Saturday, June 30, 2012

spider sighting

Found this spider outside my front door yesterday morning:

The community at (because, as it turns out, there are people whose idea of fun is looking at other people's grainy cell phone pictures and trying to identify the spiders depicted therein: how did people live before the internet?) identified it as a wolf spider, but I didn't think the eye configuration looks quite right.

Friday, June 29, 2012

Molecule of the day: tripropionin

The molecule of the day is tripropionin:

It can be used as a soluble substrate for pancreatic lipase.

I would probably call it TriC3: a triglyceride of chain length 3.

Monday, June 25, 2012

Sun letter follow-up

On the one hand, the Sun published my letter; on the other hand, their editorial choices reveal that they completely missed the point.

I don't even know why they need to tamper with it at all: it can't be in the interest of conserving space, because then why replace parentheses with two m-dashes and the word "incidentally"?  I think it's quite audacious to start throwing unsolicited adverbs into other people's writing.

But let some good come of this incident: no more will I blame the authors of any idiotic letters I find printed in the Sun, for I know that the editors probably just butchered a letter that had once been filled with subtlety and nuance.

Wednesday, June 20, 2012

letter to the Sun: liquor store and crime correlation

In which I once again link all of our city's problems to a lack of STEM education:

Dear Baltimore Sun,

The city health officials who plan to strip non-conforming liquor stores of their licenses because of the Johns Hopkins University study linking them to violent crime (“City Targets Liquor Stores”, June 17 [warning: pay wall]) are confusing correlation with causation.  It could be that the liquor stores themselves are not causing the crime, but rather that some other underlying cause is causing both the non-conforming liquor stores and the violent crime.  The distinction is important, because if the liquor stores are not causing the crime, then closing them would not actually be predicted to decrease violent crime, and could even exacerbate it.

As it turns out, property vacancy also correlates with violent crime (for example, Goodstein, Ryan and Lee, Yan Y., Do Foreclosures Increase Crime? (May 2010). Available at SSRN: or  If a non-conforming liquor store loses its license, it seems at least as likely that the store will end up as a vacant property than that the owners will decide to open a healthy food store in its place, as the city officials hope.

Before taking away licenses and, as a consequence, closing small businesses (that would furthermore disproportionately impact a particular ethnic group), the city needs to carefully consider the evidence to determine whether the benefits of doing so really are predicted to outweigh the costs.  This story once again emphasizes the importance of having a basic mathematics education (for no student in the first week of an introductory statistics course would confuse correlation with causation), both for our city officials as well as for our journalists.