I used Ghost for a while. It’s a simple and straightforward platform that simply gets out of the way and lets you write and publish a blog. And I’ve been a happy customer of the hosted version, paying a bit less than $100 a year for it. However, recently Ghost decided to raise prices by more than 100% and target a higher end market. At which point it’s hard for me to justify the expense. So I began looking for alternatives.
This is right in the intersection of Supply Chain and Artificial Intelligence.
This is one of the most interesting visualizations I have seen in a while. The folks at Kiln created a map of merchant ships around the world, including a breakdown of the contents of the ships, as well as CO2 emissions as a proxy for environmental impact. You can see a fully functioning version of the map below:
I found out that Google is open sourcing (more or less) the build system used internally, Blaze. The open source version is called Bazel.
The Astronauts, the team behind The Vanishing of Ethan Carter, just published a great summary of how they are using photogrammetry in order to create some of the most realistic 3D scenes ever seen in a game.
Dave Cutler is one of the best software engineers in Microsoft, and arguably in the entire world. The Microsoft News Center recently published a long feature on Cutler’s contributions to the company, which covers his many decades of revolutionary work in the industry.
Right before the end of last year I finished the second Supply Chain Course on edX. This was a fantastic course, easily the best one I’ve taken online, and probably the most useful for my day to day job (in Supply Chain of course).
Springer, the academic publisher, has been maintaining an open access program for a while. They have released thousands of books in their website, free to download. Apparently it’s been going on for a while but I only found out recently.
Andrew Ng is one of the world’s top experts in Machine Learning, and had a tremendous influence making Deep Learning a popular technique for problems in speech recognition, image captioning and many others. In particular, he was one of the founders of the Google Brain group a few years ago.
A few days ago I read an article on Nature Scientific Reports about Fungi in the brain of Alzheimer’s Disease patients.
Lately it’s been “supply chain this” and “supply chain that” for me. So here is another blog post about Supply Chain! I’ve been studying for two online courses in EdX: I talked a bit about the first course in a previous blog post, and I just started the second part.
Please check also the first blog post in this series about Supply Chain.
I can’t believe I didn’t read Snow Crash until now. Snow Crash is a novel by Neal Stephenson in which he introduced the Metaverse. What we would call today a virtual reality world. While I was reading it, I had to remind myself that the book was published in 1992. More than 10 years ahead of Second Life and WOW.
I recently switched jobs at Google. After two years working in Ads I decided that I needed a change, and I joined the Supply Chain team. Five months later I can start to recap my experience.
The last few months I’ve been using a Jawbone tracker. It’s a small bracelet which keeps track of steps and sleep patterns. And it’s been very useful to help me sleep a bit longer. From what I understand most people don’t get enough sleep, so I recommend checking it out. A while back I achieved a nice milestone. A thousand hours of sleep and one million steps.
I recently ported the blog to Ghost. Now it’s time to say goodbye to AppEngine. I had to make several updates in order to keep the application running, and the amount of work was just too big to justify. Now I happily let Ghost run the blog and I just write.
Yesterday I finally finished porting over the blog content from the old platform into Ghost. And today I set up a new mailing list using MailChimp. The updates to the blog are almost complete…
Let’s see how this works out. New blogging platform. Hello Ghost!
Everybody who has spent some time working in a business of any size knows that Excel is ubiquitous. It’s surprising that there are so few companies out there working in the spreadsheet world.
A new detailed simulation of the universe:
A raytracer in the back of a business card! Here is the code:
One of my favorite features from github is the activity chart that appears in the user profile. For example, this one from user jmcnamara:
Hello, internets! I just redesigned the look & feel of the blog. The new design has bigger font sizes and less distractions. It's optimized for mobile so it should look much better than before on Android and iOS phones, and especially on iPad.
A few weeks ago I had the chance to read Masters of Doom by David Kushner and found it very interesting. It tells the story of John Carmack and John Romero, the founders of id Software and authors of some the most revolutionary videogames ever.
A while back I found a beautiful website on Mathematics and I wanted to share the link: Mathigon has a series of introductory articles and many images, figures and interactive visualizations on a variety of mathematical topics.
I guess this is the advanced version of the companion cube:
I haven't done any kind of 3D design in many years, but I was thinking last week that it would be fun to get back to it. And while I was looking at software available for Linux, I found Blender.
A primality test in one line of Perl:
I haven't had much time to write lately, work is keeping me busy. But today I wanted to share a site I found recently and I think is really interesting. It's essentially a git tutorial, but with a twist.
A team from USC engineered microscopic markers that light up synapses in a living neuron in real time.
Project Loon is a network of balloons traveling on the edge of space, designed to connect people in rural and remote areas, help fill coverage gaps, and bring people back online after disasters.
A few days ago I found out about codesearch. It's a group of command-line tools to index and search code using regular expressions. It was originally developed by fellow googler Russ Cox. It uses the same algorithms that were behind Google Code Search.
A stop-motion movie made with two-atom molecules.
A few weeks ago I gave a small webinar for a group of students from MIT.
Over the last few months I have been going to a few technology meetups here in Seattle, and I enjoyed it very much. It's great to see all the cool technology that local companies are creating. Here are three of the most popular tech meetups in Seattle:
Card Games, Complete Subgraphs, Constant Weight Error Correcting Codes and Finite Projective Geometries
I was recently in a store buying a gift for a friend and found a card game that seemed interesting. The cards have small symbols which are arranged in a way such that between two cards there is always one symbol in common.
Probably everyone that is reading this post knows that Google has decided to discontinue Google Reader. This comes as a surprise to many because of the large and very passionate user base, including myself.
An electron microscope has imaged threads of DNA directly for the first time:
On December 3rd, the world’s governments will meet to update a key treaty of a UN agency called the International Telecommunication Union (ITU). Some governments are proposing to extend ITU authority to Internet governance in ways that could threaten Internet openness and innovation, increase access costs, and erode human rights online.
A few days ago I had the chance to watch a talk by Steve Souders, who is one of the world's top experts on website performance. I started thinking about how to apply some of the techniques that he mentions to my site, and I decided to replace the icons that appear at the top. These are links to subscribe to blog updates, the RSS feed, the feedburner email subscription, and links to twitter and Google+, which I update when there are new blog posts. I decided to replace these image icons with icons made using only CSS.
I've been using emacs for a few years now. And even though I am not an expert I appreciate how powerful it is. It never ceases to amaze me how many configuration options are available.
Today, I'm just going to do a little bit of self-promotion. A few days ago Google announced the launch of the new Chromebook.
Today I would like to share a Youtube video course on the History of Mathematics. I haven't watched all of it, but I liked the part that I saw. Here is one of the videos, on projective geometry:
Like many Software Engineers and Computer Scientists, I've always been interested in Artificial Intelligence (AI). When people outside of the field think about AI, they normally think about computers that can behave like humans in the real world. This branch of AI is called Artificial General Intelligence. And despite how popular it is in science fiction, in the real world there has been little progress towards the goal of creating an intelligent machine.
Today I'm just going to share a little bit of code to download content from the DataStore in Google AppEngine. A few days ago I was worried about not having a recent backup of my blog. So I decided to write some code to download all the blog content in a convenient ZIP file. Here it is:
I was recently in the Denver area, and while driving around I saw directions to a place called Mesa. This reminded me of Black Mesa, which is the location of the original Half Life game. The game actually starts after some kind of nuclear accident, which opens an inter-dimensional portal.
There is a wide variety of Mathematics used at Google. For example Linear Algebra in the PageRank algorithm, used to rank web pages in search results. Or Game Theory, used in ad auctions, or Graph Theory in Google Maps. At Google there are literally dozens of products which use interesting Mathematics. These are not just research prototypes, but real Google products; in which Mathematics play a crucial role.
Recently I've been learning a little bit about Google Guice (pronounced like juice) and dependency injection. In case you are not familiar with dependency injection, a good introduction is this article by Martin Fowler.
I would like to share a quick note about some writing tools that I've been using lately.
In an international scientific breakthrough, a Griffith University research team has been able to photograph the shadow of a single atom for the first time.
At some point or another, pretty much everybody has had to bulk process all the images in a directory. Either to resize them to a smaller size to share them, or do some other simple transformation.
Normally I write all the posts in this blog manually, including all the HTML, paragraphs, links, images, etc. But a few days ago I found a great in-browser HTML5 editor, http://xing.github.com/wysihtml5/.
If you are not familiar with Synthetic Biology, you should watch the following video. It's a very well made introduction to one of the most promising fields in technology.
Welcome to the new sleek and minimalistic design of the blog!
Two very cool pieces of technology that I saw in the news recently:
During the twentieth century the life expectancy grew from an average of 47 years to about 70-80 years, in part because of improved healthcare and hygiene as well as the development of antibiotics and vaccines. In some places even greater incidence of extraordinary life spans has even been observed, like the Okinawan Japanese, who have the highest number of centenaries in the world.
This cannot be explained by the same improvements that led to the extension of life expectancy elsewhere in the world. The quest to unveil the reasons behind their increased longevity has captured the mind of biogerontologists, who have spent decades investigating the causes, mechanisms and consequences of aging. Dr. Aubrey de Grey, the leader of the strategies for engineered negligible senescence (SENS) foundation, suggests that
Aging exists in nature for just the same reason that aging exists in man-made structures and machines: it is the default, and genes are required to combat it, just as mechanics and their ilk are required to combat the aging of man-made objects.
Today, with the help of modern medicine and science, researchers have been making great progress in understanding how the aging process works and how we can control or even reverse it to some extent. The SENS foundation (and its affiliated researchers) has been pivotal to this effort, being involved in bringing innovation such as rejuvenating the immune system to better fight disease in later years or using stem cells to treat Parkinson's disease. Other unaffiliated biogerontologists have also made remarkable advancements like the development of a drug that might reverse aging-related decline of the brain.
While these new techniques and breakthroughs are very exciting, we are still at least a few decades away from seeing practical applications. However, there are two lifestyle factors which can have a remarkable effect on how we age, and are well within our control: exercise and diet. Exercise is a good strategy to stave off secondary aging (aging that comes as a consequence of disease), as it can be seen by its effect on the health of people suffering from kidney disease or in the prevention of damage linked to Alzheimer's disease. A good diet can not only have benefits when it comes to secondary aging, but it can even extend the maximum life span slowing down primary (disease independent) aging.
Diet and life extension
When it comes to diet, attention tends to be immediately drawn to healthy eating (something that nutritionists have been advocating for decades) as the ultimate goal, but even more can be potentially accomplished with dietary change. A very successful strategy for increasing life span is, in fact, calorie restriction. Something as simple as reducing the amount of energy we obtain from food beyond the recommended daily intake levels, while ensuring that the diet still includes enough nutrients.
Although this idea might seem counter-intuitive, eating less may make it possible to live longer. Several studies conducted on animals prove that. In particular, studies on mice reveal a very interesting trend. Individuals which had a diet with the full recommended daily dosage of nutrients but with calorie restriction lived longer if they started on a calorie restricted diet early, just after their growing period. In fact, such a strategy extended life up to an incredible 80% in young animals and still provided a 20-30% increase in lifespan of animals which were already middle-aged by the time their diet was changed. Still, the benefits did not stop there, not only did the animals live longer, but they were healthy throughout the course of their lives. In Rhesus monkeys (who share more in common with humans than rats), long-term studies are now being carried out and preliminary reports (at a stage where monkeys have reached their average life expectancy) point to a three-fold difference in deaths due to age-related illness between a calorie restricted group and monkeys fed a regular diet.
How calorie restriction works
Our bodies accumulate energy in the form of a reusable molecule, ATP. Every time we breathe, move or even think we use ATP, which then needs to be recharged. That happens in specific sites in our cells, the mitochondria, which are structures akin to power stations, where a number of complex reactions (which depend on the presence of oxygen) spring life back into the ATP molecule in a never ending cycle. However, sometimes that operation malfunctions and the oxygen we breathe (which is essential for the whole process) is affected in an undesirable fashion, creating damaging molecules which would cause havoc if left to roam free. To stop these molecules our cells have mechanisms designed to neutralize them, a task at which they are fairly effective during youth (although damage often starts decades before any symptoms are evident). But they become less and less so as the years go by, when damage progressively becomes rampant.
This accumulated damage is likely to be behind the cellular "garbage" which causes Parkinson's or Alzheimer's disease; chronic inflammation responsible for rheumatoid arthritis or atherosclerosis; changes in lipid metabolism, which lead to type 2 diabetes and muscle loss; and many other diseases which tend to lead to premature death. Calorie restriction has been shown to reduce the rate at which all these different types of damage occur and, while the exact molecular mechanisms are not yet clear, is likely to do so on two fronts. First, by increasing the efficiency of the mechanisms that prevent damaging oxygen molecules from having detrimental effects. Second, by reducing the amount of damaging oxygen molecules from the start. In addition, it is hypothesized calorie restriction might reduce the metabolic rate itself. This would be in line with the observation that calorie restricted animals tend to have lower body temperature, but further research on the subject is still needed.
You can live longer too
Human trials conducted so far support the hypothesis that calorie restriction is a valid and useful method in extending life span. Despite the relatively short duration of the experiments, several studies show calorie restriction has the ability to reduce the effects of secondary aging (for example by starving cancer or reducing the severity of diabetes and cardiovascular disease) and even to slow down primary aging, thus extending the maximum lifespan an individual could hope for. In addition, populations which endured food shortages are known to have lived longer and healthier lives. The Okinawan example is, once again, of great relevance. This population had an impoverished diet during world war II which, combined with a naturally calorie restricted diet, has made it possible for individuals who were adult when the war broke to be alive today. Although genetic factors may also be in play, the fact younger Okinawans who opted for an approximation to a Western diet are facing much lower life expectancy is a strong indicator calorie restriction was at least partly responsible for the beneficial effects observed.
Nevertheless, there are some hazards to this approach. Calorie restriction is not suitable for children and teenagers, who are in a particular phase of development which requires large energy intake. There is risk of stunted growth and cognitive dysfunction. On the other end of the spectrum, the fact that calorie restriction is correlated with moderate loss of bone and muscle mass exposes the elderly to a potentially larger danger of bone fractures and loss of mobility. Moreover, even on healthy adults this is a strategy which requires significant attention, as particular care is needed to ensure the nutritional needs are consistently met and the energy intake is not too low, since such behaviour effectively consists of starvation. This is very undesirable because it is the percursor of a plethora of metabolic changes leading up to further muscle mass loss as well as hormonal imbalance and increased cellular stress levels, therefore cancelling out all the positive effects of calorie restriction.
Just for trivia, this is how I implemented the SOPA protest page yesterday.
I've been reading a little bit lately about robots. It's amazing how fast robotics has advanced in the last ten years. On the one hand we have several million robots doing useful tasks in people's homes. I'm talking of course about the Roomba.
Cryptography studies how to process data to transmit it securely, even if someone access the information in transit. For thousands of years cryptography has been a key military technology. For example, Julius Caesar used a simple encryption technique to communicate with his generals. Starting from a message text, the method replaces a letter for another letter in the alphabet that comes after one or several positions. For example, if the secret message is:
HI THIS IS A SECRET MESSAGE
To encrypt, we can replace each letter with the next letter in the alphabet H->I, I->J and so on:
IJ UIJT JT B TFDSFU NFTTBHF
To decrypt, replace with the previous letter, I->H, J->I, etc.:
HI THIS IS A SECRET MESSAGE
The reason to use encryption is obvious. Imagine yourself two thousand years ago. There is no telephone, internet, radio or anything similar. You are trying to attack an enemy army and in order to do that, you have split your forces into two, trying to enclose the enemy and force them to surrender. Now, you need to synchronize with the other side of the army so that you attack at the same time. But, if you simply send a soldier across with a message like Attack at dawn you have the risk that the soldier will be caught by the enemy army while trying to reach across. If the enemy is able to read this message they could as well maneuver during the night to escape the attack.
Here is where cryptography comes into play. If instead of sending a message like Attack at dawn you send an encrypted message, for example: BUUBDL BU EBXO now it's not obvious what the message means. Using a code secure enough so that only you and the recipient of the message are able to understand it, means that you don't need to worry about the enemy reading the message. For example, you could send three soldiers across different paths, and even if the enemy captures one of them, the attack could proceed as planned.
One of the most famous cryptographic mechanisms in history is the system used by German troops during World War II, the Enigma. Enigma is a family of machines that encrypt and decrypt messages based on a complex set of electric and mechanical components.
The relevance of the Enigma comes from the fact that it provided encryption that was vastly superior to most previous systems. It allowed the U-Boat submarines from the Third Reich to attack allied ships without any kind of warning. The Enigma encryption was broken by allied cryptanalysts. It is often said that this achievement hastened the end of the European war by two years.
Recently I had the chance to see some of these Enigma machines in a visit to Germany. They have some in display in the Deutsches Museum in Munich. I enjoyed the museum very much, and I highly recommend it. If you are ever near Munich, the Deutsches Museum is an obligated visit.
Google just announced that App Engine is going to be out of preview soon. And there is a new pricing model as part of the changes. So I decided to take a look at the resource usage of this blog and found out that the RSS feed is the most expensive request.
Human interest in the possibility of rejuvenation begins in ancient times. Around 200BC the Chinese emperor Qin Shi Huang became obsessed with his own mortality and sent the famous alchemist Xu Fu to find the Peng Lai islands (where immortal beings were believed to live) and return with the elixir of life.
Starting in the Middle Ages, European alchemists began a quest for a substance that was not only able to transform metal into gold, but also rejuvenate whoever held it: the philosopher's stone. These myths have reached the present day, and feature in works such as J. K. Rowling's (hugely successful) first Harry Potter novel.
Such contemporary references indicate we are still as fascinated by the myth as our ancestors, but we might be evolving to a scenario where what was once transcendental and restricted to the realm of the imagination is likely to become very much real and palpable. In part thanks to the work of Dr. Aubre de Grey and SENS.
Aubrey de Grey
Aubre de Grey is one of the most prominent faces of the longevity movement, and somewhat of a celebrity within scientific circles. Although he came from a computer science background, Dr. de Grey's interest in aging research was already well developed as early as 1999, when he published a book analyzing the role of mitochondria in aging, a book which granted him his Cambridge PhD, even though he had not enrolled for doctoral studies. This interest in aging research quickly became focused on regenerative medicine (or biogerontology) and in the early years of the new millennium several conferences of like-minded individuals paved the way to a plan to cure aging, which they called SENS.
SENS is an acronym for Strategies for Engineered Negligible Senescence. Despite the daunting name, the ultimate goal of this approach is simply to reach a level of technological advancement where we have such knowledge and control over the human body's biological machinery that we are able to diagnose and repair whatever goes wrong. Although, admittedly, this kind of development is bound to be decades or even centuries away, that does not mean people alive today might not see their life extended. As Dr. de Grey elegantly explains in this TED talk (included below), we don't need to solve the entire aging problem within a small time frame, but we will extend our lifespan in successive increments as research progresses and we uncover new ways to rejuvenate our bodies. Of course, in the time between discoveries we will continue to age, but as long as the speed at which new developments reach the market is greater than the rate at which biological damage takes place, we will have attained actuarial escape velocity and, consequently, the possibility to live for a very long time, and eventually immortality.
How SENS will help us live longer
In Ending Aging (a very engaging and surprisingly easy to read book), Dr. de Grey explains what he considers to be the seven factors behind aging and the SENS approaches designed to tackle them. Very briefly, these are:
- RepleniSENS - Cellular loss or atrophy
- OncoSENS - Mutations that lead to cancer and changes in the proteins that are around DNA
- ApoptoSENS - Cells which can no longer divide but refuse to die
- MitoSENS - Mutations in mitochondria
- LysoSENS - Junk that gets accumulated inside the cells
- AmyloSENS - Junk that gets accumulated outside the cells
- GlycoSENS - Random links that cells make and cause tissue to lose its elasticity
Even if the problems have been identified, we are still not at a point where we can make great strides in all areas. What SENS has been doing, however, is a number of strategic advances in areas which have great relevance now and whose potential benefits are enormous, for example:
RepleniSENS is one of those areas. The program seeks to solve the problem created by cells which divide slower than they die. This cellular behavior is behind many of the age-related pathologies, including loss of muscle strength (due simply to the decrease of the number of muscle cells) or Parkinson's disease. However, a group of German researchers working under the SENS umbrella discovered a way to administer stem cells to rats' brains in a non-invasive fashion through the nose. The rats, which exhibited symptoms of Parkinson's, showed great improvement in mobility after receiving the treatment.
Another very exciting field is the one under AmyloSENS. This approach intends to (literally) clean up the junk that accumulates outside the cells either by stimulating the immune system to find and eat it or by introducing enzymes (the agents that do the eating) directly into the body. Dr. Houk and his research team have been undertaking the Herculean task of using computer simulation to design enzymes from scratch, so they can be very effective at removing each different type of accumulated junk.
Even today, the outlook for the SENS project is not clear. In November, a group of 28 biogerontologists released a response to a paper by de Grey accusing him of being overly optimistic by claiming that each one of the specific proposals that comprise the SENS agenda is exceptionally optimistic, and went as far as stating that a program as speculative as SENS did not deserve the respect of the scientific community. Previously, de Grey sparked the controversy with a paper that he wrote in the MIT Technology review MIT Technology review offering a reward to whoever could prove that the idea of SENS was so preposterous that it was not even worthy of scholarly debate. Although 5 submissions were received, independent juries analyzed them and concluded they did not provide compelling evidence to warrant the dismissal of the SENS approach, although they recognized the speculative nature of the programme.
Other research projects
It could be said that other scientists are taking the research step-by-step, whereas SENS is looking at what lies ahead, but the immediate research concerns are not conceptually different. In fact, much exciting research in biogerontology is being done around the world. For instance, Harvard researchers took mice whose telomerase enzyme was shut down and consequently developed symptoms of aging very soon (having a very short life-span) and reactivated the enzyme. Almost instantly, the mice became healthy, with recovery being almost total. These are encouraging results not only because they indicate rehabilitation is likely to be possible even if treatment starts in adulthood, but also because it offers great promise in treating accelerated aging diseases like progeria. Similarly, a collaboration between 3 American universities uncovered that rapamycin, a drug that has been used to prevent organ rejection and to treat tumors, was able to extend the life-span of mice between 5 and 16%. What was most surprising about this result, however, is that the effect was achieved with middle-aged mice. They started administering the drug to mice at an age equivalent to 60 human years which leads credence to Dr. de Grey's belief we might yet live to see significant life-extension possibilities available.
The ethical debate on immortality
Part of the reason why SENS became so controversial recently was the whole new ethical debate it brought about immortality (or at least a much longer life) was no longer a theoretical concept, but it was possible to envision how it might become real. From one side of the barricade, individuals against this type of life-extension claimed death was natural and it would be a corruption of the natural order of things (including evolution) to thwart death. Moreover, they were concerned that social inequalities might become more pronounced as these technologies would be used by rich people in detriment of the poorer classes. On the other hand, transhumanists see nothing of natural in dying (in fact, they go as far as considering death an abomination) and find it unethical not to do anything in our power to fight it. They also argue social inequalities would not be an issue as society would adjust to the new paradigm as we have adjusted in the past.
Regardless of where you stand in this debate, one thing appears clear research on the matter, either cautiously or overtly optimistic, is happening and we are finally starting to get a glimpse of how the extremely complex machinery within our bodies works. Whether that research will be applied only time will tell but, who knows, some of us might live to celebrate the year 3000 :)
I figured out how to add authorship markup in the blog! There is a nice tutorial here, and complete documentation in the official Webmaster Tools authorship help page. But it basically comes down to this: There are two options, with 2 or 3 links.
Just wanted to leave a note on two new cool gadgets that I found online.
I read a few days ago an interesting post about what are the best fonts for programmers (monospaced fonts) at Hivelogic. And I decided to try out one of the fonts, Inconsolata. Here you have a screenshot of emacs with it.
Google+ is finally here! Google+ is the new social network from Google. It has a lot of cool features that make it better than anything else out there, like for example, the hangouts, which are like Skype, but with many friends at the same time.
Google just made the +1 button available for websites. The +1 button is a gadget that allows people to recommend content on the web.
Ive been a long time user of Google Reader. It worked great for me until a few weeks ago, when I started noticing it becoming slower. Also, I realized that many of the feeds that I frequently read were updated less frequently that I wanted. And it will only keep unread posts for up to 30 days. Anyway, my biggest issue with Reader is that its a web based RSS aggregator. Which means that it can be accessed from anywhere. Which really means that I may spend precious time reading feeds while I should be doing more useful stuff (like working...).
The Riemann Zeta Function
In the late 17th century it was known that the harmonic series is divergent, as it was proved by Pietro Mengoli, Johann Bernoulli and Jakob Bernoulli:
I decided to read again Transcend, and this time I took notes. Here are a few tips, in very synthesized form, to have better health and ensure greater longevity.
Complex Analysis is the branch of mathematics that studies functions of complex numbers. These numbers are those given by a + bi, where i is the imaginary unit, the square root of -1. We can think of complex numbers as points in a plane, where the x coordinate indicates the real component and the y coordinate indicates the imaginary component.
There are several ways to create fault tolerant systems. One of the most common is simply to duplicate the system. For example in a web application stack, we could have a master database and a slave database, which contain the same duplicated data. Also two web servers and a load balancing system that splits the load among the servers. In case of a hardware failure in a web server or a database the remaining server may be able to handle all the load while the broken one is being repaired. Replication of data and redundancy of servers is one of the reasons that some sites are highly available.
Recently I have been reading about the best way to design a graph / visualization / infographic to express a particular message. Some cases are easier than others. To show distribution of a total into parts one chart that works well is the Pie Chart. Take a look at this example:
This one is going to be a small post. A friend of mine told me about the Facebook Like buttons. One can put them in a site or in a blog post, and people can click on it to indicate that they like that item. Then the blog post or the site will appear in the Facebook homepage of that person. I checked it out and its actually pretty easy.
This one if off topic, but I couldn't resist posting it. If you have traveled by air recently you know about the porno-scanners. The TSA is forcing everyone to pass through the scanner or be subject to a thorough pat-down. So they will either watch you naked or touch all your body, including your private parts. And this includes you, your wife, your children and your grandma.
Google recently launched a new promotion for Webmaster Central and Webmaster Tools, which are undoubtedly the most important resources that the webmasters of the entire world have to optimize their sites for search (Disclaimer: I work at Webmaster Tools so Im kind of slightly biased).
During the past week shocking news have stormed through the world of Theoretical Computer Science. A researcher from HP Labs, Vinay Deolalikar claimed that he had a proof that P NP.
The folks at Zero Hedge published a very interesting post about high frequency trading and market manipulation. I am not going to discuss economy or finance now, but there is something about that post that is quite shocking. The images which show the prices and volumes of the orders routed to the market have a certain aesthetic appeal.
I just watched this fascinating talk from Murray Gell-Mann. The core idea of the talk is that in Physics, as in so many other areas of Science and Mathematics, incredibly complex ideas can be expressed in a simple and concise way. This is a remarkable property of the universe in which we live, and in that fact there is an amazing beauty.
Last week I attended Edward Tufte's course on data visualization here in Seattle. For those who don't know him, Tufte is one of the world's top experts on information visualization. Here is a short description, from his website:
A few weeks back I had a conversation with a friend about different places in the US where she was considering moving. And one of the factors was the dating scene in each one of those places. This brought to my memory a graph that probably many of you have already seen:
This quarter I am leading a study group in Machine Learning at Google's Kirkland Office. And while I was looking for datasets and resources I found Andrew Ng's course in Machine Learning at Stanford. All the lectures are available online at YouTube. You can find the links in the Stanford Engineering Everywhere Machine Learning course page.
Just a quick pointer to a book that I am reading right now, Quantitative Ponzinomics, an essential guide to understand what is going on currently in the financial markets around the world.
Ok, it's not a real book, but you should really check out the source, the financial blog Zero Hedge. And in order to keep this blog on-topic, here is an interesting link about High Frequency Trading, which is an automated procedure to make financial transactions using computer algorithms to get an advantage over other investors.
Over the last few decades hundreds of companies, thousands of jobs and billions of dollars of real wealth were created by startups with the support of angel investors. The possibility of a small company to obtain seed funding with little more than an idea is indeed one of the most important wealth creation engines of America. Now this possibility, this engine, is at stake.
Infographics, or information graphics are visual representations of data. In a good visualization or representation of a data set, the author expresses an idea that is deeper that the data itself. A good visualization conveys a message that is clear and helps to extract conclusions, but also a message that is precise and based on the data, without transforming or manipulating the data in dishonest ways.
SEO stands for Search Engine Optimization, and is the process of improving a website's structure and content in order to make it easy for search engines to gather the pages and display them in search results in the best position possible.
Mathematical research is traditionally seen as a one-man job. To quote Jean Dieudonn in The Music of Reason:
Google recently released a new set of tools for graphics and interactive visualizations called Google Chart Tools. Google Chart Tools replaces the previous Charts API (for static images) and Visualization API (for dynamic graphics). And it combines both APIs within a single framework. Here is a link to the official announcement.
Over the last few weeks this blog has changed dramatically. It looks pretty much the same as when it started but under the covers the code of the blogging platform, Nounoublog is very different. I am going to talk about three of the features that I have been working on lately:
My brother David is a film director. He has been making short film for a few years, he has even won a few prizes. Most of his work is at tpmpictures.com. Today I just wanted to show his last piece of work, a science fiction short about the end of the world. The short is in Spanish but with English subtitles.
A couple of days ago I started reading TRANSCEND, the new book from Ray Kurzweil and Terry Grossman. The book starts from the principle that our knowledge of medicine and biology is increasing to a point where we can start to control effectively how fast our own bodies age. And even more important the amount of knowledge that we gather is increasing over time. If the trend continues we may reach a point where we can effectively reverse engineer our bodies in order to avoid aging.
This Monday I published my article on MapReduce for integer factorization in arXiv. The article is essentially the same that can be downloaded in the research section of this site. So if you have already checked it out, you won't find anything new. However I am very excited because it is my first addition to arXiv.
Recently I published the code of MapReduce for Integer Factorization. It is available under the Apache 2.0 License in Google Code. It includes everything necessary to run in Apache Hadoop, as well as the numerical libraries used. It has no dependencies apart from the last version of Hadoop.
If you have never made a web application it may seem daunting. There are hundreds of alternative technologies and frameworks out there. And web apps development is quite different from client applications, which is what most developers are used to.
Visualizations are simply ways of representing data. But if they are good, they can bring us deep insights, that go well beyond what is possible to understand by simply looking at the raw data.
Hello everybody. This is the first post in my new blog. This is not your common Wordpress or Blogger blog. It runs on a custom blogging platform made from scratch, on top of Google App Engine. Soon I will add a couple of posts about how it’s done, and I will release the code of the platform.
Here are some of the projects that I worked on over the last few years:
FinanceAI is an open source project with the goal of providing advanced Artificial Intelligence, Statistical and Mathematical tools for amateur and sophisticated investors. The purpose was to develop a complete algorithmic trading platform with comprehensive AI and Quantitative Finance libraries. It would also provide high performance algorithms. I started this project in early 2008, but so far it didn’t get past the first version, mostly because of lack of time.