Tuesday, June 30, 2009
Solara wind
I own a 2004 Toyota Solara coupe. I have been generally happy with the car but had not done much long distance driving. Recently I have noticed an annoying problem. When cruising at highway speeds there is sometimes intrusive wind noise. It sounds like the driver's window is slightly open. I think this is happening when there is a crosswind at the wrong angle. There doesn't seem to be a problem in still air. So car designers please test your creations at an angle in the wind tunnel as well as straight on.
Saturday, June 27, 2009
Petty Theft
I recently traveled to Baltimore . I stayed in a Holiday Inn. While reviewing the charges on my credit card I noted an unexpected charge for $3 which turned out to be for using a bottled water which had been left in the room. This is the sort of petty fee which expensive hotels are notorious for. I have doubts the profit is worth the ill will they generate.
Blogging will be sporadic for a while.
Blogging will be sporadic for a while.
Friday, June 26, 2009
Siding
My condo is part of a complex in which each building contains 4 or 6 two story units in a row. The buildings have wooden siding which periodically needs to be stained. As part of the process any bad siding boards are replaced. The top picture shows this process in October 2000. The second picture shows the same building currently. In both cases the white boards are siding that has just been replaced. As can be seen the siding does not seem to be very durable which increases the maintenance expense. Part of my complex (and all of a neighboring complex) got tired of this and replaced all the wooden siding with vinyl. This is expensive but might be worth it in the long run if it reduces upkeep.
Thursday, June 25, 2009
Taken Polygraph
Tuesday afternoon I drove down to Baltimore for the polygraph test required for my security clearance. The drive took about 4 hours with only minor traffic delays. A reservation had been made for me in a hotel near the facility which does the exams.
The exam itself was scheduled for 11:30 Wednesday. You aren't told immediately if you have passed. However the exam appeared to go smoothly and only lasted about 90 minutes which I gather is a good sign.
I have some doubts about effectiveness. I won't detail my reasons as this might help someone beat the exam which I have no particular interest in doing. And the process does have a certain sobering effect as it emphasizes that the government takes security very seriously. Something to consider before accepting any job offers which may be forthcoming.
The drive back took a bit longer as I stopped once for food and gas and also ran into some traffic delays. Still I was back by 7pm.
The exam itself was scheduled for 11:30 Wednesday. You aren't told immediately if you have passed. However the exam appeared to go smoothly and only lasted about 90 minutes which I gather is a good sign.
I have some doubts about effectiveness. I won't detail my reasons as this might help someone beat the exam which I have no particular interest in doing. And the process does have a certain sobering effect as it emphasizes that the government takes security very seriously. Something to consider before accepting any job offers which may be forthcoming.
The drive back took a bit longer as I stopped once for food and gas and also ran into some traffic delays. Still I was back by 7pm.
Wednesday, June 24, 2009
Killer trains
In the course of defending the safety record of trains in light of the recent DC Metro fatal accident Matthew Yglesias gets carried away and states:
... On a typical day, of course, the United States has zero train-related fatalities.
This is not true because it does not take into account people hit by trains, a common omission when people talk about how safe trains are. According to this in 2008 there were 716 fatal incidents (killing 794 people) involving trains. In just one of these were passengers (24) killed. Trains are very safe for passengers. They are less safe overall.
... On a typical day, of course, the United States has zero train-related fatalities.
This is not true because it does not take into account people hit by trains, a common omission when people talk about how safe trains are. According to this in 2008 there were 716 fatal incidents (killing 794 people) involving trains. In just one of these were passengers (24) killed. Trains are very safe for passengers. They are less safe overall.
Tuesday, June 23, 2009
Lake Peekskill
The streets around Lake Peekskill are a bit confusing. I got lost a couple of times on Sunday driving to an address I had been to before. Hopefully driving to Baltimore will be less complicated.
Monday, June 22, 2009
Thrillers
I recently read "Scarecrow", "Wicked Prey" and "Road Dogs" the latest books by thriller writers Michael Connelly , John Sandford and Elmore Leonard respectively. All three writers are prolific and I have enjoyed many of their past books. I would rank Sandford first, Leonard second and Connolly third with their latest books in the same order. I wouldn't claim these books are great literature but if you enjoy entertaining stories about cops and criminals these authors are worth a try.
Sunday, June 21, 2009
Sleeping Beauty problem
I encountered the Sleeping Beauty problem in comments on another blog. The following formulation is copied from the wikipedia link. I basically agree with the wikipedia analysis. You may want to think about the problem before following the link.
The paradox imagines that Sleeping Beauty volunteers to undergo the following experiment. On Sunday she is given a drug that sends her to sleep. A fair coin is then tossed just once in the course of the experiment to determine which experimental procedure is undertaken. If the coin comes up heads, Beauty is awakened and interviewed on Monday, and then the experiment ends. If the coin comes up tails, she is awakened and interviewed on Monday, given a second dose of the sleeping drug, and awakened and interviewed again on Tuesday. The experiment then ends on Tuesday, without flipping the coin again. The sleeping drug induces a mild amnesia, so that she cannot remember any previous awakenings during the course of the experiment (if any). During the experiment, she has no access to anything that would give a clue as to the day of the week. However, she knows all the details of the experiment.
Each interview consists of one question, "What is your credence [subjective probability] now for the proposition that our coin landed heads?"
The paradox imagines that Sleeping Beauty volunteers to undergo the following experiment. On Sunday she is given a drug that sends her to sleep. A fair coin is then tossed just once in the course of the experiment to determine which experimental procedure is undertaken. If the coin comes up heads, Beauty is awakened and interviewed on Monday, and then the experiment ends. If the coin comes up tails, she is awakened and interviewed on Monday, given a second dose of the sleeping drug, and awakened and interviewed again on Tuesday. The experiment then ends on Tuesday, without flipping the coin again. The sleeping drug induces a mild amnesia, so that she cannot remember any previous awakenings during the course of the experiment (if any). During the experiment, she has no access to anything that would give a clue as to the day of the week. However, she knows all the details of the experiment.
Each interview consists of one question, "What is your credence [subjective probability] now for the proposition that our coin landed heads?"
Saturday, June 20, 2009
Pending Polygraph
The polygraph test required for my security clearance has been scheduled. This will involve a trip to Baltimore. I have been told the test is just intended to verify information I have already provided. Since I have led a rather boring life hopefully things will go smoothly.
Dice puzzle
The following puzzle appeared (worded differently) in John Derbyshire's May diary .
Can you label the faces of 3 cubical dice with the numbers 1,2,3 ... 18 (using each number exactly once) so that if someone else picks any one of the three dice you can then pick another so that if you both roll your chosen dies with the high roller winning you will win more than half the time? How big an edge can you achieve by an appropriate labeling? Can you prove optimality?
Derbyshire follows up here .
Can you label the faces of 3 cubical dice with the numbers 1,2,3 ... 18 (using each number exactly once) so that if someone else picks any one of the three dice you can then pick another so that if you both roll your chosen dies with the high roller winning you will win more than half the time? How big an edge can you achieve by an appropriate labeling? Can you prove optimality?
Derbyshire follows up here .
Thursday, June 18, 2009
Getting a physical
I got a physical exam a couple of weeks ago and went in for a follow up Tuesday to discuss my lab test results. Fortunately everything was normal.
A recent news report on rising health insurance costs suggested increasing worry about losing coverage was encouraging more utilization contributing to cost increases.
Costs will rise in part because workers worried about losing their jobs are using their health care more while they still have it ...
This initially seemed plausible to me as I have been thinking I should get stuff done while I am still covered under Cobra. But reading further in the story:
The 9% increase predicted for 2010, however, represents a slight decrease from the 9.2% PWC projected for this year, and 9.9% predicted for 2008 ...
which causes me to doubt that increasing insecurity actually explains much. The 9% annual cost increases are alarming and obviously cannot continue indefinitely.
A recent news report on rising health insurance costs suggested increasing worry about losing coverage was encouraging more utilization contributing to cost increases.
Costs will rise in part because workers worried about losing their jobs are using their health care more while they still have it ...
This initially seemed plausible to me as I have been thinking I should get stuff done while I am still covered under Cobra. But reading further in the story:
The 9% increase predicted for 2010, however, represents a slight decrease from the 9.2% PWC projected for this year, and 9.9% predicted for 2008 ...
which causes me to doubt that increasing insecurity actually explains much. The 9% annual cost increases are alarming and obviously cannot continue indefinitely.
Wednesday, June 17, 2009
Gas pains
Gas prices have risen in recent weeks. They are now near $3/gallon around here a big rise from the $2/gallon low of last winter. This isn't really a big surprise to me. I suspect we are near (if not actually at) peak oil . Which means that, while there will continue to be fluctuations in the price of gas, the long term trend will be strongly upward. This of course will be bad for the economy, one of the reasons I am nervous about the economic future even after we are past the present crisis.
On the plus side, this would be good news on the climate change front. Some of the more pessimistic scenarios may be impossible because there just aren't enough fossil fuels readily available. See this via Stoat . Of course there are reasons to be cautious about basing reserve estimates on current technology.
On the plus side, this would be good news on the climate change front. Some of the more pessimistic scenarios may be impossible because there just aren't enough fossil fuels readily available. See this via Stoat . Of course there are reasons to be cautious about basing reserve estimates on current technology.
Tuesday, June 16, 2009
Tax shift
As a condominium owner, I was disturbed to read in my morning paper about a bill (A4588-A, S-1706-A) that will likely increase the share of property taxes paid by condominium and co-op owners in Westchester County. I see no good reason for altering the longstanding property tax status of condominiums and co-ops. The bill has passed the state assembly and is pending before the state senate. Hopefully the current deadlock in the state senate will prevent passage.
It was particularly annoying to read that my state assembly representative, Sandra R. Galef (90th district), was a cosponsor of the bill in the assembly and my state senator, Suzi Oppenheimer (37th district), is the main sponsor of the bill in the state senate. Something I will remember come election day.
It was particularly annoying to read that my state assembly representative, Sandra R. Galef (90th district), was a cosponsor of the bill in the assembly and my state senator, Suzi Oppenheimer (37th district), is the main sponsor of the bill in the state senate. Something I will remember come election day.
Monday, June 15, 2009
Taxes again
I deposited the second portion of my New York State tax refund today. I got my refund in two parts because I made a copying error when filing my return. Luckily I actually came out $1.22 ahead because of New York State's refusal to concern itself with pennies. Not worth the extra hassle of course but preferable to losing $1.22.
This was also the due date for second quarter estimated taxes which I duly paid.
This was also the due date for second quarter estimated taxes which I duly paid.
Sunday, June 14, 2009
Long tail solution
Some time ago I posted a puzzle and promised a solution later. The solution appears below.
The problem concerns distributions with tails obeying a power law. This means values above some bound b the density of values x is proportional to 1/x**a for some value a. Let us compute the mean and median values of the tail.
The value of the mean is (integral(b to infinity)(x/x**a)dx)/(integral(b to infinity)(1/x**a)dx) = ((1-a)/(2-a))*b.
The value of the median is that value of c for which (integral(c to infinity)(1/x**a)dx) = .5*(integral(b to infinity)(1/x**a)dx) => c**(1-a) = .5*b**(1-a) => c=b*2**(1/(a-1)).
So the ratio of the mean to the median is (a-1)/((a-2)*2**(1/(a-1))).
For the given puzzle the mean is $75000 and the median is $22000. So the ratio is 72/22 = 3.40909... and we wish to find the value of a for which (a-1)/((a-2)*2**(1/(a-1))) equals this ratio.
A simple program finds a=2.196695263+. We are looking for b which will be ((a-2)/(a-1))*$75000 = $12327.40.
So the answers given in the comments were correct.
The problem concerns distributions with tails obeying a power law. This means values above some bound b the density of values x is proportional to 1/x**a for some value a. Let us compute the mean and median values of the tail.
The value of the mean is (integral(b to infinity)(x/x**a)dx)/(integral(b to infinity)(1/x**a)dx) = ((1-a)/(2-a))*b.
The value of the median is that value of c for which (integral(c to infinity)(1/x**a)dx) = .5*(integral(b to infinity)(1/x**a)dx) => c**(1-a) = .5*b**(1-a) => c=b*2**(1/(a-1)).
So the ratio of the mean to the median is (a-1)/((a-2)*2**(1/(a-1))).
For the given puzzle the mean is $75000 and the median is $22000. So the ratio is 72/22 = 3.40909... and we wish to find the value of a for which (a-1)/((a-2)*2**(1/(a-1))) equals this ratio.
A simple program finds a=2.196695263+. We are looking for b which will be ((a-2)/(a-1))*$75000 = $12327.40.
So the answers given in the comments were correct.
Saturday, June 13, 2009
North County Trailway
I took a walk today on the North County Trailway . The trail follows an abandoned railroad right away and goes on for many miles. The portion I like best lies between route 134 and route 118 and crosses the Croton Reservoir.
The trail goes under route 134 just before route 134 runs into route 100. You can park on the south shoulder of route 134 and walk down to the trail. Following the trail north it is about a mile to a bridge over the Croton Reservoir. The trail then soon crosses route 118 where there is a small parking area on the north side. I generally park on route 134 as it is closer to where I live and I like walking towards the bridge as a destination.
Summer weather around here can be hot and humid making walking a bit unpleasant. Today was ok, cloudy and humid but not too hot. The vegetation along the trail was notably lush and green. The trail is paved which is nice except that it attracts cyclists who can sometimes be annoying as they whiz past.
I took the picture in October 2000 looking east from the bridge over the Croton Reservoir. The bridge in the distance carries Route 100.
The trail goes under route 134 just before route 134 runs into route 100. You can park on the south shoulder of route 134 and walk down to the trail. Following the trail north it is about a mile to a bridge over the Croton Reservoir. The trail then soon crosses route 118 where there is a small parking area on the north side. I generally park on route 134 as it is closer to where I live and I like walking towards the bridge as a destination.
Summer weather around here can be hot and humid making walking a bit unpleasant. Today was ok, cloudy and humid but not too hot. The vegetation along the trail was notably lush and green. The trail is paved which is nice except that it attracts cyclists who can sometimes be annoying as they whiz past.
I took the picture in October 2000 looking east from the bridge over the Croton Reservoir. The bridge in the distance carries Route 100.
Friday, June 12, 2009
Middle East options
One Middle East problem is that the Palestinian residents of the Gaza strip and the West Bank are stateless, they are citizens of no state. Stateless people often find themselves badly treated and the Palestinians are no exception. There are several ways for the Palestinians to become citizens of a state:
1) They could become citizens of Israel.
2) They could become citizens of an independent state (or states).
3) They could become citizens of existing states other than Israel (most plausibly Egypt and Jordan).
Matthew Yglesias doesn't like option 3.
... total non-starter.
While the problems Yglesias points out are real, the other options have problems as well. Yglesias favors option 2 but it is doubtful that an independent Palestinian state would be viable. Among other problems it would likely be too weak to defend itself against Israeli aggression whether military or economic. Egypt and Jordan are also weaker than Israel but they have more ability to resist and thereby deter gratuitous aggression.
I think it is possible that option 3 is the lesser evil.
1) They could become citizens of Israel.
2) They could become citizens of an independent state (or states).
3) They could become citizens of existing states other than Israel (most plausibly Egypt and Jordan).
Matthew Yglesias doesn't like option 3.
... total non-starter.
While the problems Yglesias points out are real, the other options have problems as well. Yglesias favors option 2 but it is doubtful that an independent Palestinian state would be viable. Among other problems it would likely be too weak to defend itself against Israeli aggression whether military or economic. Egypt and Jordan are also weaker than Israel but they have more ability to resist and thereby deter gratuitous aggression.
I think it is possible that option 3 is the lesser evil.
Thursday, June 11, 2009
Unemployment computation
I have been collecting unemployment insurance since being laid off a few months ago. A couple of weeks ago I attended the Yale commencement which meant I wasn't available for employment on that Monday as I duly reported when certifying for that week. I was unsure how this would affect my benefit amount. It turns out my state benefit was reduced by 25% but the federal $25 per week supplement was unaffected.
Wednesday, June 10, 2009
Linked in
Part of my separation package with my former employer was the services of an outplacement firm. This firm suggested the Linked in social networking site was useful for job hunting. So about 6 weeks ago I registered with the site and set up a basic profile but didn't do anything further. Today I attended a class at the outplacement firm on Linked in basics. Perhaps this will motivate me to start using the site.
Tuesday, June 9, 2009
Risky business
Holman Jenkins has an essay on the financial crisis which has prompted some comment among blogs. Felix Salmon criticizes it here and here .
My take is the essay is peculiar in that it seems to boil down to "s**t happens". This is true but it does not mean what happened was just bad luck and nobody's fault. It is not the job of Wall Street to simply assume risk, it is Wall Street's job to price risk and only assume risk when adequately compensated. It is now clear that Wall Street failed (through some combination of greed and stupidity) to assess risk competently. This needs to be fixed. Jenkins does not acknowledge this.
My take is the essay is peculiar in that it seems to boil down to "s**t happens". This is true but it does not mean what happened was just bad luck and nobody's fault. It is not the job of Wall Street to simply assume risk, it is Wall Street's job to price risk and only assume risk when adequately compensated. It is now clear that Wall Street failed (through some combination of greed and stupidity) to assess risk competently. This needs to be fixed. Jenkins does not acknowledge this.
The law of large numbers
Ezra Klein points to this paper (400k pdf file) by Tyler Cowen.
Cowen claims that
... In favored approaches of the 1980s and 1990s, it was common to admit that individual mistakes were possible but that such mistakes would be governed by the “law of large numbers.” ...
with the implication that this meant in the aggregate mistakes would cancel out. This shows a rather serious misunderstanding of the law of large numbers.
Basically the law of large numbers says that under some conditions independent random errors will tend to cancel out. But it is incorrect to expect it to apply to errors made by investors because such errors are not independent in general. For example if the government makes a mistake in computing some economic statistic many investors may make similar errors because they rely on this statistic. Similarly for any other widely circulated error. Additionally because of the human tendency to go along with the crowd, late deciders will tend to adopt the opinions of early deciders another source of dependence.
Modern economics is often criticized for relying on unrealistic models of economic behavior which don't apply to the real economy. I don't know if Cowen has correctly described rational expectations models. If he has, they appear to be seriously flawed.
Cowen claims that
... In favored approaches of the 1980s and 1990s, it was common to admit that individual mistakes were possible but that such mistakes would be governed by the “law of large numbers.” ...
with the implication that this meant in the aggregate mistakes would cancel out. This shows a rather serious misunderstanding of the law of large numbers.
Basically the law of large numbers says that under some conditions independent random errors will tend to cancel out. But it is incorrect to expect it to apply to errors made by investors because such errors are not independent in general. For example if the government makes a mistake in computing some economic statistic many investors may make similar errors because they rely on this statistic. Similarly for any other widely circulated error. Additionally because of the human tendency to go along with the crowd, late deciders will tend to adopt the opinions of early deciders another source of dependence.
Modern economics is often criticized for relying on unrealistic models of economic behavior which don't apply to the real economy. I don't know if Cowen has correctly described rational expectations models. If he has, they appear to be seriously flawed.
Sunday, June 7, 2009
Outing
Recently Ed Whalen revealed the true identity of the blogger known as Publius . This has generated a certain amount of comment . My take is that while I can think of several good (or at least defensible) reasons for such actions, spite (which seems to be the primary motivation here) isn't one of them.
Saturday, June 6, 2009
Advertising
James Fallows passes on a reader's theory that advertising revenues are plunging because advertisers have figured out that advertising doesn't work. This makes no sense to me. Advertisers are not moving ads from newspapers to Craigslist because advertising doesn't work, they are moving ads because Craigslist is a better way of distributing ads. Newspapers are in trouble because the internet has made physically printing and distributing a newspaper increasingly cost ineffective. Advertising will change but there will always be a need for ways for people with things to sell to communicate with potential buyers.
Friday, June 5, 2009
Good vrs Great
In my view an instance of some repeated experience (like eating or sex) can be below average and still be perceived as good but being below average and being great are incompatible. So for example going often to a fancy restaurant and expecting a great meal every time (or even most times) is unrealistic. Better to aim for a good meal almost every time and an occasional great meal. This is also a reason (which I might heed more) for trying new things which you have not yet become blase about.
Thursday, June 4, 2009
New dishwasher
As noted here my dishwasher recently died. Exhibiting somewhat atypical decisiveness I used the August 2008 Consumer Reports to select a Whirlpool DU1055XTV to replace it. Whirlpool claims this model is similar to the DU1055XTS which Consumer Reports rated a best buy. I bought the replacement from Sears and it was delivered and installed yesterday. It took 2 people about 40 minutes to install it. Installation didn't look all that complicated since it was replacing an existing dishwasher. Still probably a bit beyond my handyman skills. And by some bizarre quirk in New York state tax law paying for installation made the whole purchase exempt from sales tax.
Initial reports are the new dishwasher compares favorably to the old in cleaning ability. Possibly the old dishwasher hadn't been working too well even before failing completely.
Initial reports are the new dishwasher compares favorably to the old in cleaning ability. Possibly the old dishwasher hadn't been working too well even before failing completely.
Wednesday, June 3, 2009
Film dying
For many years I took film to the A&P in Millwood to be developed. A service picked up film and returned prints. Then I got a digital camera for Christmas 2007 and stopped using my film camera. Apparently a common story as I was in the A&P for other reasons today and noticed they no longer offer film development. As I recall the last time I dropped off film the service was no longer picking up daily, a sign of dropping volume. Apparently it eventually became unprofitable all together.
I like my new digital camera a lot but it is a little sad to reflect on all the people and businesses that lost out as film became obsolete.
The photo is of me, taken in September 2007, and may be the last photo my film camera will take.
Tuesday, June 2, 2009
Abortion and murder
There are many things in dispute regarding abortion. However one thing that should not be in dispute (at least in my view) is the question of whether abortion is murder. It clearly is not. Murder is a legal term for certain unlawful killings. As long as abortion remains legal it is not murder.
Monday, June 1, 2009
Car trouble
So GM joins Chrysler in bankruptcy . It is hard for me to be too concerned about their fate because not only have I never owned a GM or Chrysler car I don't remember for sure ever driving one. There has been a lot written about the decline of the domestic auto makers but the issue of brand images seems a bit neglected. Somehow for me (and I suspect many) the domestic brands became cars for low class stupid people. No doubt this is unfair but lots of marketing does not work on any sort of rational level. Obviously whatever their other problems it is hard to succeed with that sort of brand image. And I don't see government ownership helping much.
I have owned and rented Ford cars and perhaps as a result am less biased against Ford than GM or Chrysler. Still I didn't look at Fords when I was in the market last year. And it is difficult to compete against massive government subsidies. It is hard to see things working out well for any of the big three.
I have owned and rented Ford cars and perhaps as a result am less biased against Ford than GM or Chrysler. Still I didn't look at Fords when I was in the market last year. And it is difficult to compete against massive government subsidies. It is hard to see things working out well for any of the big three.
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