"More Sex is Safer Sex" Paradox (Python)
code.activestate.com
code.activestate.com
http://www.soc.duke.edu/~jmoody77/chains_pressfigure1.jpg
You've got a lot of two-person monogamous pairings, a smaller number of triads, scattered chains, and then this BIG, HAIRY THING that's vaguely ring-shaped. It doesn't have promiscuous hubs; you can stop the spread of STDs by trying to get as many people as possible to use condoms and get STD screening, thus breaking the chains. It's almost a spanning tree.
This structure can be generated from two simple rules:
1. People tend to date other people with a similar amount of past sexual experience.
2. People avoid dating the exes of other people who are close to them in the relationship graph, since this makes them look bad to their friends, exes, and so on. This accounts for the lack of short cycles.
This was theoretically confirmed by some researchers who wrote computer simulations to try to come up with similar-looking relationship graphs, and succeeded brilliantly:
Here's a real sex graph;
I mean seriously. Half the folks who often have sex will have AIDS?
Further, one can think of intuitive reasons that the conservatives having more sex might help. e.g. it lowers the chance of an STD going from a high risk person to a high risk person (which would cause it to be spread way more after). I have no idea who that makes right, I'm just saying intuitively one can think of simple reasons it might go either way and so the details definitely do matter.
It is more plausible that the number sexual partners follows a Pareto distribution. It is likewise plausible that the economist sought to flatten the Pareto curve, even if this may result in the area under the curve increasing somewhat. Would it work? Maybe not. But this counterexample just reflects badly upon us. Programmers are the new physicists of this era.
If you really want to take the economist up to task, you should find his paper, code his model and parameters exactly, see if you reproduce his hypothesis over a number of trial runs (for all we know, he may not have run a sim at all, given the NYTimes' shoddy reporting).
My model does have a number of flaws (a uniform distribution is still not very good; there's no gender distinction; the transmission rate per encounter is artificially high; people only stay with their partners for a random-yet-uniform amount of time) but I'm not sure to what extent these matter.
This agrees with your first figure:
About one in six Americans (17%) had the genital herpes virus -- called HSV-2 -- during 1999-2004. But that is down from the 21% rate seen in 1988-1994.
But then closes with this, which seems very real world relevant to this thought experiment/theory/whatever you want to call it:
As its name suggests, HSV-2 isn't the only herpes virus out there. HSV-1, the virus that causes cold sores, is much more common. As of 1999-2004, 57.7% of Americans carry the virus -- down slightly from the 62% HSV-1 infection rate seen in 1988-1994.
There's some bad news here: HSV-1 is causing more genital herpes than ever before. About 2% of people with HSV-1 infection -- but not HSV-2 -- have genital herpes.
"Our findings are consistent with previous reports that genital herpes caused by HSV-1 may be increasing in the United States, as in other developed countries," Xu and colleagues note.
The researchers warn that the herpes virus that causes cold sores may one day become a more important cause of genital herpes. One factor: The increase in teen oral sex that's helping stop HSV-2 spread may be increasing genital infections with HSV-1.
In this particular system, the parameters matter, but not very much for the particular question the author was asking. The system is well-behaved; it doesn't bifurcate or go chaotic. Tweaking the parameters will change whether the final level of infections is 10% or 90%, but the overall conclusion that "sexual conservatives taking more partners increases total infections" remains valid.
People will whine and moan about the privacy concerns, but when it comes right down to it people with untreated or untreatable STIs should not be having sex (and if they are their partners should be made aware.)
Why "not be having sex" and not "not be having unprotected sex"?
Really, there's nothing wrong with them having sex - just so their partners are aware of the risk.
Also, there are no HPV screening tests for men.
So while I agree with some of your points, I really don't think a card or test will address the issue. For one thing, if someone asked me to produce my card (or latest test results), to me that would just scream "This is just a hook-up. You are nothing but a sex object to me." At which point, if I did the traditional dating thing, I imagine I would get up and leave the table. For another, different people have different levels of understanding of what the risks are. So I would question what it means for their partners to be "aware of the risk". Do you just give them notice of your state of health or do you have a larger obligation than that to ensure they REALLY get it? Just giving men notice of my state of health struck me as wholly insufficient. They blithely climbed into bed with me anyway (and without a condom), apparently oblivious to the potential implications of sleeping with someone who was deathly ill with something doctors did not know how to effectively treat (or even really identify).
Also, the "high-activity players" modeled as 1 per 10 days seems pretty low, to me. In an extremely conservative society using prostitutes as a sexual outlet for unmarried young men, I would expect rates in excess of 10 per day, not 1 per 10 days.
No sex is the safest kind of sex.
Not sarcastic and not that I am celibate- but if you personally really wish to avoid STD's, there is a very clear solution.
Also, I'm not quite humanitarian enough to raise my personal risk exposure for the sake of lowering society's risk exposure.
I hold it true, whate'er befall;
I feel it, when I sorrow most;
'Tis better to have loved and lost
Than never to have loved at all.People will have sex.
So it really doesn't matter if it isn't totally safe.
If your comparing the two options of
* Low risk wiser people increasing their risk and acting less wise so that high risk less wise people can have their cake and eat it to
* Or High risk less wise people lowering their risk and acting more wise.
He also misunderstands the dating pool. It isn't as if promiscous people have a calendar and go to the bar determined to hook up with someone every 100 days, then when they're done think "that was nice, I'll do that again in 3 months." They go to the bar frequently and hook up every time they get the opportunity. Hookups with less promiscous partners don't sate their appetite or reduce at all the number of hookups they'll make later.
I believe the Hardy story is told in C P Snow's foreword to A Mathematician's Apology, and the result is now well known: http://en.wikipedia.org/wiki/Hardy–Weinberg_principle
I'll check back when I'm less busy to compare how our simulations are set up. Mine was very quick and dirty and naive, based on uniform random distributions no less, so I'm fully open to the possibility we're both wrong.
He was saying that it is in your personal best interest to convince people more sexually conservative than you to start having more sex, which reduces your individual risk. I don't remember him making any claims about the overall benefit (or lack thereof) to the population except for the admittedly misleading title of the book and example.
I have no idea whether the claim he did make is true or not, but this particular program doesn't get us any closer to finding out.
This really doesn't sound logical to me unless the goal is to specifically talk some conservative individual into being your long-term sex partner, thus securing a source of sex with a low risk of a) bringing an infection into the equation to start with and b) exposing you at a later date due to promiscuous behavior after they start sleeping with you. Of course, that assumes you also "behave" once you have such a situation or all bets are off. (I think most cultures already place a pretty high value, at least theoretically, on such an arrangement via valuing monogamy and marriage.)
Actually, it never was, since that's not what paradox means in the first place.
But he did show it wasn't true at all.
But even if he hadn't, it would -never- have been safer for the 'sexual conservatives'. More sex always means more risk for them, no matter the time frame.