Statistic: “More Than 1,000 Mexicans Leave Catholic Church Daily”

Statistics are often put into terms that the average citizen might understand. Or, more cynically, into terms that grabs attention. Here is an example from a sociologist/historian looking at data about Catholicism in Mexico:

More than 1,000 Mexicans left the Catholic Church every day over the last decade, adding up to some 4 million fallen-away Catholics between 2000 and 2010, sociologist and historian Roberto Blancarte told Efe.

Put this way (and a headline built around this daily figure), this statistic seems noteworthy as it looks like a lot of people are making this decision every day. But later in the article, we get a broader perspective:

In 1950, 98.21 percent of Mexicans said they were Catholic, in 1960 the percentage dropped to 96.47 percent, in 1970 to 96.17 percent, in 1980 to 92.62 percent, in 1990 the percentage dropped to 89.69 percent, in 2000 the country was only 88 percent Catholic, and now that percentage is lower still at 83.9 percent.

This signifies that the last decade has seen a drop of more than 4 percentage points, equivalent to almost 4 million people or an average of 1,300 people a day leaving the Catholic Church.

From this decade-by-decade perspective, there is a clear decline from 98.21 percent to 83.9 percent in 2010, a drop of just over 14 percent over 60 years. But this longer-term perspective also helps show that the daily average isn’t really that helpful: are there really 1,300 people each day that make a conscious decision to leave the church? Is this how it works among individual citizens? In this case, it might be better to look at the percentage change each decade and see that the 4.1 percent drop in the 2000s is the largest since 1950.

Additionally, can the average person easily envision what exactly 1,300 people means? This is a large room of people, bigger than even a decent size college classroom but not quite enough to fill a decent sized theater. The Metro in Chicago holds about 1,150 so this is a close approximation.

At least we didn’t get down to another type of common statistic: this data from Mexico breaks down to about 1 Catholic leaving the church every 1.11 minutes.

Using Twitter as a data source; examining emotions and more

In April, the Library of Congress announced plans to archive all public tweets since the start of Twitter in March 2006. So what might researchers do with this data?

A recent study provides an example. Scholars from Northeastern and Harvard examined the emotions of Americans through their Tweets. By coding certain words as having positive or negative emotional value, researchers were able to map out data. According to New Scientist:

[T]hese “tweets” suggest that the west coast is happier than the east coast, and across the country happiness peaks each Sunday morning, with a trough on Thursday evenings.

The mood map is cool.

While the findings about when people are happy may not be too surprising, the research does bring up the question about the value of Tweets as a data source. Since it is likely skewed to a younger sample and also perhaps a wealthier and more educated group, it is not representative data. But it could provide some insights into reactions to certain events or for seeing the beginning and end of certain trends.

So what else will researchers study using tweets?