Tuesday, January 27, 2009

Teenage Sex Stats

From the Latest Well Article from Tara Parker-Pope:

Today, fewer than half of all high school students have had sex: 47.8 percent as of 2007, according to the National Youth Risk Behavior Survey, down from 54.1 percent in 1991.

A less recent report suggests that teenagers are also waiting longer to have sex than they did in the past. A 2002 report from the Department of Health and Human Services found that 30 percent of 15- to 17-year-old girls had experienced sex, down from 38 percent in 1995. During the same period, the percentage of sexually experienced boys in that age group dropped to 31 percent from 43 percent.

About 16 percent of teenagers say they have had oral sex but haven't yet had intercourse.

"I give presentations nationwide where I'm showing people that the virginity rate in college is higher than you think and the number of partners is lower than you think and hooking up more often than not does not mean intercourse," Dr. Bogle said. "But so many people think we're morally in trouble, in a downward spiral and teens are out of control. It's very difficult to convince people otherwise."

I wonder how these sex rates compare to the 1960s and 70s. Have rates significantly increased or are parents just hypocrites? While the given oral sex statistic is interesting, I wonder how many sexually active teens engage in oral sex. It sounds like the article is assuming that basically all of the sexually active teens engage in both.

Friday, January 23, 2009

Ryan Howard's Arbitration Case

I have been frequenting fangraphs.com recently, which is a great site for lots of cool baseball data and analysis. I recommend it for all the baseball stat nerds out there.

Recently Ryan Howard, the Phillies first base slugger, is in the news for having the biggest difference between arbitration figures submitted. Howard is asking for 18 million, while the Phillies submitted a figure of 14 million. Last year, in his first arbitration year, Howard took home a record 10 million for actually taking his case to arbitration judges and winning.

So in terms of arbitration, major league players have three arbitration years. Howard is in his 2nd year. According to Fangraphs, estimates on what players get are 40% of their free market value their 1st year, 60% their 2nd year, and 80% their 3rd year. So Howard should be getting about 60 percent of his free market value.

The Phillies with their 14 million dollar offer, think Howard is worth 19.6 million/year.
Howard with his 18 million dollar suggestion, thinks he's worth 25.2 million/year.

So basically Howard thinks he deserves the 2nd highest contract in league after ARod, who makes 27.5 million/year.

Looking at Fangraphs data, here are what the top Phillies were "worth" based on last year's production:

1. Chase Utley: 35.7 million
2. Jimmy Rollins: 23.1 million
3. Jayson Werth: 21.3 million
4. Cole Hamels: 20.6 million
5. Shane Victarino: 17.0 million
6. Ryan Howard: 14.1 million

The stats take into account his defense, replacement level (1b) performance, OPS (which went down .100 this year), and many other measures.

Howard has regressed the past three years, but considering his great 2nd half he will hopefully preform better next year. The Phils take that into account giving him a "19.6 million/year" deal (5.5 million more than he "made" last year).

Yes - Howard wants the 2nd "highest" salary in the major leagues, when he was potentially the 6th most valuable Philly last year.

It will be interesting to see what happens if this goes to arbitration. Do these arbitration judges think like MVP voters (Howard finished 2nd in NL MVP voting) or do they take into account statistics other than HR and RBI? I think either way Howard will lose his case.

A good point (by a fangraphs contributor) was made that needs to be considered.

He basically believes that Howard cannot be considered like a typical arbitration case, which would normally fall under the 40/60/80 rule. The problem with Howard is that the Phillies took awhile (age 26?) in calling him up (since they had Thome). Assuming the arbitration judges aren't ignorant like MVP voters, they probably rewarded Howard 10 million last year because he really should be in his 3rd year of arbitration (not his 2nd). I can understand that logic a bit more. If you make that assumption, Howard only thinks he's worth 21.6 million, which is a bit high but more understandable. In the above article, the fangraphs author used 2009 projections to calculate that Howard would be worth approximately 15 million (assuming he's in his "third" year of arb.)

So it could go either way I guess, but I still don't think he's worth the money.

Stat of the Week: Hospitials as Hotels

According to a paper from the National Bureau of Economic Research

"We also find that a one-standard-deviation increase in amenities raises a hospital's demand by 38.4% on average, whereas demand is substantially less responsive to clinical quality as measured by pneumonia mortality."

-It's interesting they used pneumonia mortality as a measure of clinical quality. I can only read the abstract, but I would assume that they adjusted for confounders and such like a good epidemiologist would do.

Media Attention and Risk Perception

From a Freaknomics interview of author Ben Sherwood:


Can a positive outcome to a crash like USAir 1549 change often unrealistic public perceptions of the fatality of plane crashes?


I doubt it. It’s incredibly safe to fly — your chances of dying on your next domestic flight are just one in 60 million — but many Americans are still petrified of air travel.

It’s no surprise: Plane crashes monopolize media coverage. Indeed, one MIT study found that airplane crash coverage on the front page of The New York Times was 60 times greater than reporting on HIV/AIDS per 1,000 deaths; 1,500 times greater than reporting on auto hazards; and 6,000 times greater than cancer.


Now, the key to this passage is they only looked at the front page. Still, it's very interesting and telling on why our perceived risks rarely match the actual risks.

Monday, January 12, 2009

Our (Potential) Future Surgeon General and Marijuana Legalization

Before I begin, I implore to you watch this Daily Show clip on Dr. Gupta. Aasif Mandvi does a great job. I hadn't laughed that hard in awhile. (start at minute 2 for the good stuff)

Anyway, Dr. Gupta recently wrote an article for Time Magazine entitled "Why I would vote No on Pot". I'm
pretty disappointed in this article by our (potential) future surgeon general. He brings to light both sides of the issue, but I don't think he argues his case very well.

So what did he bring up in the article (which leaves out other valid arguments for both sides):

positives of legalizing pot

- can help really sick people - those going through chemo, and those suffering from Alzheimer's
- 15 million people all ready use it, so wouldn't have to enforce law on them
- cut illegal drug trafficking and make communities safer

negatives of legalizing pot
- addiction
- affect short term memory
- impair cognitive ability
- lead to long term depression or anxiety
- can impair driving - cause accidents

First off I am disappointed by the lack of statistics. From this article I have no idea how severely pot affects short term memory, leads to long term depression, etc. A reasonable question would be, how do these negatives compare to alcohol? It seems that alcohol shares all of these negative consequences and is potentially worse in some cases. He also suggests outcomes that are rather subjective like depression, cognitive ability, etc. It is not nearly as clear cut as tobacco's relationship to lung cancer and other disease. I don't doubt his medical claims, but he should at least link to scientific/epidemiological studies supporting it.

So how authoritarian is Sanjay Gupta? Yes, it would be better medically if we banned alcohol and soda - but is it the right move for the country? There are reasonable reasons to keep marijuana illegal, but Dr. Gupta needs to bring a little more substance to his argument. Granted this was just a short article for Time Magazine, but adding links similar to Frank Rich's style at the New York Times would be refreshing.

One of my major reasons for reluctance of Gupta for Surgeon General is his lack of public health training or experience. If this is the way he would describe a public health epidemic in the future as surgeon general, consider me unimpressed.

Looking further at the Marijuana issue as a whole:

Gallup polling has explored the legalization of Marijuana question for years, and while support is still on Dr. Gupta's side the margin is eroding.

When asked if medical marijuana should be legalized, support jumps into the 70 percent range. Dr. Gupta points out that 11 states have all ready decriminalized marijuana for medical use. I honestly believe that polling (on legalization of both medical and recreational) would change if people were more informed on this subject.

For example, there is a very valid economic argument that would play well in today's economic situation.

Jeffery Miron an economist from Harvard conservatively estimates that the US could receive 14 billion dollars a year from the legalization of marijuana. "...the government would save $7.7 billion a year if it didn't have to spend money policing and prosecuting marijuana activity. Then, if the feds taxed marijuana at a rate comparable to cigarettes and booze, another $6.2 billion would come rolling in."

It will be interesting to see if any "change" is made on this issue with the Obama administration, considering it's the "#1 Idea" proposed on their site change.org.