Thursday, December 27, 2012

Travelling to another dot

(The world did not end on 21st December as widely expected so you are condemned to read more of my posts. My commiserations. But don't lose hope.)

In the Wodehouse novel 'Mike and Psmith', while  explaining the benefits of not getting up early in the morning, Psmith tells Mike:
"One of the Georges," said Psmith, "I forget which, once said that a certain number of hours' sleep a day - I cannot recall for the moment how many - made a man something, which for the time being  has slipped my memory. However, there you are. I've given you the main idea of the thing.
I find myself in the Psmith situation. I had read an article (I don't think it was by a George but then, it could have been one.) which had been about some people who had lived for some days (or weeks or months) in isolation, having no contact with the rest of the world during that period, and the psychological problems this produced. There you are. I've given you the main idea of the thing. I was reminded of this article when I read Packing for Mars: The Curious Science of Life in the Void by Mary Roach which is about the technological, political and psychological challenges involved in sending a manned mission to Mars. Mary Roach writes:
To the rocket scientist, you are a problem.  You are the most irritating piece of machinery he or she will ever have to deal with. You and your fluctuating metabolism, your puny memory, your frame that comes in a million different configurations. You are unpredictable. You're inconstant. You take weeks to fix.  The engineer must worry about the water and oxygen and food you'll need in space, about how much extra fuel it will take to launch your shrimp cocktail and irradiated beef tacos.  A solar cell or a thruster nozzle is stable and undemanding. It does not excrete or panic or fall in love with the mission commander. It has no ego.  Its structural elements don't start to break down without gravity, and it works just fine without sleep.
People have been fascinated by Mars (including Mohammad Ali) for a long time but space travel is not the fun adventure that it is portrayed as in PR videos. There are plans to send 80,000 people to Mars but that is easier said than done. Apart from the various psychological problems, you have to deal with things like motion sickness, vomiting in helmets, excess gravity, low gravity, worry about the impact tolerance of the human body, deal with body odour and how to carry out many mundane activities.

Food for space has to be light and compact - every extra pound costs thousands of dollars to launch. It should not be crumbly because in anti-gravity, crumbs clog the controls or may get into some one's eyes. Astronauts have to drink recycled urine. They have to be specially toilet trained. If not careful, faeces may float around the spacecraft which is not a pleasant experience.Even the simple act of urination can, in the absence of gravity, become a medical emergency. And then there is religion:
Religious observations are even tougher in a real spacecraft.  Launch weight limitations forced Buzz Aldrin to pack a "tiny Host" and thimble-sized wine chalice for his DIY Communion on the moon.  Zero gravity and a ninety minute orbital day created so many questions for Muslim astronauts that a "Guideline of Performing Ibadah at the International Space Station" was drafted. Rather than require Muslim astronauts to pray five times during each ninety minute orbit of Earth, the guidelines allowed them to go by the twenty-four-hour cycle of the launch location.  Wipes ("not less than 3 pieces") could be used for preprayer cleansing. And since the orbiting Muslim who began his prayer while facing Mecca was likely, by prayer's end, to be mooning Mecca, provisions were made allowing him to simply face the Earth or "wherever." Lastly, instead of lowering the face to the ground, a trying manoeuvre in zero gravity, prostrating oneself could be approximated by "bringing down the chin closer to the knee," "using the eye lid as an indicator of the changing of posture" or - in the vein of "wherever" - simply "imagining" the sequence of movements.
The most interesting part of the book for me was a chapter describing an experiment where NASA observes volunteers who were asked to spend 3 months 24*7 lying on a bed. This was because during a trip to Mars, astronauts would have to spend about 6 months in a cramped space without much movement. For a couple of years after my stroke, I used to lie most of the time on the bed watching TV. I was aware that prolonged periods of inactivity causes some deterioration in bones and muscles but I didn't know that it could be so bad.

In 2 years, a paraplegic person could lose 1/3 to 1/2 the bone mass in the lower limbs,about the same amount that an astronaut could expect to lose on a 2 year mission to Mars. There is a very real danger that the bones of the astronaut may snap on returning to Earth's gravity. The best method for preventing bone loss is weight bearing exercise. In spite of the various ideas that have been tried over the years for dealing with bone and muscle loss, the best methods remain those that were available 40 years ago.

In spite of the perils, some astronauts are willing to go on a one-way trip to Mars with no possibility of return.These folks have incredible guts. The very thought of living in a cramped space for months on end far away from the earth gives me the heebie jeebies. (Does it have something to do with the DRD4-7R gene?) There have been suggestions of trying to see if humans can hibernate (like the folks of 'B'Ark) but the idea has never been pursued seriously because of ethical issues.

Finally, should so much resources be spent on sending a manned mission to Mars? Many reasons have been given in favour of space exploration. Neil deGrasse Tyson puts costs in perspective. As Mary Roach says:
The nobility of the human spirit grows harder for me to believe in.  War, zealotry, greed, malls, narcissism.  I see a backhanded nobility in excessive, impractical outlays of cash prompted by nothing loftier than a species joining hands and saying "I bet we can do this. "Yes, the money could be better spent on Earth.  But would it? Since when has money saved by government red-lining been spent on education and cancer research? It is always squandered.  Let's squander some on Mars.  Let's go out and play. 
Here is Mary Roach talking about her book at Google.

PS: A documentary on the case for Mars.

PPS: Bizarre space cases

Monday, December 17, 2012

The dark side of superstition

This is about a time about an year after my stroke. At that time I used to lie on the bed most of the day watching T.V.  I was not reading any books and there was no computer at home.I had no idea what I could do. I was thinking more along the lines of an Amitabh Bachchan quip in this song - 'Arre yeh jeena bhi koi jeena hai, lallu?' (This is immediately followed by one of my favourite songs which conveys a very different mood.)

There is a Malayalam movie on Asianet every afternoon which  I used to keep.This was not because I was particularly keen on watching it but I knew that the nurse would be interested in watching it. This would keep her awake so I would not have to strain too much to call her if I wanted to pass urine. Cunning devil, no?

One afternoon there was a movie starring the Malayalam super star Mammooty. I was not paying much attention to the movie initially. After some time I started becoming interested in the plot and started watching more earnestly. The story was as follows:

The Mammooty character (let us call him Kumar) was a respected school teacher in a typical Kerala village. He lived a normal life in a joint family and had a wife and 2 kids. The family had some hereditary disease like Huntington's Chorea. The family belief was that some goddess had put a curse on them which meant that 1 member of the family in every generation will go mad.

In this generation, it was the turn of an elderly uncle to go mad. He was kept in chains in a separate room. One day he suddenly died. After the cremation, the family waited and wondered who the goddess would choose as her next victim.

One night, Kumar had a bad dream and screamed in his sleep. Everyone rushed to his room to find out what the matter was. He assured them that he just had a bad dream and he was all right. Everyone looked at him suspiciously. They suspected that he had been chosen by the goddess to go mad. By the next morning the news had spread through the grapevine to the whole village. Kumar was blissfully unaware of all these developments as he made his way to the school the next day.

He was puzzled when the owner of a tea-stall where he used to stop regularly seemed to be in a hurry to get rid of him. The people he used to regularly chat with seemed to be keen to avoid him. In school, the students passed mocking remarks which he could not understand and his colleagues were avoiding eye contact. This strange behaviour went on for some days and Kumar began to suspect what the problem was.

His father-in-law heard the stories, decided that he cannot let his daughter and grand kids stay with a mad man and took them away in spite of his protests that there was nothing wrong with him. This broke him completely and he stopped caring about anything. He stopped talking to anybody and just stared silently when anybody asked him anything. He looked dishevelled and roamed around like a zombie. Eventually, he was kept in chains in a separate room like the uncle who had died. After many days, his mother took pity on him, mixed poison in his food and killed him.

I could picture myself in the shoes  of the Mammooty character. Jaya has been an indefatigable gatekeeper keeping out many superstitious beliefs which she knows irritates me, as also the suggestions of those who read nothing but know everything. I live among liberal believers and my heretical views don't provoke the kind of ostracizing seen in the Bible belt of the US. Jaya has also been able to ignore the various emotional blackmails that came her way.

I kept a watch out for the movie in various channels because I wanted to check if I remembered the facts right before writing this post but I never saw the movie again. I still don't know its title.

PS: It is not just about superstitions, it could be about something as simple as signing a piece of paper. Once, an Ayurvedic doctor gave some powder and said that a little bit of it should be mixed with milk and given to me everyday. He said that it contained silver and proceeded to extoll the virtues of silver as a curative agent for various neurological problems. Jaya asked him to write the prescription on his letterhead with his signature on it. He brushed this off as unimportant so his suggestion was ignored.

Sunday, December 9, 2012

What they conceal is vital - II

In this list of Carl Sagan quotes, I saw the following quote:
"I'm often asked the question, "Do you think there is extraterrestrial intelligence?" I give the standard arguments -- there are a lot of places out there, and use the word *billions*, and so on. And then I say it would be astonishing to me if there weren't extraterrestrial intelligence, but of course there is as yet no compelling evidence for it. And then I'm asked, "Yeah, but what do you really think?" I say, "I just told you what I really think." "Yeah, but what's your gut feeling?" But I try not to think with my gut. Really, it's okay to reserve judgment until the evidence is in.
But people often rely on gut feel for making decisions. When news reports have a lot of numbers, eyes typically glaze over so people in power get away with saying anything.What Steven Pinker calls 'failure of statistical thinking' has made it difficult for Facts to survive. In this video, Daniel Kahneman distinguishes two types of thinking: System 1 and System 2.System 1 represents what we call intuition. It tirelessly provides us with quick impressions, intentions and feelings. System 2, on the other hand, represents reason, self-control and considered decision making.

System  1 is fast and does not require much effort. System 2 is slow and requires effort. We rely most of the time on System 1 for our regular activities and it does fine.Occasionally, this causes problems. There are times when some statistical thinking using System 2 would have been beneficial but we often skip it since it requires time and effort. Advertising, political, nationalistic and religious messages target System 1 which is why they are so effective.

Some years back, I had read a book called How to Lie with Statistics by  Darrell Huff, the most widely read statistics book in the history of the world.  You can read it online here, Written almost 60 years ago, it gives many ways in which people present statistics in order to favour their biases. He says that the book sounds like a how-to manual for crooks for which his justification is - "the crooks already know these tricks; honest men must learn them in self-defence." Some of the techniques that he discusses are:
  1. Using a sample with built-in bias. Examples are TV and Internet polls.
  2. Using any of mean, median or mode as the 'average' depending on which one best represents your bias. Since most people won't know the difference between them ,you will generally be safe. For example, to depict the average income of the inhabitants of a country, the median is more informative than the mean. There is a joke that when Bill Gates visits an old age home, all inhabitants are millionaires on average.
  3. Failing to mention some numbers like sample size, confidence intervals etc. This is especially a problem on TV  because the screen changes so fast that you don't have time to read everything and only the shape of the image stays  in your mind.
  4. Misleading graphs - An example
  5. Misleading  figures - An example.
  6. Comparing  wrong percentages - An example
  7. Correlation is not causation - An example
  8. Post hoc ergo propter hoc
  9. Using impressively precise figures - Saying that the monthly expenditure of an average family is Rs. 12436 sounds more authoritative than saying it is around Rs. 12,000.
  10. Beware of extrapolations.
Darrell Huff says that there are 5 questions that one must ask when one sees any statistic:
  1. Who Says So?
  2. How Does He Know?
  3. What's Missing?
  4. Did Somebody Change the Subject?
  5. Does It Make Sense? 
Whenever one political party levels an accusation against a member of  another party, the latter responds by saying something like, 'People will not believe such wild allegations. They know better.' Want to bet? Initial reports tend to persist and myths are remarkably easy to spread because we use System  1 much more than System 2. This makes us us more enamoured of superficial things as depicted in Chekhov's short story, The First-Class Passenger. This is a difficult trap to avoid.

PS: There are many examples of statical machinations dissected at Ben  Goldacre's blog.