Friday, February 20, 2015

Ride the bus!

I wish that it was this awesome when I ride the bus.

From 2012

From 2015

Thursday, February 19, 2015

Thursday Thoughts: VMAP0 shapefiles for Chile?

Presently, I'm working on creating some GIS-based analyses of Chilean rivers and river ecology. However, Chile being Chile, a lot of the data (both GIS data layers and river ecology data) are not readily available. Therefore, in order to get GIS data, I have to find whatever publicly available GIS data are online and use those.

I spent the last week developing a hydrology layer from a relatively high quality DEM, and - happily - the results of deriving hydrology from a DEM were generally confirmed by lower-quality GIS layers of water courses. (I used these lower-quality layers to assess the quality of the DEM-derived layer).

Now, though, I have encountered the problem of not being able to find a good surficial geology layer for the watershed I'm studying. I'm sure that there must be something out there, but I can't find it. I'll have a talk with some people in the lab once the summer break is over, but I wanted to start on something today. Well, after a rummage around, I found nothing usable, and so I turned back to the central source of GIS data layers that I used for my master's research: VMAP0.

Although it's somewhat old (and that's an understatement), VMAP0 does provide a decent (if somewhat coarse-resolution) data source for those data layers that don't change too quickly over time (like geology). One thing that I had forgotten was that VMAP0 is in a file format that I can't use in QGIS (which is the GIS program I'm using while I wait for the summer break to be over and I can get someone from IT to set up a remote connection to the university's license server).

Well, after a couple of searches, I found that someone had already converted all the VMAP0 regions into "shapefile" format. Harasho to the guys at GIS-lab!

EDIT: ... and it turns out that VMAP0 actually doesn't have geology layers. Darn. Well, back to the search.

Wednesday, February 18, 2015

Wednesday Omphaloskepsis: Will combining two forms of birth control increase overall birth control effectiveness?

Screen capture taken from, which shows the first two of three rows of the interactive graphic from the NYTimes article "How Likely Is It That Birth Control Could Let You Down?"

A friend of mine posted a link to this article on the effectiveness rates of various forms of birth control, from highly ineffective methods, such as fertility awareness based methods (i.e., the rhythm method) and withdrawal (i.e., “pulling out”) shown above, to highly effective methods, such as female sterilization (i.e., a hysterectomy) and male sterilization (i.e., vasectomy), not seen in the graph above. All of these statistics were presented as increasing rates of getting pregnant over a 10 year period, so the reader could directly compare the cumulative rates of pregnancy over time. An interesting thing is that some of the graphs show the differences between the "optimal" and "typical" rates of getting pregnant. Some of the methods, such as "spermicides" and "sponge (after giving birth)," show optimum curves that are not that better than typical curves, while other methods, such as "Pill, Evra patch, NuvaRing" and "Depo-Provera" show major differences between the optimum and typical curves. This indicates that some methods are minimally impacted by "human error" (e.g., improper use of spermicide or improper placement of the sponge), while others heavily impacted by such errors (e.g., using the Pill irregularly).

(A note to my fellow pedants: Here, I will be only considering the final (i.e., 10 year) rate, and so instead of referring to a chance of “X in 100 over 10 years,” I will refer only to a chance of “0.0X.” Yes, I know that there is a difference between “X in 100 over 10 years” vs. “0.0X,” but I don’t want to write “X in 100 over 10 years” over and over in this entry, and I assume that the reader doesn’t want to read “X in 100 over 10 years” over and over in this entry, so let’s just recognize that when I write “0.0X” in this entry, I implicitly mean “X in 100 over 10 years.”)

Interestingly, the most effective method on their chart wasn’t sterilization (which had a rate of 0.05 for women, and a rate of 0.02 for men), but actually a hormonal implant (which has a rate of 0.01). This raised a question in my mind: would it be possible to combine birth control methods in order to diminish the overall chance of getting pregnant? It is quite alluring and – on the surface – seems to make perfect sense.

Well, the more I thought about it, the more the answer was: it depends.

Although it's been several years since I studied reproductive physiology, I suppose that there would be some increased effectiveness if a couple combined two or more methods. Statistics indicates that, if the two methods were truly independent, then you multiply the two rates together (much like the chance of rolling two sixes with two dice is 1/6*1/6=1/36 and not 1/6+1/6=1/3). Therefore, if the woman uses one method and the male uses another method, then we can assume that the two methods are independent of each other, thus allowing us to multiply the two effectiveness rates together. Therefore, if a woman is using only spermicide (0.94) and if her male partner uses only the withdrawal method (0.92), then the possibility of pregnancy IS lower than the use of one of those methods alone (0.94*0.92=0.88); slightly worse than male condom alone (0.86).

However, if the two methods are not independent (like withdrawal and male condom), then one cannot simply multiply the two rates; an additional correctional factor must be multiplied to account for the codependence inherent in the two methods. Two additional hitches: (1) we don’t know what that correctional factor is, and (2) it will likely be different for each combination of codependent methods. However, even though we don't know what any of these correctional factors are, we could make the assumption that no two birth control methods will be synergistic (i.e., no correctional factor would be >1), which means that multiplying the two rates together produces an indication of the best potential effectiveness for typical use. Therefore, if the male partner uses both withdrawal and a male condom, the best potential effectiveness for typical use is (0.92*0.86=) 0.79.

However, the major take-away (at least for me) is the worlds of difference seen in the comparison between the effective pregnancy rates shown in the first two rows when compared with the third row. It’s like night and day. If one of the partners is using a method from the third row, the improvements provided from the use of any of the methods shown in the first two rows is effectively negligible. For example, if we look at combining male condom use (0.86) with female sterilization (0.05), and assume that these two method were totally independent (which is – in my opinion – a safe assumption in this case), then the resulting chance of pregnancy over 10 years of using this combination of birth control measures is (0.86*0.05=) 0.04; a change of 0.01.

The only way to see a significant improvement within this bottom row is if they were combined with another method from the third row. In the case of combining male sterilization (0.02) and female sterilization (0.05), the resulting chance of pregnancy over 10 years would be 0.001 or a 50-fold increase over female sterilization alone.

Of course, the statistics presented in the article are rates garnered at a population level. Like so many things in life, when one looks at individual cases, the picture can appear quite different. After all, in order to get that number of “5 in 100 over 10 years” for female sterilization, there had to be some women who got sterilized and also got pregnant. Part of this is due to potential errors in the medical procedure or with the medical device. Part of this is due to individual physiology. But while one can’t really change the impacts of either of these two factors, there is one other factor that alters an individual’s chance of getting pregnant: their copulation rate.

If a person's copulation rate is really high, it will have a major effect on the possibility of that particular individual getting pregnant, even if the effectiveness of their birth control method doesn't change. Why? Well, let's assume we are looking at a woman who has been sterilized (0.05). If this woman has sex only one time without any additional birth control, that chance 0.05. If that woman has sex once every single day for 10 years, then each time she has sex, there is an additive 5-in-100-over-10-years' chance that she will get pregnant. (Why is it additive and not multiplicative here? It’s for the same reason that there is a 1/6+1/6=1/3 chance of rolling at least one 6 when you roll two dice.) Of course, the chance of a resulting pregnancy (in the case of female sterilization - as with all of the cases on the bottom row) remains vanishingly small, due to the effectiveness of the form of birth control, but - given enough sexual encounters - the rate of 5-in-100-over-10-years does imply that a pregnancy will occur. And indeed, it does happen:
[A] mother from Menden, North Rhine-Westphalia, decided to have the sterilization after the birth of her second child in 2006. ... But in 2008 she became pregnant again and gave birth in 2009.
The truth is that having a copulation rate of zero (i.e., never having sex at all) is the best preventative to getting pregnant. (Keep in mind that this also means that you don't try to get in vitro fertilization, either.) Indeed, this course of "abstinence only" pregnancy control is often the method preferred by religious organizations (at least in the United Stated). Of course, what with humans being the biological animals that we are, copulation (and resulting pregnancy) tends to happen, even to men and women sworn to clerical celibacy.

Thursday, February 05, 2015

The Terrifyingly Simple Normalcy that Segregation Used to Be

I saw the following photo from a friend's Facebook newsroll:

What read while scolling through Facebook was "COLORADO ENTRANCE," and it was the incongruity of that statement (that there was an entrance specifically for people from Colorado) that made me stop at the photo and actually read it; to see that it was a color photo from the segregated South.

This made me wonder whether the fact that I unconsciously read "Colorado" instead of "colored" was an indication of the complete unthinkability that such institutionalized racism could exist made my unconscious mind immediately fill in the word as the name of the 38th State. The completely calm and completely normal-looking appearance of everything in the photo also is so foreign to me. Indeed, the utter banality of the form that segregation took in day-to-day life in the South reminded me of the phrase, "the banality of evil," first coined by Hannah Arendt. Here is a really good and easy to understand summary of Arendt's point about evil and how it is so often so banal:

The banality of evil (the subtitle of Arendt's book covering the war crimes trial in Jerusalem of Eichmann) derives from encountering Eichmann, a man conceived as being a characteristic monster, and discovering that he was an utterly normal type of man who produced evil as a matter of just doing his job, and not because he was some sort of monster. Extending this recognition to the broader populace, Arendt writes with some understanding as to why societies - filled with similarly innocuous (and even generally good) people - can cause such massive evil to take place:
The trouble with Eichmann was precisely that so many were like him. They were neither overly perverted nor sadistic. They were, and still are, terribly and terrifyingly normal... This normality was much more terrifying than all the atrocities put together...
-- Hannah Arendt, Eichmann in Jerusalem: Report of the Banality of Evil, pg. 276

This links back to what I find (and likely many find) so jarring about the photo above: its terrible and terrifying normality. It is the utter normality of the scene pictured above that is jarring. It is the dull, day-to-day reality of segregation that is worrisome. We so often learn about the harsh problems associated with Segregation - the lynchings, the beatings, the stacked juries - and we so often read about the Civil Rights movements - the marches, the sit-ins, the use of the National guard to open schools and universities to desegregation - that the picture of Segregation and the reaction to it seem so much more about action and reaction; of mostrous evil and righteous struggle. And it is easy to paint that picture. And it is easy to think in those terms. (Which makes it easier to paint the picture, and so on.) But, as the photo tacitly implies, for the vast amount of time and for the vast amount of people, Segregation was simply a boringly normal part of life.

Thinking on this, statements by some older Southern Whites who have their perspectives on life during Segregation ring even more sinister, despite their statements lacking any overt inflammatory statements about how they reveled in its more obviously monstrous aspects. One telling example is in the remembrances of former Mississippi governor, Haley Barbour, who commented that his town of Yazoo, MS, during the Civil Rights era, "wasn't that bad." In Salon, Steve Kornacki wrote about why Barbour's position on race in the South was troubling in a way that Clinton's wasn't:
The controversy that his remarks will surely stir ... underscores how problematic Barbour's political roots are for him. The simple fact that he was born in a segregated town ... isn't the issue. Bill Clinton was a product of segregation, don't forget. The problem is that Barbor, unlike Clinton, has never seemed to come to terms with what segregation meant to African-Americans throughotu the South - and what the legacy of segregation continues to mean now.
...[Barbour] has previously asserted that the integration of the University of Mississippi in 1962 - accomplished only through federal intervention and which set off riots that killed two people - was "a very pleasant experience."
He's also told of building a friendship ... at Ole Miss in 1965 with one of the school's few black students, a woman he identified ... as Verna Lee Bailey. ...Of course, the woman's real name is Verna Ann Bailey, and ... she didn't even recall meeting Barbour. She also remembered the integration of Ole Miss a little differently: "I thought my life was goign to end."
And then theres his claim that the South's wholesale transformation from Democratic to Republican stronghold had nothing to do with race.... That would be news to anyone familiar with the vote that Barry Goldwater received in Mississippi in the 1964 presidential election: 87 percent.... The truth, of course, is that the passage of Civil Rights in 1964 kicked off a steady, decades-long shift among white Southerners from the Democratic Party (which they'd been loyal to since northern Republicans had tried to impose the "humiliation" of Reconstruction on them) to the GOP.
It is hard to look back in history and not want to align yourself with the "bad guys." It is especially hard when the history you perceived was actually not that bad. In their paper, "But I'm no Bigot," authors O'Brien, Crandall, Horstman-Reser, and Warner discuss distancing strategies used by White Southerners to somehow say that they aren't racist (despite having racist attitudes). One major way was to define being racist as belonging to an openly racist and historically violently racist organization, such as the KKK, or doing outrageously racist things, such as Black lynching or cross burnings. However, as the photograph above shows, these sorts of actions wasn't what Segregation was about for most of the people most of the time. No, it was something far more troubling and worrisome, specifically for its non-overtness; it was something that was terrifying in retrospect because it was so normal as to not warrant much mention: it was the banality that everyday life with Segregation meant to the vast majority of people, Black and White.

And it was a form of racism that the vast majority of Whites supported, even as they might similarly have distanced themselves from the more overtly "evils" of Segregation (such as membership in the Klan or participation in lynchings).

And so we return to the photo of a covered entrance on which a sign marked "colored entrance" points, in shining neon lights, to an open door, outside of which stand a nicely attired woman in robin's-egg blue and girl in white with a bow in her hair. The woman appears to be putting something away in her purse while the girl waits; that somewhat bored stare that children have (while waiting, waiting, waiting for adults to do thier thing) marks her face. In the distance, a woman in a red dress walks up the street. A black-painted car shows up as as slightly blurred on the street, caught in motion as it drives down and to the right of the photo. Neon lights up the street point to other businesses, which - perhaps - also have similar signs attached to them: "colored entrance" or "White entrance." The woman in blue and girl with the bow in her hair, both standing outside the open door marked "colored entrance" are. The woman in red, walking away from the "colored entrance" is not.

... and the image, in its utter normalcy, forces the mind to think in those terms; those terms that were so normal then and so alien now; those terms that implicitly equated race with levels of purity and cleanliness. I would so much more like to change the sign to read as my unconscious initially read it: "COLORADO," but that is not what it says, and that is not was it - and the whole system of systematized and banalized malevalence that also spawned the KKK, cross burnings, church bombings, and (now) decades of post-desegregation White Southern butthurt - want us to think, in simple terms of "white" and "colored."

And so I go back and read "COLORED ENTRANCE," and I see one of the many simple, everyday evils that was Segregation. Seeing this Black woman and girl calmly and normally going about their business, I am reminded of the implicit hypocrisy and privilege inherent in statements made by Barbour and other old Southern Whites. And I am reminded of another part of American history - my history, despite having no close Southern roots - to which the myth of "American Exceptionalism" provides a tempting exit, paved (as shown by Barbour) with white-washed history and denial of any social responsibility.