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Critique of Citizen Sleuths Probability Calculation of DB Cooper’s Tie

The DB Cooper Case is notable for its lack of physical evidence. On the airplane, Cooper left behind some cigarette butts, two leftover parachutes, a glass he used and a black clip-on tie. The cigarettes were misplaced and are considered lost, there may or may not be DNA in evidence from them. Cooper’s fingerprints were likely collected from the airplane, as about 60 sets of fingerprints were recorded. The big piece of evidence was the tie. Recent testing done by Tom Kaye has uncovered evidence on the tie [found on Cooper’s seat] that gives the clearest profile yet of who Dan Cooper was before the heist. Since it can’t be known for sure if the tie was actually Coopers, Kay et al performed a probability analysis.

Here are the components of the CS team analysis: 1) Twenty passengers potentially leaving a tie on Cooper’s flight including Cooper. 2) Forgetting the tie on the plane = 15% (best estimate). 3) Leaving the tie on Coopers seat = 5% (best estimate). 4) Smoker = 44% (percentage of males who smoked in 1970). 5) Passengers wearing a black tie = 35% (best estimate). From these numbers, it is concluded there is a “98% probability” the tie belongs to Cooper.

There are a few areas where Kaye and his team might have gone wrong. Most glaringly is the fact, with the back door of the aircraft open and a man jumping off the airstairs while in flight, the cabin in the aircraft would have been very windy, making the odds a tie landed on Cooper’s seat much higher. To give a more conservative estimate, variable #3 should be adjusted upwards, perhaps to as high as 25%. This adjustment gives us an approximate 90% probability the tie belongs to Cooper. Still high enough to affirm Kaye’s later analysis of the particles on the tie, but it does not cross the “two sigma threshold” Carr concludes. It’s a minor point, but an important one.

DB Cooper Paper: Surviving the Jump

I spent the last few weeks researching and working on a paper showing the probability of DB Cooper surviving his jump based on WWII parachuting data. (I’ve been on a DB Cooper kick lately.) Here is the pdf file:

Final Cooper Update

And Google Docs.

Paper will be updated soon with more data that confirms initial findings. ….Paper now updated.

D.B. Cooper Conjecture: The Tena Bar Find

Anyone who has ever become obsessed with the D.B. Cooper hijacking is well aware of the Tena Bar find, when $5800 dollars in the ransom money was found by eight-year-old Brian Ingram on Tena Bar in 1980, about 3000 days after the hijacking. The find presents a plethora of problems to Cooper sleuths. The big problem is it is very far away from Cooper’s calculated landing zone near Ariel, Washington. There are no watersheds that could conceivably bring the bills to the Columbia River at Tena Bar, suggesting the landing zone was wrong. Unfortunately, no other evidence supports the landing zone being wrong.

The other problems deal with the bills themselves, their condition and location. Packets of American currency that are thrown into water sink. The bills themselves fan out. Tom Kaye, on his Citizen Sleuths website, and in interviews in other books I have read, has shown, rather conclusively, that there are no natural means by which the money could have gotten to the Tena Bar in the condition they were in, the location they were in.

If you are not aware, the bills were found stacked on top of each other, with the rubber bands still attached. The bills were so perfectly aligned, the ink from their serial numbers bled into each other without variation in location. To have three stacks of money land on top of each other, somehow bury themselves in the sand on a popular fishing location, in less than a square foot of space, by natural processes alone, beggars belief. They had to have been buried there by human hands (Kaye, again).

Then there’s another problem, where’s the rest of the money? Cooper stole $200,000 dollars. The money was in a big canvas sack. The bills were all twenties, so we’re talking 10,000 notes. Only the three Tena Bar packs of money were ever found, and people were looking. Did Cooper, or a third party, somehow leave the three packs there by accident, when they came to recover the money? Just, forgot? Cooper probably had to cache the money upon landing. But why would he cache it so far away? at a popular location? and then lose three packs that should have been in the bag?

Many Cooper Aficionados believe the Tena Bar money is a bigger mystery than anything else about the hijacking. It presents an apparent paradox (the context of which can be understood by watching a long playlist  regarding Dan Cooper on YouTube). To explain how and why the money got there is a central question in Cooper Lore.

So what is my answer?

If you read descriptions of the actual hijackings, it is universally accepted that Dan Cooper offered at least two, and possibly all three stewardesses, a stack of money as a tip. And all refused to take any money. Cooper spent five hours practically alone with one of the stewardesses, Tina Mucklow. He even waved goodbye to Tina before jumping, she was the last person to ever see him. His behavior was quite empathetic through much of the hijackings, he even ordered food for the flight crew, and supposedly brought OTC amphetamines for the crew in case they got too tired.

So what does a sophisticated hijacker do with three bundles of money he offered as tips to the young stewardesses whom he knows he scared and consequently feels guilty about? He leaves the money behind, almost as an offering to Karma. An expression of guilt. A nice gesture. And what better place than Tena’s bar (which, incidentally, has a sign at the entrance that spells it “Tina’s Bar”)?

This explains why the money was left by the hijacker, where it was left, and explains the amount of money left behind. Cooper felt guilty, probably because after talking with a stewardess for five hours, he made an emotional connection to her (Mucklow), and by association Flo and Alice (the other two stews). They wouldn’t take his money, so once he came back to the area to recover the loot, he left their tips behind, at the not-too-subtle location of “Tina’s” bar.

Like all Cooper theories, there are problems with my hypothesis. Cooper offered stacks of 100 bills, worth $2000 each, to the stewardesses. So Ingram should have found $6000. His find was $200 short. Turns out, that money might have been lost to the elements. PCGS found evidence of 35 additional serial numbers in the fragments. That’s an additional $700. Which is great, it closes the gap on my theory, and presents another problem: there’s no reason for that extra $500 to be there.

The Cooper mystery is something else…

 

Update: It looks like my theory could still hold true, from n467us.com: The money was provided by Seafirst bank which is now Bank of America. The money had been earmarked for situations such as these and was always on hand. It had been photographed and serial numbers recorded by their security so the FBI did none of this.

“The money was then transported by SeaFirst bank security to a Seattle police detective who then drove it to the airport and handed over to NWA. The money was bundled in various counts so that no bundle was the same. Each bundle was secured by rubber band and different counts so that it appeared the money was hastily gathered.”

Update II: It should be noted, after I poked around a bit, several others on the Drop Zone Cooper forum have also theorized the location of the money on Tena’s bar was symbolic.

Update III: After doing extensive research for an upcoming paper on Cooper, I did find FBI testimony stating money fragments were found three feet deep in the sand. This would mean it was not intentionally buried.

2012 pWP Recap

So… this only took two years to get around to…

My pWP stat is just an easy way to understand and aggregate multiple polls into a single, simple statement: Candidate X is (blank) percent likely to win his or her race. I’ve written a bunch of stuff on pWP, just in case you need to catch up.

A majority of the time, I was only paying attention to the presidential race in 2012. I did not keep up with the various other races. In the presidential race, with its many polls and good data, I went 50-51 in predicting where electoral votes would go (I did not pay attention to Maine or Nebraska’s split-vote system, as there was no need, there were no swing congressional districts in either state). The only state that pWP got wrong was Florida. Which makes sense, Florida was the closest election, with .88% (i.e. less than 1%) difference. However, looking back, had I eliminated an obvious outlier poll, or if I had looked at the median pWP instead of just the mean, I could have gotten closer to the right answer. Bad polls essentially remove the basis of pWP, so finding and eliminating them is a key challenge.

In addition to the presidential race, I made predictions on election night in seven other tight races (6 Senate, 1 Congressional) and I went six for seven. The race I got wrong was the North Dakota Senate race between Berg and Heitkamp. Once again, this was a close race, within 3000 votes. It was the closest Senate race, and relatively poorly polled. There were no polls done in November, and Heitkamp had closed a large gap in the last month of the race. About the only way I could have avoided being wrong in my prediction would have been to not make a prediction at all. Trendlines, using a rolling average, would have projected a 50-50 race. Basically, if there’s little to no current polling, and previous polling shows a tight race, skip the prediction.

The end result of using pWP over the last several election cycles has shown the stat has been a better predictor of the outcome of the race than it should, based on its probabilistic premise. Which means pollsters are doing, at least lately, a better job than even they suggest when giving out their margins of error. I don’t know if this is accidental or purposeful. It could be the way I’m aggregating the polls (when available). I don’t know. But good news is good news.

The bad news is those same polls that were really accurate over the last few election cycles show Dayton and Franken cruising to easy victory. The few partisan polls available in the 7th and 8th Minnesota congressional districts show easy DFL victories as well.

Update: Spoke too early, a non-partisan poll has Mills up on Nolan by almost four standard deviations. That’s over 90% pWP, but I would put it closer to 75% because the strong support for the Green candidate will fall, and the 11% undecided number is too high.

ROI of College Going Way Down

It’s fall, and that means college for millions of kids who have no idea why they’re going back to school even after The State has freed them from the educational industrial system (i.e. the little rooms ruled by the boring adults they were locked up in for twelve years). It also means the media will report out-of-context statistics about the value of college to fool people into wasting more time and money on a failing asset:

“Despite falling wages and rising tuition costs, the value of a college degree is still unquestionably high, a new report shows.

A college degree today is worth $272,692 in lifetime wages — more than three times its value in the 1980s ($80,000) and more than double its value in the 1970s ($120,000), researchers from the Federal Reserve Bank of New York found. At its highest point, in 2001, the net value of a college degree was $338,000, according to raw data from the report.

But the Great Recession, which brought widespread underemployment and record-breaking student loan debt for college graduates, has greatly slowed that growth spurt. The value of a college degree has fallen 11% since 2007.”

I grabbed the graph in the article:

NPV Bachelors Degree

Looks like a good deal, but… context. Net Present Value is great, if it is presented with other metrics like opportunity costs and return on investment (ROI). A quick Google search finds the following graph about the rising costs of college (and this graph is in agreement with hundreds of others based on universally accepted data):

total-cost-of-college-vs-other-goods1

As one can see, the costs of college are quickly approaching the NPV of a college education.

In 1980, you are getting a 6:1 return on investment with a college degree, but by 2006 you’re down to 2:1. And remember, NPV here is calculated for the lifetime of the graduate. Most investments that take fifty years to get the full return on investment are expected to do better than a simple doubling (this is a gross simplification of NPV and ROI, I know we’re not technically talking about a “doubling” of the investment, but there’s no reason to get too complicated here.)

Since all resources have alternative uses, what if you took that 120,000 dollars and invested it in the world economy through something like Vanguard’s Global Equity Fund? It turns out you can expect a 9% annual return (assuming a lack of alien invasions or deadly meteors or other calamity) on that investment. This investment has a NPV of $322,000 assuming a 2.2% annual inflation rate. If you add four years of full time work at minimum wage to that number you get $386,000 dollars. So not going to college, getting a job, and investing the resources it would take to go to college and putting them in the market gets you a larger return than a college diploma. This is just an example, I obviously don’t have the clairvoyance to predict if the global economy will grow at such a rate. I present it only to point out what is missing from the article.

The value of a college diploma is going down while the costs are going up in a flailing national economy that has a ridiculously high underemployment rate. Borrowing to pay for college is considered a wise move by most of the people talking to these kids. Someone needs to present an opposing view so they understand the risks. In my view, college students are heading towards a cliff. And the rest of us, especially our media, need to get serious about the problem.

Interesting Abstract

Taking notes on laptops rather than in longhand is increasingly common. Many researchers have suggested that laptop note taking is less effective than longhand note taking for learning. Prior studies have primarily focused on students’ capacity for multitasking and distraction when using laptops. The present research suggests that even when laptops are used solely to take notes, they may still be impairing learning because their use results in shallower processing. In three studies, we found that students who took notes on laptops performed worse on conceptual questions than students who took notes longhand. We show that whereas taking more notes can be beneficial, laptop note takers’ tendency to transcribe lectures verbatim rather than processing information and reframing it in their own words is detrimental to learning.

The Pen Is Mightier Than the Keyboard, Advantages of Longhand Over Laptop Note Taking. Authors: Pam A. Mueller, Daniel M. Oppenheimer

Source, Link to Paper.

The Corrigan Diet

Douglas Corrigan, beyond being a character in my latest novel, was also an immensely fascinating person in real life. A pilot/engineer/mechanic who once crossed the Atlantic Ocean in a heavily modified aircraft, much to the dismay of federal regulators, he starred as himself in an autobiographical movie (which is totally worth watching, if you ever see it scheduled on TCM) and continued to work in aviation until his retirement. He once wrote to a fan that he had “no hobbies except working on airplanes or machinery”.

Corrigan was famous for working on aircraft in marathon sessions. He often slept in aircraft hangers. Corrigan was known to miss meals and completely forget about eating. And one can tell, even from photos of him later in life, he kept an unbelievably trim figure throughout his life.

When I first read about Corrigan, and encountered these two facts about him (his devotion to work and forgetfulness about food), I realized this could really be a fantastic paradigm for dieting. If you fill your life with activity, be it mechanical work at an aircraft hanger or just cleaning your basement. The more you do, the less time you have for obsessing over food. As I’ve lived my life, I have focused on filling my life with activities that are outside the home, involve physically moving, and take mental energy. The result has been modest but satisfactory weight loss. If you spend any amount of time reading about bariatrics, you will see many stories of men and women who never left their home, ate while at home, and didn’t do anything with their lives, other than eat.

Don’t let that happen to you. Get out of the house. Douglas Corrigan would approve.

 

Chart of the Day:

minwage

Source

Tech is bad for Kids

Also, good parents are good for kids.

New York (Reuters) – Recollections of strict, unaffectionate parents were more common among young adults with an unhealthy attachment to Internet use, compared to their peers, in a new Greek study.

Young adults who recall their parents being tough or demanding without showing affection tend to be sad or to have trouble making friends, and those personality traits raise their risk of Internet addiction, the researchers say.

“In short, good parenting, including parental warmth and affection, that is caring and protective parents, has been associated with lower risk for Internet addiction,” said lead author Argyroula E. Kalaitzaki of the Technological Education Institute (TEI) of Crete in Heraklion, “whereas bad parenting, including parental control and intrusion, that is authoritarian and neglectful parents, has been associated with higher risk for addiction.”

Duh.

SOURCE: http://bit.ly/1m8inLg Addictive Behavior, online December 8, 2013.

Why Everyone Screws Up Their Retirement

Because it’s math.

It’s actually not really all that mathy. Whenever you get a paycheck, move the decimal one space over to the left, and throw that amount of money into a separate account that you don’t draw money from except for emergencies. If you want to really get complicated, put that money into an IRA and spend an afternoon looking up “index funds” on the internet. You’re done. As long as you work during your working years, it will be impossible not to have a retirement fund. Avoid debt like the plague, and you will live within your means and not be broke. For most people, this is enough, and yet most people can’t accomplish this simple setup (we’re going to exclude people suffering from some calamity, for simplicity).

I always wondered why, and I have talked to scores of people over the years about finance, and as far as I can tell there are two complaints. One, it’s boring. Two, it’s math. (In fact, #2 explains #1; people assume it’s boring because it’s math.) Students, if they learn nothing else from our public schools, learn math is boring. No amount of persuasion can change this attitude.

The consequences are awful.

Money is the foundation of modern life. We work. Why? Well, among other things, it gets us money. We want goods and services… what do we need? money. We have families, how shall we feed them? Whatever we do, we buy it with money. Everyone is obsessed with money. Our entire culture is centered around it. And yet, despite the fact we’re slaves to money, many of us don’t want to talk about it, read up on concepts relating to money, or find out ways to make ourselves less of a slave to money.

Money is literally numbers. Our currency is math. It’s not gold or silver or hours of labor. Our medium of exchange are numbers, just numbers, often printed on paper.

The only way to be successful with money, and therefore be successful in life, is to defeat the mathophobia. And that’s impossible.

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