Ones and Zeros

Today’s lesson is a review of everything I’ve done so far. Instructor M and I make a 1.3 hour flight where we sample all the BAI: steep turns, unusual attitudes, climbs, descents and everything else I’ve learned so far. It’s a busy session, but everything works out well enough.

My turns on the compass are better, but I mix up some headings: 130 and 100. M says that’s not uncommon from the way they’re marked on the compass. My compass turns aren’t dead right either, I have to correct some when I roll out what what I think is my heading. I’m having to think harder than I should about which way to turn on the compass. So more work on that as part of future lessons.

The tolerance in the FAA’s test standards is 100 feet in altitude and 10 degrees in heading. I seem to have taken that as permission to be 100 feet off altitude. M is expecting better of me, “Own that altitude, don’t let it change from 3000 ft!” This gets more interesting crossing the ridge with some temporary light turbulence. I do a little better and I’ll get a lot more practice in future lessons.

In short the BAI stage check went well. I need to be more precise in general but am pretty much where I should be at this point. The syllabus lists 18 more lessons (if everything goes smoothly). Next up is the navigation stage. Then comes flying approaches and finally the cross-country flight and polishing lessons.

I’m flying with instructor R today as instructor M is occupied. Both are very experienced and good teachers and I like them. We’re using the Cessna Pilot School program to I can move between instructors easily, their professionalism helps smooth this process too.

Instructor R and I have a constraint tonight. The airspace in this area closes at 8 pm for President Obama’s State of The Union speech. So it’s a shorter lesson and we just won’t go as far. Our agenda is to do partial panel, but also to review steep turns and do stalls.

After a brief of our plan, we loaded and started up (I’d already preflighted) then taxied out to the runup area. After the runup R gave me a clearance which I copied and read back. I know the CRAFT acronym for copying clearances (Clearance limit, Route, Altitude, Frequency, and Transponder code), but will have to practice copying them with some recordings from LiveATC on my iPod.
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Wired has a good article about the “quants” on Wall Street that precipitated the financial crisis.  David X. Li was the author of the formula that was used to manage the risk for bonds, mortgages, and other debt obligations.  However, the problem and crisis are not Li’s fault.  He routinely cautioned people, as did other math experts, that they were using the formula incorrectly.

The key points were that this formula tried to correlate the risk between different mortgages.  There were two sets of problems.  First, risk is not “normally” distributed.  The usual bell curve - a gaussian distribution - is called a “normal distribution”.  However not everything falls into this distribution.

Financial price series have been show to be fractally distributed, this is much wider so has more highs and lows than a normal gaussian distribution..  It’s not unreasonable to consider that risk also has a wider distribution too.

Secondly, correlation varies over time.  The Wired article goes into this in much more detail that I will repeat here.  But two separate loans that have a given correlation of risk over one time period may not always have that same correlation in a different period with different economic conditions.

In the end, the world is more complex that the Li formula allowed for.  This isn’t unusual.  Mathematical models don’t always model all aspects of a situation and they’re not necessarily intended to do so.  But if you ignore the discrepancies between the model and the real world you’re asking for trouble.  And trouble is where we ended up.

Barring a stock market crash, winning lottery ticket, or car accident, each new day is basically pretty similar to the day before. We wake up each morning look and feel pretty much like we did the morning before. Any changes tend to happen gradually over time as small differences accumulate in our lives. Enough drops of water, after all, will eventually make the amazon river.

Sometimes we see those changes as sudden but it is actually our realization of the accumulation of those drops of unnoticed moments. A memory, a particular date, or some event can trigger that realization.

Birthdays will do that to you though. I had a milestone one a while back. But I’m still thinking on it.

We all might at some time wish we were young again and had to years stretching before us with all their open-ended wealth of possibilities. But at some point, we realize that time is finite. We’re writing sonets and haikus with our lives now instead of the epic free verse we envisioned when younger. There are now more things I can never be, not because I might lack the ability, but more because I lack the time to gain the necessary experience.

We have strictures on us imposed by time and circumstance, and by our own choices and wishes. Many of those choices I celebrate and would do again the same way in my life. I’m fortunate since my big choices tended to work out well. But I see the range of possibilities for my wife and I starting to narrow.

I can’t do anything time moving forward. I can, however, make my choices more effectively. And with time comes (I hope) maturity to make those choices better. Perhaps that open-ended wealth of possibilities I saw when younger was partly an illusion anyhow.