Fraud detection techniques for e-commerce. Part 1.

In this series of posts, I will develop different ideas about how fraud in e-commerce, and different techniques which can be used to counteract this type of behavior. Some of them are standard knowledge acquired at my time working in fraud detection, other are from the corpus of information that has been developed in the industry, also a couple of my own ideas which I would like to have implemented in the future.

Sources of fraud

Fraud in e-commerce has mainly a two sided profile : Payment fraud or product fraud. Either the money one applies to an operation is lost, or the received product represents a lesser valued than payed (Which is another way of lost money)

Credit card / payments processor fraud

Credit cards are nowadays the normal payment type of a online transaction, be it directly or indirectly through a payment processor.

Fraud types in payments have many ways of being perpetrated, but in this simple article, we will generalize and leave apart some of the more sophisticated, to bring a very general idea of the modus operandi on each regard.

Rush orders

This phenomenon occurs when a fraudster has access to credit cards credentials, and so he/she makes rush and overnight orders, to try to snap all possible credit he can before the card is reported.

The quickest shipping methods are also employed for this type of fraud, because once the product is on the hand of the buyer, the order cancellation won't prevent the goal of the operation, at least the primary one.

Product fraud

This source of fraud is related to the product owner "making believe" the buyer of the product quality, but in reality the intention is never to release the product. For this type of fraud, very attractive prices are set, and they are sold at a very high speed, so the user has a very short span of time between seeing, thinking, and buying the good. It also can be combined with the following technique, requiring the buyer to pay by means outside the control of the site.

Site mechanisms fraud

This type is the most frequent fraud type in online auction sites. The objective of this type of operation is sending the buyer information embedded in the product's media: Descriptions, photos, comments.

There are really interesting techniques in this regards, including optical character recognition of text patterns in the images, simple text pattern recognition, and even neural networks applying Natural Language Processing, and automatically getting text patterns associated with embedded information sharing, never before though from the analyst, learning from a list of positive previous cases.

Summary

In this first post, I've set a very minimum structure to develop different fraud detection techniques divided in a couple of main fields. Many other classification types can be employed, please let me know in the comments how this classification can be enriched and completed.

Next post series: Analyzing Aeolus Pipe organ synthesizer

In the next blog post i'll be posting my findings about Fons Adriaensen's Aeolus Pipe Organ synthesizer. I'll will try to explain to myself and the internet, the entire process of generating convincing pipe organ sounds.

The first batch of information is something that seems easy but it's not that way: Where is the last release of Aeolus located? Here (It requires some other libraries, like The stops, zita-alsa-pcmi-0.2.0.tar.bz2, clthreads-2.4.0.tar.bz2 and clxclient-3.9.0.tar.bz2)

The last release, 0.9.0, is pretty recent, and from the README, the changelog is:

AEOLUS 0.9.0   RELEASE NOTES   30/06/2013
============================

Maintenance release.

* Replaced libalsadrv by libzita-alsa-pcmi
* Changed license to GPL3

Next I'll be taking notes about Aeolus general architecture.

Unofficial Vatican TV Player for Linux: How to see the last days of BXVI as Pontiff in Linux

Given the important events happening today on the Vatican State, and the difficulty of watching the Vatican player on Linux (Silverlight version not compatible with moonlight), I'm building a simpler version that runs on a somewhat standard Linux distribution (Requires Moonlight and possibly the media codecs).

See how to install Moonlight

Right now it only plays the live signal of the CTV(You have to press play twice, seeing the pause symbol on the play button), but I plan to add the archives as well. Please let me know of any inconveniences, or if a better solution exists.

The URL: http://bit.ly/YJGbcm

Optimizing the performance of Gcc compiled programs for BeagleBoard

Researching the various ways to optimize the compilation programs for BeagleBoard, I've come with the following parameters for GCC:

-O3 -fomit-frame-pointer -mfloat-abi=softfp -mfpu=neon -mcpu=cortex-a8 -ftree-vectorize -ffast-math

At the moment they are the best parameters we could get. Maybe you have aditional parameters you use to speed the resulting program's performance?

Improving Beagleboard capture speed on OpenCV

It seems that the capture routines of OpenCV don't perform so well on the Beagleboard. Our  tests were really disappointing, with 2-3 fps on our low vision project.

We had to develop a custom optimized capture mechanism, which retrieves the raw YUYV frames, extracts the Y components, and works from there.

This allow us to grab at full camera speed at 640x480 for a Logitech Pro9000 camera, and we are optimizing to get the full resolution, 1600x1200.  Apparently SDL can be used to grab frames with improved speed, this is something we didn't consider.

PS: To have better information, see my next post

The Leibniz-Newton controversy

Studying the aspects that gave origin to the well known Differential and Integral Calculus right now.

The Royal Society Committee , which analyzed Leibniz plagiarism charges, and the two bands that emerged from it, are really a sign that the human race doesn't change too much through the centuries, and it takes a bit the mystic halo science has, showing that science is also a man business, specially observing Newton's actions, of almost supra human image in the eyes of some, and not really brilliant in the mentioned case.

It also comes as a conclusion that giving the unique authorship of Calculus to one unique person is at least very unfair, seeing the clear traces of preliminary works coming from the Greeks, and there is a list of really big names with fundamental works as Fermat, Descartes, Hooke, etc.

Ruby midi-speech synthesis crossover

Some days ago I had to somehow show all the sound of a .sf2 soundbank file. This can be a really boring and time consuming task.

So I hacked together a ruby script that says the sound number through MS Sapi, and quickly generated a scale midi file with changed instrument, and play it through Windows services, everything from register 1 to 99. It saved me a couple of hours maybe, and was indeed fun.

A little excerpt (recorded from a cheap microphone due to an integrated soundcard's inhability) can be found here

The employed libraries were midilib and win32-sapi .