Knowing People's Minds

What are people more concerned about: Terrorism or Global Warming?

A tool in development by google, still with clipped wings to prevent privacy concerns, allows a new way of answering this kind of question. If we define “people” to mean a weighted average of humanity in proportion to how much time is spent googling issues of concern, then google trends, by telling us the relative frequencies for different search terms entered into google, allows us to know their concerns. Here are the results for 2004 and 2006 in the United States (you can restrict results by region and date, though the functionality is still limited):

What I find fascinating about these graphs is that, first, they identity a cross-over. In 2004 “terrorism” was searched for more frequently than “global warming”, but by 2006 they had switched places. It is not clear how significant the difference is, since google does not provide a scale, though my guess would be that it’s logarithmic. A second insight, apparent by the bottom “news reference volume” graph, is that the news is heavily skewed towards reporting terrorism relative to global warming. In 2004, where “global warming” was nearing “terrorism” in searches, its news volume barely left the x-axis (there is no scale or numbers provided, presumably for privacy concerns). By 2006 the volume of news reference to “global warming” was catching up, but as is apparent by the next graph spanning 2004-2007, they are still greatly disproportionate.

There are severe limits to inference with google trends. A keyword might have other referents. For example, trying to determine which university (Berkeley, Stanford or Yale) is most popular would seem to give the prize to Berkeley. However, Berkeley’s search volume is probably helped a bit by the city (and doubtfully, philosopher) sharing its name.

Furthermore, it’s not clear exactly what it means that someone searches for a specific word. Someone could search for “terrorism” because they are interested in participating in or opposing terrorism. All google trends can tell us is the approximate relative magnitudes of the frequency of various searches over time and by region. It’s a good start.

-Allan