Finale

Sequel sucks.

Not that I have fewer opinions on what's happening around, but the cost - both social and opportunistic ones - is too high to get my view expressed. For some quick and sensational comments (as well as good books that I read), I shall put them up on Facebook.

So, this is the end of my blog. As F.A. Hayek said in The Road to Serfdom:

If we are to build a better world we must have the courage to make a new start - even if that means some reculer pour mieux sauter.

Happy new year.

Player

Recently read: Ellery Queen 《The Player on the Other Side》（中譯本）

Name

Recently watched: 新海誠《你的名字》

Excellent plot and brilliantly excecuted - although if I were Makoto Shinkai, I would have make Miki Okudera turns out to be Mitsuha Miyamizu five years later.

Considerations

Although Abraham Wald did bring up an important and influential point, I must say I am not entirely satisfied the computation.

A few issues here. To begin with, the degree of protection is probably not directly proportional to the thickness of the armor - at some point there should be a plateau of the relation curve.

Second, it was assumed that the bullets were fired randomly and evenly, so that the density of bullet holes on each part of a surviving plain was inversely proportional to the vulnerability of that part. For obviously reasons we know that's not correct. To go one step further, with the data and knowledge of the survey, pilots of the adversary air force would try to focus more often on the vulnerable parts, resulting in a negative feedback.

Moreover, there are parts that are intrinsically protected and therefore have a lower chance of being hit by bullets. For example, the medial surface of the engine could not be easily hit. If you want an extreme example, the wheels and tire could hardly be hit because they are hidden inside the plane while flying. Alas, you won't put armor on the tire, will you?

Missing

My recent leisure reading is about the life and time of Abraham Wald, who was famous for, amongst his other contributions to mathematics and decision theory, the story of the missing bullet holes.

To put it simply, Wald was a mathematician born in the then Austria-Hungary Empire and moved to the States when Nazi took over his country (around the same time with Captain Georg von Trapp of The Sound of Music). He had most of his academic career at the Columbia University.

During World War II, Wald was involved in a project to minimize bomber losses to enemy fire. In short, the US Navy conducted a study of the damage done to aircraft that had returned from missions. The original idea was to add armor to the areas that showed the most damage. In contrast, Wald argued that reinforcement should be made in the areas where the returning aircraft had least bullet holes, since those were the areas that, if hit, would cause the plane to be lost.

Simple, eh? The actual calculation is a lot more complicated. For fans of pure mathematics, you may like to go through Wald's original report, which is a 90-page text available at http://www4.ncsu.edu/~swu6/documents/A_Reprint_Plane_Vulnerability.pdf

Link

I end up solving my problem accidentally.

And it is easy. I create a conventional short-cut for the file that I want easy access, and then copy that short-cut to the Evernote page - in which it appears as an ordinary file with "lnk" as the extension. When it is double-clicked, the original file in the hard disk is opened by the usual program. (I try it on all Microsoft Office applications as well as SPSS files.)

The point is, if the original file is in Google Drive, it would then be synchronized automatically after saving. You can access the same file from different Evernote pages because you just put hyperlinks rather than the original file in the page. Moreover, if you are the rare species who works on two computers with the same Google Drive, the link would still work in both computers - as long as the filing structure (i.e. the path name) of the target file remains the same.

And it works equally well if the link is made to a foler rather than a single file.

Problem

Although there are two official ways to put a file in the page of Evernote, each has its own problem.

First, putting a file directly into the note page means that it is detached from the original hard drive folder that keeps many of the related documents. Although it is theoretically possible to put several files into the same page of notes and make it function as a folder, there is a size limit of the file and you lose the hierarchy of a folder system. Moving attachment files across note pages is also cumbersome.

(By the way, there is an "Import Folder" function of Evernote, which seems to be an attempt to take over the conventional folder function. It is absolutely hopeless.)

How about linking up with the Google Drive?

Not much better an option really. It is ridiculously difficulty to find the file you want to link up because the dialogue box does not follow the tree-like filing system. You need to define the program for opening Microsoft Office files need to be opened. And, above all, it doesn't work when you are off-line.