Friday, March 28, 2008

This i want to read ...

http://www.gp-field-guide.org.uk/,
Genetic programming is cool!
And someday i hope to use it consciously to fix a problem.
This has just enormous potential to benefit mankind in general!
So it's on the "must read-list"
i'll try and post that list sometime soon because there are really interesting books on there through wich anyone could have a mindexpanding experience!

But now i'm off for a three day seminar to get some issues handled! (Excited!)
To quote David D. "The boy must die in order for the man to live."

May your day be wonderfull!

Thursday, March 20, 2008

Chaos, the way of the future.

Today I had a very interesting conversation with Robin Rowley,
I was introduced to him through Leen, a friend of mine, as her lecturer at the Plantijn Hogeschool. Some time ago, when i was talking with her and Tom about my plan for my future, she mentioned him as someone who I should talk to, and she was right.
He's an expert on Communications, Organisation Behaviour & HRM, Entrepeneurship, Strategy and Change Management. And this is exactly the field that's been calling to me for almost half a year now, drawing me away from my present career in biology.
He has also written a book, "Organize with chaos", available at Management Books 2000, of which he was so kind to give me a copy of the previous edition, the new one is just out.

A man's mind stretched to a new idea never goes back to its original dimensions. And this hour he gave me today was certainly a mindstretching experience!

I'm kinda very busy finishing this neverending masterthesis so i'm right now not able to do a lot with the new idea's and insights but this will come soon enough!

As a preparation for this conversation i read this introduction on Chaos and Complexity:
http://complexity.orcon.net.nz/index.html

It's by Victor MacGill, a very interesting person who's website i will discuss soon, but this link from his website was too nice to keep from you:

Wednesday, March 12, 2008

Stonehenge reloaded

There's this guy,
and his name is Wally Wallington
and he does some amazing things!!



Here's his website with explanation

If anyone ever tries to tell you aliens were needed for the construction of the pyramids ... show them Wally's website!

Thanks to Pieter

Monday, March 10, 2008

AdSense

Hmmm, blogger has been telling me i can make money with my blog if i put banners on it, being curious by nature (and facing a huge mortage) i clicked on it, and for now, as long as i don't really register, "non-commercial" ads are being shown..
I don't make any money of it, but a seemingly worthy cause is drawing attention to itself .. not a bad thing i think!
Let's try it for a while.

Tired

This morning something (probably myself) woke me at a quarter past 5 and apart from some lingering and turning around, i couldn't sleep anymore so I got up (and posted the previous post among other things)
in the afternoon i slept a few hours because i was just wasted, and now i'm still tired..
Anyway, maybe i should stop whining, bitching and complaining and make some stuff happen!
As Og Mandino says: Those who are weak, wait for opportunities. those who are strong, make them. Opportunities! Your life is full of them.
(i'll post some more thing about Og in the future)
I think i'm going to use this oppotunity of being tired to get some sleep :)

Have a nice day!

Early morning math! A game theoretic approach to the toilet seat problem.

If you ever find a woman who will agree with the following (really agrees and not just pretends and makes you pay for it in many other ways), let me know!

Necessary disclaimer: I said "agree" not "understand", I know many intelligent women and some of those are even way more intelligent than I am, understanding it is not the issue here. This is really not about intelligence nor is it about logic.

A GAME THEORETIC APPROACH TO THE TOILET SEAT PROBLEM
By Richard Harter

from The Science Creative Quarterly

The toilet seat problem has been the subject of much controversey. In this paper we consider a simplified model of the toilet seat problem. We shall show that for this model there is an inherent conflict of interest which can be resolved by a equity solution.

Consider a bathroom with one omnipurpose toilet (also known as a WC) which is used for two toilet operations which we shall designate as #1 and #2. The toilet has an attachment which we shall refer to as the seat (but see remark 1 below) which may be in either of two positions which we shall designate as up and down.

Toilet operations are performed by members of the human species (see remark 2 below) who fall into two categories, popularly designated as male and female. For convenience we shall use the name John to refer to the typical male and Marsha to refer to the typical female.

The performance of toilet operations by John and Marsha differ in a number of respects. The costs of these operations are peculiar to the respective sexes and are fixed except with respect to the position of the toilet seat. In particular:

Marsha performs toilet operations #1 and #2 with the seat in the down position. John performs toilet operation #1 with the seat in the up position and toilet operation #2 with the seat in the down position. If the seat is in the wrong position before performing the toilet operation the position must be changed at an average cost C. Optionally the position may be changed after performing the toilet operation, also at an average cost C. (Changing the position of the seat during the performance of a toilet operation is beyond the scope of this note and is definitely not recommended.)

Consider the scenario where John and Marsha each use a separate toilet. It should be obvious to the most casual observer that each minimizes the seat position transfer cost by not altering the seat position after performing a toilet operation.

For Marsha the seat position transfer cost is 0 since all operations are performed with the seat in the down position. For John the cost is greater than 0 since seat position transfers must be performed.

Let p be the probability that John will perform a #1 operation vs a #2 operation. Assume that John optimizes his seat position transfer cost (see remark 3 below.) Then it is easy to determine that John’s average cost of seat position transfer per toilet opeation is

B = 2p(1-p)C

where B is the bachelor cost of toilet seat position transfers per toilet operation.

Now let us consider the scenario where John and Marsha cohabit and both use the same toilet. In our analysis we shall assume that John and Marsha perform toilet operations with the same frequency (see remark 4 below) and that the order in which they perform them is random. They discover to their mutual displeasure that their cohabitation adversely alters the toilet seat position transfer cost function for each of them. What is more there is an inherent conflict of interest. Attempts to resolve the problem typically revolve around two strategies which we shall designate as J and M

Strategy J
Each person retains the default strategy that they used before cohabiting. This strategy is proposed by John with the argument “Why does it matter if the seat is up or down?”. As we see below this strategy benefits John.

Strategy M
Each person leaves the seat down. This strategy is proposed by Marsha with the argument “It ought to be down.” As we see below this strategy benefits Marsha.

Consequences of strategy J:
Under strategy J the toilet seat is is in the up position with probability p/2. The respective average cost of toilet seat transfer operations for John and Marsha are:

John: p(3/2-p)C
Marsha: pC/2

The incremental costs (difference between pre and post habitation costs) are:

John: ( p - 1/2)pC
Marsha: pC/2
Total: (p^2)C

John’s incremental cost would actually be negative if p were less than 1/2. This is not the case; p>1/2. Note that Marsha’s incremental cost is greater than John’s for p<1. Marsha objects.

Consequences of strategy M:
In strategy M the seat is always left down. When John performs operation #1 he lifts the seat before the operation and lowers it after the operation. The respective average cost of toilet seat transfer operations is:

John: 2pC
Marsha: 0

The incremental costs are:

John: 2(p^2)C
Marsha: 0
Total: 2(p^2)C

In these strategy Marsha bears no cost; all of the incremental costs are borne by John. John objects. Note also that the combined incremental cost of strategy M is greater than that of strategy J.

It is notable that John and Marsha each advocates a strategy that benefits them. This is predictable under game theory. However the conflict over strategies has a cost M in marital discord that is greater than the cumulative cost of toilet seat transfers. It behooves John and Marsha, therefore, to adopt a strategy that minimizes M.

This is not simple. A common reaction is to advance sundry arguments to justify adopting strategy M or J. All such arguments are suspect because they are self serving (and often accompanied with the “If you loved me” ploy.) A sound strategy is one that is equitable and is seen to be equitable. In this regard there are three candidate criteria:

(1) Minimize the joint total cost
(2) Equalize the respective total costs
(3) Equalize the respective incremental costs

The argument for (1) is that John and Marsha are now as one and it is the joint costs and benefits of the union that should be considered. This principle is not universally accepted. It is readily seen that (see remark 5) that the joint total cost is optimized by strategy J which has already been seen to be suspect.

Criterion (2) seems plausible. It requires, however, that Marsha put the seat in the up position after performing a toilet operation some percentage of the time. No instance of this behaviour has ever been observed in recorded history; ergo this criterion can be ruled out. (But see remark 6.)

Criterion (3) argues that the mututal increased cost of toilet seat operations should be shared equitably, i.e., neither party should bear a disproportionate share of the costs of cohabitation. A short calculation reveals that criterion (3) can be achieved if John leaves the seat up after performing toilet operation #1 with a frequency

f = (2p-1)/p

Since the value of p is seldom precisely measured and is variable in any event it suffices to use an approximate value of f. If we assume that p=2/3 then f=1/2. This suggests the following convenient rule of thumb:

In the morning John leaves the seat up after performing #1.
In the evening he puts it down.

This rule may not be precise but it is simple and approximately equitable; moreover the use of a definite rule sets expectations. The seat is put down in the evening to avoid the notorious “middle of the night surprise”.

I expect that this analysis should settle the toilet seat controversey for once and for all - if John and Marsha are mathematicians.

* * *

Remark 1: The toilet has an additional attachment called the toilet seat lid which can only be down if the toilet seat is down. When the lid is down the toilet is (or should be) non-functional for toilet operations. Some persons maintain the toilet seat lid in the down position when the toilet is not use. For these persons the analysis in this note is moot. Such persons pay a fixed cost in seat movement for all toilet operations.

Remark 2: Toilets are also used by domestic animals as a convenient source of drinking water unless the lid is down. (See remark 1)

Remark 3: Experimental evidence suggests that almost all bachelors optimize the seat transfer cost, the exception being those who put the seat up after performing a #2 operation.

Remark 4: Folklore has it that Marsha performs more toilet operations than John, hypothetically because of a smaller bladder. John, however, drinks more beer. We shall not discuss his prostate problem.

Remark 5: “Readily seen” in this context means “It looks obvious but I don’t know how to prove it; you figure it out.”

Remark 6: The toilet lid solution is to put the toilet lid down after all toilet operations. This solution imposes a cost of 2C on each party and is accordingly more expensive. It is, however, more esthetic. It also eliminates the “doggy drinking” problem.

* * *

(REPRINTED FROM ISSUE ONE, MAY 23rd, 2005)

Richard Harter is an eclectic auto-didact, a man of letters and software. By turns a mathematician, a software maven, and an entrepeneur, he has retired to the wilds where he tends his garden and his web site. He has a keen interest in science, the philosophy of science, and science fiction, and professes to have the wit not to confuse the three

Friday, March 7, 2008

Let's walk

Because of the course in mindfulness i'm following, i'm experimenting with mindful walking.
Focussing on the legs, the shift of balance that accompanies every step, focussing on the hips, sometimes using a mantra to accompany the different steps, etc

But sometimes i just walk like these guys ;)

Wednesday, March 5, 2008

So that's how it works ..

Just recently a few friends (Chris, Zeno, Lotte and Karo) explained to me the game that when you see a yellow car, and if you see it first, you can punch the person next you you ...
I thought it was a silly game ... but that's just because they didn't explain it fully !!

Luckily xkcd comes through once more

Saturday, March 1, 2008

hahahahahahahahahahahahahahahaha, so true


(http://assets.gva.be/Albums/GvA/Cartoons/slides/070509K.asp)

For those whose dutch urgently needs improving, a translation:

Title: The Netherlands are considering a ban on alcohol for people below 18

Male Officer: He was trying to make beer by boiling the water from the central heating system together with the dirty underwear of his grandparents.
Female officer: But that's actually not illegal ...
Male Officer: Heineken accused him of industrial espionage.

(Heineken is a really terrible beer when you compare it to just about every Belgian beer, but somehow they managed to merchandise it all around the world, despite the fact that it's just a disgusting excuse for beer.)