Recent headlines suggested that heavy Facebook users had lower grades, citing a study done at Ohio State.

Well, that sounds interesting. What student doesn't have an account these days? It's probably easier to count non-Facebook using students than those with an account.

Even semi-older codgers like myself enjoy the site, although my four student children get a lot more use out of it than I do. For example, I have a grand total of maybe three pictures posted. My eldest son had, at last viewing, more than 1,300.

So when a study comes out that says heavy Facebook student users get lower grades, that's sure to catch a parent's attention.

Except the stories lacked a lot of context and not enough detail about the study, says Carl Bialik, who writes one of my favorite columns, "The Numbers Guy," for the Wall Street Journal.

The problem, according to Bialik, is that the study only went so far and did not draw a direct line between heavy users and lower grades; even if Facebook shut down, those poorer students might have found other ways to fritter away hours they might have more profitably spent studying. (Frisbee, anyone?)

How much money does your community spend on "culture"? This week's "Your Town" list is dominated at the top and bottom by small communities.

Culture, btw, is defined by the Dept of Revenue, which collects the information, as money spent on libraries, celebrations, and parks.

"Many Eyes" is software that I've been playing with that allows users to visualize data. It's a pretty interesting experiment and a lot of fun. Here's an example using the cost of municipal government per capita.

I like Many Eyes because it's easy to see which communities are the outliers and which are in the middle of the pack.

This is something I'll be playing with a lot more in the future.

The word "average" is used all the time, with all sorts of numbers and data. But it still can be confusing to people, who get confused about the differences between average, mean, and median.

Here's an interesting BBC commentary on why most people have an "above average" number of feet.

The Department of Education collects information about the number of minority teachers in each district.

It makes for an interesting chart. Note that I used the state median, rather than the average. I often use the average, but didn't in this case, bc it distorted the results. The average is much higher than the median, but tha'ts bc big districts such as Boston have so many teachers.

I was more interested in the results for individual districts, so stuck with the median.

btw: Now that it's posted online, I wish I'd made a change: I should have included more info, such as breakdowns by race, which was available. Oh well, live and learn. Next time.

How much is too much to pay for property taxes? Depends on the individual, of course, and what level of services they want in return for either higher or lower taxes.

This week's Your Town chart of average property taxes on single-family homes shows that the highest average taxes are paid for in a cluster MetroWest communities -- Weston, at $15,293, followed by Sherborn, Dover, Concord, and Carlisle.

The state median is $3,573.

I'm a big fan of the online statistical graphics in the New York Times. They put in a lot of time and care, and it shows. Today is no exception. The graphic accompanying the story on falling home prices is informative and slick at the same time.

The bar chart shows home price changes in 20 major cities (including Boston) from 2001 onwards. Moving from one city to the next is a breeze and quickly demonstrates housing's boom bust cycle dramatically, especially in cities in the South and West.

In these tight times, I'm a devoted shopper of thrift shops, especially for men's ties. Why spend $30 when a buck will do?

Of course, the selection is more limited than at a department store, and is limited further by my own rule – don’t buy unless the tie is like new.

So I was struck recently by the color of two ties I purchased recently -- both were dominantly green. Thinking back, I realized a large percent of the ties I purchased at thrifts were mostly green.

This isn’t because I particularly like the color, either. My color tastes in ties run the usual conservative gamut of blues, reds, and yellows, and for the usual reasons. Green ties are harder to match to shirts, which tend to be whites and blues.

Curious now, I examined the tie rack and found that, statistically speaking, most of the ties followed the usual predominant color conventions of reds, blues, and yellows. Those also tended to be the most beat-up, so were the ones I would most likely skip.

Which led me to my Green Tie Bargains at Thrifts Theory: Men don’t wear green ties as often because they are more difficult to match to shirts. Hence, when men get sick of their ties and bag a bunch for the thrift, the green ties tend to be in better shape.

So if you’re looking for a bargain on a tie – especially one that’s green– the odds favor shopping the thrifts.

Any thoughts? Or even crazier theories?

The Your Town chart this week checks in with the number of public employees per 1,000 residents -- a nice chart for people to compare their town with other communities. As usual, there are some nuances with the numbers that aren't always apparent at first glance.

For instance, the rankings are dominated by small towns -- Gosnold, Rowe, and Monroe, for instance.

While it might seem at first glance these towns are top heavy with workers, it more likely reflects that the towns have small populations, so even a handful of employees is supported by not many residents. Also, some of these towns are vacation communities, where the summer population swells with tourists, although they would not be counted in an official census.

Love it or hate, snow is fact of life in Massachusetts. Some people dream of ski slopes; others dread every flake and can't wait until Opening Day at Fenway. Either way, your community needs to clear the streets, and that's not cheap.

This Your Town chart shows how expensive it was in your town to plow the streets. The cost is per person. The state median was $29.

There's a clever program out there called 'Wordle' that uses word counts to create cool statistical images. To use the program's own description:

Wordle is a toy for generating “word clouds” from text that you provide. The clouds give greater prominence to words that appear more frequently in the source text....

It's a very interesting visual way to see what words are used the most often in a story (or anything else), giving the viewer a quick idea of what is most prominent. The program is free. Here's an example of what Wordle does to a story on police details I wrote:

The New York Times has an interesting story on an open-source program, called "R," that is being heavily used by statisticians. I'm not familiar with the program, but would like to hear from people with experience using it. Is it as good as advertised? What makes it so powerful?

It's fun when your community tops a chart; it gives you a sort of bragging rights ... usually. Sometimes, though, there are times when no one wants to be the "winner." Take, for instance, "Inmates per community," which will be the Your Town chart posted Jan 8. Any guesses which communities top the list?

If you guessed Springfield, Holyoke, and Lawrence, you'd be right. About 60 communities had no inmates in the state system.

(Note: Your Town is now posted.)

The state Department of Education seems to track how every dollar is spent by public school districts -- including money spent on guidance, counseling, and testing.

Among those spending the most, for some reason, appear to be regional school districts. The state median was $317. To see where your school district fits in, check out the "Your Town" chart for this week.

Matt Carroll

Teaching has traditionally been the domain of females, but that has been changing, although slowly.

Take a look at this "Your Town" chart: Out of more than 380 school districts statewide, only nine have more male teachers than female, and all are either vokes or charters.

Actually, the list of the 25 schools is dominated by vokes, led by Greater Fall River Voke and Upper Cape Cod Voke, with more than 55% male teachers.

Matt Carroll

Broken down this week for the Your Town chart are jobless rates for each community in the state.

Considering that the Oct 07 rate statewide was 3.9% unemployment, it's no great surprise that a year later the rate has jumped to 5%. Lawrence had the worse rate in the state, at 11.2%.

Smaller communities in western Mass. had the lowest rates, hovering around 2 percent. Closer to Boston, towns like Dover and Lincoln had rates of 2.8%. Almost every community was up from a year ago.

This is a blog about numbers, but that doesn't mean we have to be serious *all* the time. For instance the other day, I was arguing with my daughter about the popularity of the name "Jane" in rock music songs. (We were listening to "Jane Says" by "Jane's Addiction's.")

I argued the name "Jane" was very popular, pointing out, off the top of my head that Velvet Underground had used the name as well as ... Well, actually, I was stuck after that, and that's where my daughter's eye rolling began.

But it got me wondering, in a stat-geek sort of way: What are the most popular personal names used in songs or song titles? Has anyone ever seen a chart or database broken down like that? It could be quantified in a number of different ways of course; anyone have ideas on how to do it?

Matt Carroll

When researching today's story on local pension funds, I noticed most government pension funds in Massachusetts are sorely underfunded -- meaning they don't have enough money socked away to meet the current obligations to current and future retirees.

That raises an interesting question: How do Massachusetts funds stack up against their peers? It turns out Massachusetts cities, counties and towns appear to be in worse shape than most public pension plans nationwide, even though Massachusetts government workers contribute between 5 and 11 percent of their paychecks to the pension plans in lieu of Social Security (significantly decreasing the burden on local government).

Before the year began, local public pension systems in Massachusetts were just 65 percent funded on average, according to the Public Employee Retirement Administration Commission. By contrast, a survey by Wilshire Consulting of 104 city and county retirement systems around the country found plans were 93 percent funded on average as of mid-2006. A separate study by the National Association of State Retirement Administrators of 125 state and local pension funds found those funds were 86 percent funded as of mid-2007. (As a rule of thumb, experts say pensions should generally be funded by at least 80 percent.)

So why are Massachusetts funds in worse shape than other government pension funds? More after the jump.

FULL ENTRY

The latest Your Town chart is school district SAT scores for 06-07. The scores are either dreaded -- by some students -- or keenly anticipated -- by parents eager to find out where there child and school district rank.

There are three tests -- Math, Reading, & Writing -- each with a top score of 800. The Globe ranked the districts by total avg score.

There are some surprises, especially at the top of the heap:

Ma Academy for Math and Science 1987
Boston Latin 1866
Lexington 1863
Acton-Boxborough Reg 1855
Weston 1841

For more about where yr school district stands, check out the chart posted tomorrow on the Government Center page or read in your local Zone edition.

Matt Carroll

Like other households in Greater Boston, my family has become pretty good recyclers. Boston, where we live, recently adopted the "single-stream" concept, which means everything recyclable goes into one bin. That's encouraged us to recycle even more, which got me thinking -- how much does the average person recycle, anyways?

That was the genesis of this week's Your Town, which is the average amount of recycling done by households (with the caveat that the numbers may have some commercial mixed in).

If you look at the figures, one town jumps out: Danvers, where the average was more than 47 pounds a week, far and away larger than anyone else. It was so out of whack I called the town, asking if the figure was accurate.

They were, I was informed, but the number was a fluke. What happened was a major flood, which wrecked a lot of washer machines and dryers in basements. These, being metal, were also recycled, but pushed up the average dramatically for the year.

Matt Carroll

One of the fun things about doing a weekly chart such as "Your Town" is that you pick some slightly goofy factoids to post. This week it's library lending and which libraries do the most lending per capita. Who even knew this data was out there? I ran across it while doing a story on how libraries are changing in the digital age. (One change: many many more DVDs going out the door.) The data is online, as well in the Globe's regional papers today. (If you get the City edition on Sunday, it will be in then.)

Anyways, the communities with the heaviest lending, with 17 or more books or periodicals lent per person in 2006, are: Dover, Hamilton, Acton, Carlisle, and West Newbury. The lowest: Lynn, Chelsea and Revere, with less than one periodical per resident.

Matt Carroll

I do the "Your Town" charts that run on page 2 of Thursdays' regional editions. This week, because of the election, we ran an obvious one -- how towns voted on the 3 referendum questions. Anyways, we're always looking for ideas -- so if you have some cool ideas that can be turned into to a town-by-town chart, let me know by posting a comment. If the data is out there, I'll do my best to get it done. btw, we give a credit line to people who come up with ideas that make the paper or go online, if the person wants that.

Matt Carroll