Church or Beer? Americans on Twitter

In honor of the anniversary when American colonists kicked out the oppressive British (apologies to Mark and other oppressive Brits) today is the birthday of the United States. Traditionally it is celebrated by attempting to blow up or burn a small part of it with fireworks, and given the dry conditions at the moment, we may very well succeed at this beyond our wildest expectations.

But until #badideaswithfireworks becomes a trending hash tag, we thought we'd use Twitter to explore some of the regional differences that are rending the fabric of society make America great. It also gives us a chance to showcase some of the potential of our nascent DOLLY project (feel free to visit the Knight News Challenge website and comment positively!), which integrates and maps geographic social media and official data sources. DOLLY is still not quite ready for general use, but the backend database is all set which makes it really easy to pull out user generated geocoded data, in this case from Twitter.

So in honor of the 4th of July, we selected all geotagged tweets^[1] sent within the continental US between June 22 and June 28 (about 10 million in total) and extracted all tweets containing the word "church" (17,686 tweets of which half originated on Sunday) or "beer" (14,405 tweets which are much more evenly distributed  throughout the week). See below for more technical details^[2] or just go straight to the map below to see the relative distribution of the tweets in the U.S.

Relative Number of Tweets containing the terms "church" or "beer" aggregated to the county level, June 22-28, 2012

This map clearly illustrates some fairly big regional divides (more on that in a bit) but it is worth drilling down a bit to see how this plays out at the local level.  San Francisco has the largest margin in favor of "beer" tweets (191 compared to 46 for "church") with Boston (Suffolk county) running a close second. Los Angeles has the distinction of containing the most tweets overall (busy, busy thumbs in Southern California). In contrast, Dallas, Texas wins the FloatingSheep award for most geotagged tweets about "church" with 178 compared to only 83 about "beer."

Of course, since these are tweets, the content is decidedly less spiritual than one might expect given the focus on beer and church.  For example, the most common example of a "church" tweet was simply a report such as "I am at _______ church".  More amusing are what we characterize as "competitive church going" when one person replaces another as the Foursquare "mayor" of a church. "I just ousted Jef N. as the mayor of Dallas Bible Church on @foursquare! 4sq.com/5hNW6x" 

This of course echoes the Sermon on the Mount and the famous verse, "Blessed are those who check in for they shall inherit the badges of righteousness."  Another common category were politically related tweets such as "#ICantDateYou If You Dont Go To Church" or "@____ you're right. It's like separation of church and state. But they really shouldn't be separated. #twitterpolitics". 

Given the cultural content of the "church" tweets, the clustering of relatively more "church" than "beer" content in the southeast relative to the north-east suggests that this could be a good way to identify the contours of regional difference. In order to quantify these splits, we ran a Moran's I test for spatial auto-correlation which proved to be highly significant as well.^[3] Without going into too much detail, this test shows which counties with high numbers of church tweets are surrounded by counties with similar patterns (marked in red) and which counties with many beer tweets are surrounded by like-tweeting counties (marked in blue).  Intriguingly there is a clear regional (largely north-south split) in tweeting topics which highlights the enduring nature of local cultural practices even when using the latest technologies for communication.

We also note that this map strongly aligns with the famous 'red state'/'blue state' map from the 2000, 2004, and 2008 elections with a strong "religious right" component in the Southeastern United States (see also The Virtual 'Bible Belt') and a more liberal, or at least beer-tweeting, Northeast and upper Midwest (see also The Beer Belly of America).

In any case, happy 4th of July to our American readership. We hope you enjoy your beer in the north, or your church service if you are tweeting from the south.

----------------------
[1] It is important to note that geotagged tweets are somewhat of an oddity among tweets, as only one to three percent of tweets (depending on the country) are geotagged.  Still a small percentage of a very large number (the total number of tweets) results in a LOT of data.
 
[2] There are a number of technical issues tied to the validity and scale of geography associated with tweets which we won't go into here but it is worth mentioning that we are NOT using user profile locations.  This data is limited to geographic information associated with each tweet, often drawn from a GPS capable device.  While the relevant scale at which analysis can be done differs between tweets about 90 percent of the tweets in this sample are accurate on the city level or lower which works well for this analysis.
 
[3] Based on  IDW matrix for 2.34 decimal degrees (Euclidean distance), this test achieved a z-score of 14.34, implying there is a less than 1% likelihood that this high-clustered pattern could be the result of random chance.

What do church, bowling, firearms and strip clubs have in common?

One answer (or at least the one we're willing to print) is that they all represent ways in which Americans can spend their time. But which parts of North America are more focused on one or the other? Or, more precisely, where are the resources for each activity more available? Using the number of listings indexed by the Google Maps directory[1], the map below visualizes the comparative prevalence of churches, bowling alleys, guns and strip clubs across the US (as well as parts of Canada and Mexico). Each point is color coded according to which activity had the most number of hits in the Google Maps directory.

Upon first glance, it is easy to see the relative supremacy of two topics, churches (in blue) and guns (in green), which cover most of the points in North America. Churches dominate throughout most of the southeast and upper midwest (echoing our findings from the virtual bible belt map) while the Northeast, the West and much of Canada show a higher number of listings for guns. One should not, however, interpret this to mean that guns are more prevalent in Canada than the southern U.S. (which clearly does not equate with the offline reality). Instead, the Northeast and Canada have relatively fewer listings for churches than in the south, leading them to be color coded with the next leading activity, i.e., guns. Likewise, there are plenty of gun listings in the southeastern United States, they are simply overshadowed by the listings for churches.

Of more interest are the small pockets in which either bowling alleys or strip clubs are most numerous, bucking the near-universal trend focused on guns and church. For example, there is a prevalence of strip clubs around Las Vegas and Reno, Nevada, as well as Los Angeles, California. Additionally, Canadian cities seem particularly well represented with clusters in Montreal, the Buffalo-Toronto corridor and the Seattle-Vancouver region. Interestingly enough, there seems to be some correspondence (especially in the Northwest US and Toronto) with our map outlining user-generated definitions of fun.

The small pockets of strip clubs around eastern Tennessee along the North Carolina and Georgia borders seem inexplicable, until one considers the advertising landscape along the I-75 corridor, in which religious and pornographic iconography are ubiquitously juxtaposed.

The few areas in which the bowling alleys outnumber churches, guns and strip clubs, are more difficult to explain. There seems to be little rhyme or reason for these bowling hot spots, as they do not correspond well with places with a relative specialization in bowling alleys. The areas shown in red are exclusively rural, so their classification may simply be a result of there not being much else there. Or their residents could really like their bowling. In any case, we plan on contacting Robert Putnam and seeing if he can offer any insight on this.


[1] Google Maps directories are drawn from a range of sources such as yellow page listings. This category is distinct from and excludes user-generated placemarks used in other maps found on Floatingsheep.

Baptists, bibliophiles, and bibles, Oh My!

Two powerful and often opposing forces within society are faith and reason. Regardless of the extent to which a cultural war exists, the balance between the two (e.g., teaching evolution in the schools, etc.) is a prominent feature of popular socio-political discourse in the United States. Thus, the topics makes a perfect subject of a map and leads us to ask which parts of the country prefer bookstores to bibles? What's the ratio of Baptists to bibliophiles?
Using the number of Google Maps directory listings[1] for "bookstores" and "churches" as proxy values, this visualization maps the spectrum of the faith and reason conflict. As there are an overwhelmingly larger number of churches than bookstores nationwide it is important to index each of these variables before comparison. The technique used in this map was to divide the number of churches (or bookstores) at a location by the national average of churches or bookstores. If a location had twice the number of churches as the national average it would receive an indexed value of 2. Similarly having only 50 percent of the national average of bookstores would produce an indexed value of 0.5. The church index was then divided by the bookstore index to see each locations relative balance of churches to bookstores. If each of the indexed values were the same, the faith-reason index would be equal to 1. But as in the case of the example above (church index = 2, bookstore index = 0.5) the faith-reason index would be 4. This indicates that this particular location has a much higher relative number of churches to bookstores. In order to exclude places that had approximately equal number of churches and bookstores, this map only includes locations where the faith-reason index was skewed more than 20 percent in either direction (i.e., values greater than 1.2).

For the most part, the relative prevalence of bookstores occurs in and around the big cities - Los Angeles, California is the site of the highest indexed value, and is joined by the megalopolis of the eastern seaboard as having the highest concentrations in favor of bookstores. Even cities such as Atlanta, nestled in the Bible Belt of the American southeast, tend towards a relatively large number of bookstores. On the converse, other large cities like Dallas, San Antonio and Houston continue to favor churches, with New Orleans (the largest city in Louisiana) having the highest relative concentration of churches in the nation. Suburban areas surrounding large population centers also show a near-universal favoritism for churches.

So while there appears to be no single variable determining the local trends toward faith or reason, it is evident that even some of the most common assumptions regarding the geographies of faith and reason have proven to be more complicated; not all large cities are necessarily bookish, but neither is the bible belt a homogeneous geographic unit.

[1] Google Maps directories are drawn from a range of sources such as yellow page listings. This category is distinct from and excludes user generated placemarks that we use in other maps.

The Virtual ‘Bible Belt’

The size of the dots in this map represents the relative number of mentions of the word “church” in placemarks uploaded to Google. Results for the word “church” have been divided by the "0" and "1" baseline measure (see the last two blog posts), thus highlighting the parts of North America in which mentions of the word “church” are over- and under- represented. Interestingly, while the “bible belt” in the physical world is often talked about as being synonymous with the American South, the virtual “bible-belt” additionally incorporates large parts of the Midwest. Less surprising is the fact that the Northeast and the West have relatively low scores. The GeoWeb is in many ways a mirror (albeit a distorted one) of the physical places that it represents.