Cracked had a very nice article on logical fallacies -- that we all make as a matter of course. Also some good illustrations and suggestions. Aside from the fact that it was a humor magazine that had such a nice article on rational thought, I was struck by the fact that each of the points mentioned are ones that the practice of science has addressed.
The 5 natural fallacies mentioned are:
5. We're Not Programmed to Seek "Truth," We're Programmed to "Win"
4. Our Brains Don't Understand Probability
3. We Think Everyone's Out to Get Us
2. We're Hard-Wired to Have a Double Standard
1. Facts Don't Change Our Minds
Let's take a look at what science method does to combat these:
09 July 2012
07 July 2012
In the weekend heat
Sometimes it's easy to take the weather personally. Yesterday, DC set its record for consecutive days 95 F or above (35 C), with 9, and will likely obliterate it by going to 11 straight days, adding in today and tomorrow. The record it breaks, 8, was first set in 1987 -- the first summer I was here. It was tied twice more, first in 1993 -- my third summer. At the time, the summer of 1987 set many of the all-time records for sustained heat. Probably several of the summers since then would have as well, if 1987 hadn't beat them to the punch. Rephrase: many of the past 25 years would have set sustained heat records if compared only to the observations from 1880-1980. What used to be unheard of is now 'normal', or at least common. I'll be pulling down the data once NCDC is working again.
In the midst of the heat, well, we're hot here, and thunderstorms, I'll remind folks of the fact that you shouldn't run in thunderstorms. That also applies to biking and walking and other outdoor activities. If it's only heat you're dealing with, remember to drink enough fluids. And, one trick for keeping cool while exercising is to dump some cool/cold water on your head. Preferably to get a hat wet (it soaks up more water than my ever-thinning hair). For more extreme cases, some ice cubes under your hat.
While my power came back after about 20 hours, friends didn't regain it until Tuesday (~90 hours) or Thursday (~140 hours). Again, this is for wealthy, and densely populated, areas of a wealthy country. West Virginia has not been faring as 'well'. See this also. Noticed in passing (unfortunately I don't remember exact source, quite possibly a Capital Weather Gang tweet*) was that US average was 214 minutes of power failure per year. Unfortunately, even the better parts of this area are likely far in excess of that. Certainly my 20 hours this time are not balanced off with 6 previous years of 0. In other wealthy countries, it's order 20 minutes per year. In other words, US average is 10 times worse than other countries, and the Capitol area is closer to 100 times. This is not the first time we've lost power this year, and won't be the last.
* My apologies to the original source if it wasn't this. In any case, Capital Weather Gang is well worth reading, and has a blog as well.
At the same time as we were obliterating our record for sustained extreme heat, a friend bragged that Phoenix, Arizona, had its coldest 4th of July in 100 years -- 76 F (25 C). We were 20 F hotter. A different friend commented that he'd escaped the DC heat by going to the Bahamas. Summer in the Caribbean to escape the heat ...
In the midst of the heat, well, we're hot here, and thunderstorms, I'll remind folks of the fact that you shouldn't run in thunderstorms. That also applies to biking and walking and other outdoor activities. If it's only heat you're dealing with, remember to drink enough fluids. And, one trick for keeping cool while exercising is to dump some cool/cold water on your head. Preferably to get a hat wet (it soaks up more water than my ever-thinning hair). For more extreme cases, some ice cubes under your hat.
While my power came back after about 20 hours, friends didn't regain it until Tuesday (~90 hours) or Thursday (~140 hours). Again, this is for wealthy, and densely populated, areas of a wealthy country. West Virginia has not been faring as 'well'. See this also. Noticed in passing (unfortunately I don't remember exact source, quite possibly a Capital Weather Gang tweet*) was that US average was 214 minutes of power failure per year. Unfortunately, even the better parts of this area are likely far in excess of that. Certainly my 20 hours this time are not balanced off with 6 previous years of 0. In other wealthy countries, it's order 20 minutes per year. In other words, US average is 10 times worse than other countries, and the Capitol area is closer to 100 times. This is not the first time we've lost power this year, and won't be the last.
* My apologies to the original source if it wasn't this. In any case, Capital Weather Gang is well worth reading, and has a blog as well.
At the same time as we were obliterating our record for sustained extreme heat, a friend bragged that Phoenix, Arizona, had its coldest 4th of July in 100 years -- 76 F (25 C). We were 20 F hotter. A different friend commented that he'd escaped the DC heat by going to the Bahamas. Summer in the Caribbean to escape the heat ...
06 July 2012
Century storms
"That's two straight years we've had a 'storm of the century'; those weather guys are idiots!" Not long after I moved to the Washington, DC area, this happened, and the quote is real. I'm not sure that the storms involved really were 'storm of the century' events -- events that if we had a long enough record, we'd see happen about 10 times per 1000 years -- but it's something to think of a little quantitatively, particularly in light of my normally abnormal note.
Let's suppose that we're building a house and would like it to last 30 years. Well, to be specific, let's say we'd like a 99% chance of it lasting that long. Obviously it has to be able to survive events that we'd expect to happen once per year. And we can probably ignore things that we'd expect only once in a million years. But what about a once in 100 year event? The name misleads us in to thinking that the next time such an event would happen is 100 years after the last time. While natural reading, it's wrong mathematics. We could easily be in the unlucky 30 years that sees a 100 year event. We could even see it twice. But is there less than a 1% chance of having one 100 year event in a span of 30 years? That's our design requirement. If it can be expected more often than that, our house design is not reliable enough. We need something better. And we'll need to get quantitative.
Let's suppose that we're building a house and would like it to last 30 years. Well, to be specific, let's say we'd like a 99% chance of it lasting that long. Obviously it has to be able to survive events that we'd expect to happen once per year. And we can probably ignore things that we'd expect only once in a million years. But what about a once in 100 year event? The name misleads us in to thinking that the next time such an event would happen is 100 years after the last time. While natural reading, it's wrong mathematics. We could easily be in the unlucky 30 years that sees a 100 year event. We could even see it twice. But is there less than a 1% chance of having one 100 year event in a span of 30 years? That's our design requirement. If it can be expected more often than that, our house design is not reliable enough. We need something better. And we'll need to get quantitative.
05 July 2012
Normally abnormal
Normal and abnormal are among those words that don't mean a lot without knowing the context; 'rapid', I avoid entirely having hung around with both nuclear physicists and astrophysicists, for whom rapid can mean a femtosecond, or 100 million years. It's normal to be hotter or colder than normal. It would be highly abnormal to always be right at normal. While perfectly good English, let's do some work to make this real for understanding weather and climate.
One sense of 'normal' we have is the average value. The average temperature for July 2nd in my area is, say, 86 F (30 C). This is a useful figure, at least in the sense that we then expect temperatures to be closer to that than, say, 50 C, or 10 C. But it would be highly abnormal -- something seldom seen -- for the temperature to be exactly 86 F for five consecutive July 2nds.
To take a comment of mine from Tuesday, we had about 1 hour of winds averaging 50 mph (22 m/s) in the recent storm. Such winds are highly abnormal, in that the average is 5-10 mph. But there are 8766 hours in a year. It is normal, I believe (haven't pulled down the full data set), for at least 1 hour in the year to average 50 mph here. One sense of normal is the arithmetic average. Another is 'what are the winds you see less than 1% of the time'? That would be the 99th percentile winds -- you get that or faster 87.66 hours per year. 99.9th percentile is 8.766 hours, which I think is about right for 50 mph in this area. 99.99th percentile is something you expect to see about 50 minutes each year (maybe this is where we were). In other words, it is normal to be that abnormal.
One sense of 'normal' we have is the average value. The average temperature for July 2nd in my area is, say, 86 F (30 C). This is a useful figure, at least in the sense that we then expect temperatures to be closer to that than, say, 50 C, or 10 C. But it would be highly abnormal -- something seldom seen -- for the temperature to be exactly 86 F for five consecutive July 2nds.
To take a comment of mine from Tuesday, we had about 1 hour of winds averaging 50 mph (22 m/s) in the recent storm. Such winds are highly abnormal, in that the average is 5-10 mph. But there are 8766 hours in a year. It is normal, I believe (haven't pulled down the full data set), for at least 1 hour in the year to average 50 mph here. One sense of normal is the arithmetic average. Another is 'what are the winds you see less than 1% of the time'? That would be the 99th percentile winds -- you get that or faster 87.66 hours per year. 99.9th percentile is 8.766 hours, which I think is about right for 50 mph in this area. 99.99th percentile is something you expect to see about 50 minutes each year (maybe this is where we were). In other words, it is normal to be that abnormal.
04 July 2012
Happy 4th of July
Hope everyone is having a happy 4th of July. For the USA readers, two sets of words in reminder:
1)
IN CONGRESS, July 4, 1776.
The unanimous Declaration of the thirteen united States of America,
When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.--That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, --That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness. Prudence, indeed, will dictate that Governments long established should not be changed for light and transient causes; and accordingly all experience hath shewn, that mankind are more disposed to suffer, while evils are sufferable, than to right themselves by abolishing the forms to which they are accustomed.
(et seq.)
2)
The Constitution of the United States
Preamble
We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.
Back to me:
Though today is the day officially designated for the first, I think the second is the more significant for what it is we are celebrating. The constitution is the basis on which we celebrate being a nation.
1)
IN CONGRESS, July 4, 1776.
The unanimous Declaration of the thirteen united States of America,
When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.--That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, --That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness. Prudence, indeed, will dictate that Governments long established should not be changed for light and transient causes; and accordingly all experience hath shewn, that mankind are more disposed to suffer, while evils are sufferable, than to right themselves by abolishing the forms to which they are accustomed.
(et seq.)
2)
The Constitution of the United States
Preamble
We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.
Back to me:
Though today is the day officially designated for the first, I think the second is the more significant for what it is we are celebrating. The constitution is the basis on which we celebrate being a nation.
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