O(f(n)) notation EXPLAINED... doh

UC Berkley Lecture by Computer Scientist and Physicist Dr. Jonathan Shewchuk, where he really explains a number of misunderstandings with this commonly used notation! It is also a good introduction for the inexperienced ones!

Here it is, enjoy:

Banking Bonuses

It is a sure way to climb the millionaires ladder :-) A path to riches is through the financial sector, and this has been so for many years. Recent criticism of Bonuses paid out to employees of Investment Banks / Funds have just achieved more advertising for these institutions for talented people.

At JPMorgan 1'626 staff received $1 million or more and 27 individuals walked away with a hefty 8 million bonus, at Goldman Sachs this was 21 employees. [source: Andrew Cuomo's recent report on Bank Bonus Culture]

Working at one of these organisations shifts the odds of becoming a millionaire in a lifetime considerably in your favour.

C# vs. C

So how efficient is C# really?? In relation to a language like C. Well the answer is, that there is no conclusive answer, yet a set of features of C# where performance matters is investigated in this nice MSDN article.

The article was written back in 2004, and much has improved in the C# world, and not just in terms of VM performance but the language capabilities aswell.

Large Search-Querry datasets

On a blog I recently visited, it was pointed out in context of a web search analysis study that: "This study also highlights the current situation in web-scale research: that only companies like Microsoft, Google or Yahoo! have access to the sheer volume of data needed to do such an analaysis." (sorry I do not remember the source of this, if it is ur blog please let me know, so I can reference you) This has been brought up numerous times in the past and I couldnt agree more. What is really very important is for society (/ internet users) to realise that they are the creators of the content and they should demand access to the agregatted datasets [Tapscott&Williams in Wikinomics - How Mass Collaboration Changes Everything]. Or in other words (since most people wouldnt know what to do with the datasets) some kind of compensation. This applies less to search engines, since they provide a free service, and applies more to other collaborative web 2.0 apps. However, search engines make money on advertising, so thats the reason why they are free to use, not because users are being compensated for the datasets that these search companies decide to store and aggregate.

My criticism is that search engines shouldn't keep the raw data hidden behind proprietary domains but open up to the world research community.

Submit your video into space

A pretty cool and interesting PR project launched by NASA, where you can submit a video clip on the topic of why you think space research is important!

check it out under:
http://www.nasa.gov/externalflash/myexploration/index2.html

Defending your digital freedom

We are overwhelmed by technology these days. Our lives evolve around going through our days being exposed to one or the other technical gadget or application. Without even realising it these collect all kinds of sensitive usage patterns about us.

There is an advancement in technology that has not yet been mirrored by appropriate and highly necessary legislation. Groups such as the ElectronicFrontierFoundation (see http://www.eff.org/about), which is an organisation dedicated to protect freedom of speech. Also backed by the World Intellectual Property Organisation.

Savers Prefer to Invest themselves!

An article that appeared today in the FT, according to an FT poll, savers feel safer and prefer to invest themselves rather than putting their money into investment banks.

http://www.ft.com/cms/s/0/0e13ea70-aba7-11de-9be4-00144feabdc0.html
(you might need to register in order to see the article)

Crisis Sentiments - pretty cool!!

BBC has made a google map that maps to opinions and comments relating to the crisis kicked off by the Lehman Brother collapse (various dates are associated with the crisis start thought). It is an interesting interactive World Wide Map, location point & click & read interface, pretty neat web 2.0 idea, so make sure to check it out!!!

check out my customised adds and comments

Intuition and Trading

There are numerous problems system designers face when tasked with developing IT Expert Based Systems. Such systems have to rely on a rule base from which inferences are made about a problem area(s), this is in a way the core idea behing an Expert System (ES). However the main problem is the acquirement of expertise or knowledge, if you like, into the rule base.

Numerous academic projects point out the fact that when traders were tasked with explaining some of their trading decision making processes, they were useless. The traders often explain that much of their decision making is based on intuition and that pin pointing explicitly, lhow they arrive to trading decisions is very difficult.

In a recent scientific experiment, two men with amnesia were asked to remember pairs of 8 objects (Nature July 28iss). Each man was shown the 8 pairs 5 times a day for numerous days. The man eventhought they could not remember why, learned to distibguish the pairs.

An excerpt follows:

When one of the men was asked if he picked an object because he remembered seeing it before, he said, "No. It just seems that's the one. It's here [pointing to his head] somehow or another and the hand goes for it."

Without being aware of it, the men learned the task after approximately 1,000 trials. This is about the same number of trials needed by monkeys with similar lesions in the medial temporal lobe. Normal monkeys take about 500 trials to learn the task.

The implication is that humans have an unconscious ability -- comparable to that in animals -- to mold our behavior in response to a consistent stimulus. "Habit learning is going on all the time. All of us are acquiring habits, " Squire said. "What this is showing is that habit learning is well-developed in humans, and that it works independent of consciousness."

This seems to indicate a strong relationship to intuitive learning, such knowledge that is acquired by traders via repetitive trading behaviour and performance feedback. In fact this is feedback learning and in IT terms it is synonymous with Unsupervised Learning, for cluster detection of patterns and inference. At least this is my interpretation, I am quite interested into past research of this kind... anybody who has a valuable opinion please bring your comments to the table :-)

Correlation

I just noticed today how good the wikipedia article on correlation is. This is worth a read, if not only for nice concise expressions, of the form such as "correlation or co-relation refers to the departure of two random variables from independence" and many others. Anyway, as we are talking statistics, do check out the highly related articles on Pearson's Correlation, and Standard Score.