The only way to introduce this post is to say that yes, a bunch of really naive and/or, in the case of the local television news media, willfully idiotic, people thought that there was going to be a 'purge' -- a 12 hour period where all crime is made legal -- in Louisville, Kentucky on the night of Friday, August 15th, 2014. Starting with a single tweet from a local high school student, things quickly grew out of control, with #LouisvillePurge becoming a trending topic nationally by the time things were all said and done. While the best tweets referencing the purge made light of the phenomena, there were many, many more expressing confusion, fear, bewilderment and a desire to save the poor souls who might have been convinced to participate in such an event. But for all the attention given to the role of social media in spreading the hysteria , there's been no attempt to look at the where some of these tweets were coming from, and how the news spread over space and time.
While the tweet that kicked the whole ordeal off was created at 8:32pm on Sunday, August 10th, the first geotagged tweet with the #LouisvillePurge hashtag didn't show up for another couple of days, at 11:33pm on Wednesday, August 13th. Beginning with that tweet, we collected all geotagged tweets with the hashtag through noon on Saturday, August 16th, at which point things were dying down.
The map below shows the overall distribution of these 4,351 geotagged tweets, aggregated to hexagonal cells across the continental United States. While Louisville and the surrounding areas clearly have the highest concentrations, the discussion of the Louisville Purge was truly trans-local, with less than 25% of the total number of geotagged tweets coming from the Louisville Metro area. Of areas further away from Louisville in absolute distance, Houston, Dallas and Los Angeles represent some of the highest concentrations of tweeting about the (non-)event.
All #LouisvillePurge Tweets thru August 16th at 12pm EDT
But perhaps more interesting than just the overall spatial distribution is how this distribution evolved over time, from the first geotagged tweet all the way through the cycle of hype and hysteria that led the Louisville Purge to be featured on any number of national news websites. In the series of maps below, we have divided all of the tweets in our dataset into a series of (more-or-less arbitrary) time frames that give a good idea of when and where the news spread to other parts of the country .
The lead up to the purge demonstrates a relatively localized phenomenon within Louisville, though it's interesting that there is some extra-local tweeting from the very beginning, with a very small number of tweets coming from outside the state in West Virginia, Kansas, Texas and Florida. There were only a total of 182 geotagged tweets referencing #LouisvillePurge in this 44-hour aggregate time span, with tweets originating in Metro Louisville representing 55%, 66% and 60% of the total number of tweets with the hashtag during the three periods, respectively. In other words, talk of the purge spread quite slowly over the course of the week.
Time #1: 42 tweets
From August 13th at 11:30pm to August 15th at 6am
Time #2: 36 tweets
From August 15th at 6am to 4pm
Time #3: 104 tweets
From August 15th at 4pm to 8pm
The number of tweets with the hashtag exploded right around 8pm on Friday night, the 'official' start time of the purge. This four hour time period represents the peak of tweeting activity around #LouisvillePurge, attributed largely to the fact that this is when the event started to diffuse outward beyond the city's boundaries to places both near and far. One can see both a significant increase in the amount of tweets across Kentucky, as well as to far-off cities like Los Angeles, Milwaukee, D.C., Philadelphia and New York City. From 8pm to 12am, the 757 tweets from Metro Louisville represent only 30% of the 2,533 tweets across the country, further highlighting the spatial diffusion of information about, and interest in, the purge. In fact, this measure of locally-concentrated tweeting drops even lower to less than 10% from the hours of midnight to 6am (when most Louisvillians would be asleep), though it again rebounds a bit higher to 23% during our final time span of 6am to noon on Saturday the 16th, after the purge has 'officially' ended.
Time #4: 2,533 tweets
August 15th at 8pm to August 16th at 12am
Time #5: 1,420 tweets
From August 16th at 12am to 6am
Time #6: 216 tweets
From August 16th at 6am to 12pm
Like our earlier research on #LexingtonPoliceScanner in the wake of the 2012 Kentucky Wildcats basketball championship, we can clearly see an ebb and flow in the way the event originates in a fairly localized area before gaining a larger following and eventually slowing down and becoming more localized again as many users reflect upon the aftermath. But unlike the attention paid to the #LexingtonPoliceScanner in large cities around the country, and especially the South, the interest in the #LouisvillePurge tended to be somewhat more diffuse, without any single location outside of the city or state paying a disproportionate amount of attention to the events.
In the end, we're happy to report that all of the Floatingsheep emerged from the purge unscathed and thoroughly amused, and we hope the same can be said for all of you and your loved ones. And do remember, don't trust everything you read on Twitter [3, 4]!
 Again, it's probably worth noting -- somewhat ironically, I suppose -- that despite the rumor originating and being passed around via social media, it was the traditional local television news networks whose willingness to believe and highlight the rumor drove further attention to the situation, which was almost obviously a farce from the very beginning.
 You can also access an animated GIF version of this time series map here.
 Especially if you are supposed to be a "real journalist"!
 For that matter, don't trust everything you see on the television news, either!