Google, Yahoo and others are taking the traditional database system and breaking it into pieces. Google has their own set of propriety database system components. Yahoo is working with the Hadoop Open Source project to make their system available to everyone. I came to this conclusion while doing research for my talk on "Models and Patterns for Concurrency" for the SDForum SAM SIG.
In this post I will talk about what is happening, why it is happening and at the end try to draw some conclusions about future directions for database systems. Note, I am using Google as an example here because their system is described in a set of widely accessible academic papers. Yahoo and many other large scale web sites have adopted a similar approach through use of Hadoop and other Open Source projects.
A traditional database system is a server. It takes care of persistent data storage, metadata management for the stored data, transaction management and querying the data, which includes aggregation. Google has developed its own set of applications which support these same functions, except instead of wrapping them into a single entity as a database server, they have been developed as a set of application programs that build on one another.
The are several reasons for Google developing their own database system. Firstly, they are dealing with managing and processing huge amounts of data. Conventional database systems struggle when the data gets really large. In particular the transaction model that underlies database operation starts to break down. This topic is worth a separate post of its own.
Secondly they their computing system is a distributed system built from thousands of commodity computer systems. Conventional database systems are not designed or tuned to run on this type of hardware. One issue is that at this scale the hardware cannot be assumed to be reliable and the database system has to be designed to work around the unreliable hardware. A final issue is that the cost of software licenses for running a conventional database system on the Google hardware would be prohibitive.
The Google internal application look like this. A the bottom is Chubby, a lock service that also provides reliable storage for small amounts of data. The Google File System provides file data storage in a distributed system of thousands of computers with local disks. It uses Chubby to ensure that there is a single master in the face of system failures. Bigtable is a system for storing and accessing structured data. While it is not exactly relational, it is comparable to storing data in a single large relational database table. Bigtable stores its data in the Google File System and uses Chubby for several purposes including metadata storage and to ensure atomicity of certain operations.
Finally Map Reduce is a generalized aggregation engine (and here I mean aggregation in the technical database sense). It uses the Google File System. Map Reduce is surprisingly closely related to database aggregation as found in the SQL language although it is not usually described in that way. I will discuss this in another post. In the mean time, it is interesting to note that Map Reduce has been subject to a rather intemperate attack by database luminaries David DeWitt and Michael Stonebreaker.
In total, these four applications: Chubby, Google File System, Bigtable and Map Reduce provide the capabilities of a database system. In practice there are some differences. The user writes program in a language like C++ that integrated the capabilities of these components as they need them. They do not need to use all the components. For example, Google can calculate the page rank for each page on the web as a series of 6 Map Reduce steps none of which necessarily uses Bigtable.
The concept of a Database System was invented in the late 60's by the CODASYL committee, shortly after their achievement of inventing the COBOL programming language. The Relational model and Transactions came later, however the concept of a server system that owns and manages data and much of the terminology originated with CODASYL. Since then, the world has changed.
Nowadays databases are often hidden behind frameworks such as Hibernate or Ruby on Rails that try to paper over the impedance mismatch between the database model on one side and an object oriented world looking for persistence on the other. These are mostly low end systems. At the other end of scale are the huge data management problems of Google, Yahoo and other web sites. New companies with new visions of database systems to meet these challenges are emerging. It is an exciting time.
Saturday, October 25, 2008
Saturday, October 11, 2008
Its Called Risk, Have You Heard Of It?
Senator Phil Gramm famously called us a "nation of whiners" and he may be right. (Note, while I try to keep this blog about technology, the financial system seems to be so badly broken it is worthy of a comment or two.) I recently ran across a blog post on a financial site called "Our Timid Government Is Killing Us" by Michael Kao, CEO of Akanthos Capital Management. In it he complains about 4 things that the Government has not done to help resolve the financial crisis. I want to concentrate on one of there here. "Problem No. 2: Lehman's bankruptcy has severely eroded confidence between counterparties."
The problem is this. Over the last few weeks, financial institutions have become unwilling to trust one another and with good cause. The issue is Credit Default Swaps. This is a 60 Trillion dollar market (that is Trillion with a capital T) where financial institutions like banks and hedge funds (the parties) buy and sell insurance policies on bonds. The "This American Life" radio program and Podcast has very good and understandable explanation of the market and how it came to be.
There are two important things to understand about the credit default swap market. Firstly, it is completely unregulated. Senator Phil Gramm tacked a clause to keep the market unregulated to an appropriations bill in 2000 that was approved by 95 votes to 0 in the Senate. Secondly, the market is not transparent, that is the various parties to the market do not know what any other players position is. Note that these two features are the way the parties in the market wanted it. There has been great outcry about reducing financial regulations in the last few years.
Lack of transparency was not a problem until Lehman Brothers went bankrupt. They were a big player in the credit default swap market. Now all their credit default swap insurance policies are frozen by their bankruptcy. Anyone who sold a credit default swap policy and then laid off the bet by buying an equivalent credit default swap from Lehman Brothers is now on the hook to pay off the insurance policy on the bond without the compensation of being able to get Lehman Brothers to make good on their policy.
The lack of transparency means that nobody knows for sure about anyone else in the market. That is that anyone could go bankrupt tomorrow because they have bought credit default swaps from a bankrupt company like Lehman Brothers and they cannot make good on their promise of a credit default swaps that they have sold. Already AIG has needed a huge injection of government money to stay afloat, and others may be suffering as well. But no one knows what positions anyone else holds. So everyone is conserving their cash not lending it out to anyone else so that they will not lose it if the other party goes bankrupt. Thus are the credit markets constipated.
A final problem is that, because the market is unregulated, there are no capital requirements to back up a bet. I can sell a credit default swap insurance policy based on my good name. I immediately get a large sum of money which I can register as a profit. It is only later that I have to worry about a problem with the bond that I have insured defaulting (what are the chances of that?) This is how the market got to be 60 Trillion dollars in size.
The underlying issue is this. There is a large risk in trading in unregulated markets. The risk is made larger if the market is not transparent, because if one of the parties to the market goes bust nobody knows what their position is worth. These risks were not recognized in the credit default swap market and policies were sold at far too low a price to recognize these risks. If the market were regulated, like other markets are, these risks would not be there and the market could deal with usual events like a bankruptcy of a player.
Finally there is a risk to the nation in allowing an unregulated market to balloon to the size that the credit default swap market has. Bankruptcies happen all the time. the fact that the bankruptcy of a player has caused the entire financial marketplace to go into a swoon is bad for the nation. The players in the credit default swap market asked for an unregulated market and they got what they asked for. Now the risk of having an unregulated market has shown itself and as Senator Gramm tells them they should deal with it and stop whining.
I am not an apologist, I am a technologist who is interested in how things work.
The problem is this. Over the last few weeks, financial institutions have become unwilling to trust one another and with good cause. The issue is Credit Default Swaps. This is a 60 Trillion dollar market (that is Trillion with a capital T) where financial institutions like banks and hedge funds (the parties) buy and sell insurance policies on bonds. The "This American Life" radio program and Podcast has very good and understandable explanation of the market and how it came to be.
There are two important things to understand about the credit default swap market. Firstly, it is completely unregulated. Senator Phil Gramm tacked a clause to keep the market unregulated to an appropriations bill in 2000 that was approved by 95 votes to 0 in the Senate. Secondly, the market is not transparent, that is the various parties to the market do not know what any other players position is. Note that these two features are the way the parties in the market wanted it. There has been great outcry about reducing financial regulations in the last few years.
Lack of transparency was not a problem until Lehman Brothers went bankrupt. They were a big player in the credit default swap market. Now all their credit default swap insurance policies are frozen by their bankruptcy. Anyone who sold a credit default swap policy and then laid off the bet by buying an equivalent credit default swap from Lehman Brothers is now on the hook to pay off the insurance policy on the bond without the compensation of being able to get Lehman Brothers to make good on their policy.
The lack of transparency means that nobody knows for sure about anyone else in the market. That is that anyone could go bankrupt tomorrow because they have bought credit default swaps from a bankrupt company like Lehman Brothers and they cannot make good on their promise of a credit default swaps that they have sold. Already AIG has needed a huge injection of government money to stay afloat, and others may be suffering as well. But no one knows what positions anyone else holds. So everyone is conserving their cash not lending it out to anyone else so that they will not lose it if the other party goes bankrupt. Thus are the credit markets constipated.
A final problem is that, because the market is unregulated, there are no capital requirements to back up a bet. I can sell a credit default swap insurance policy based on my good name. I immediately get a large sum of money which I can register as a profit. It is only later that I have to worry about a problem with the bond that I have insured defaulting (what are the chances of that?) This is how the market got to be 60 Trillion dollars in size.
The underlying issue is this. There is a large risk in trading in unregulated markets. The risk is made larger if the market is not transparent, because if one of the parties to the market goes bust nobody knows what their position is worth. These risks were not recognized in the credit default swap market and policies were sold at far too low a price to recognize these risks. If the market were regulated, like other markets are, these risks would not be there and the market could deal with usual events like a bankruptcy of a player.
Finally there is a risk to the nation in allowing an unregulated market to balloon to the size that the credit default swap market has. Bankruptcies happen all the time. the fact that the bankruptcy of a player has caused the entire financial marketplace to go into a swoon is bad for the nation. The players in the credit default swap market asked for an unregulated market and they got what they asked for. Now the risk of having an unregulated market has shown itself and as Senator Gramm tells them they should deal with it and stop whining.
I am not an apologist, I am a technologist who is interested in how things work.
Thursday, October 02, 2008
Articulate UML Modeling
Last week, Leon Starr spoke to the SDForum SAM SIG on "Articulate UML Modeling". Leon is an avid modeler and has been using UML for modeling software systems since it was first defined. He believes in building executable models and I applaud him for that. The very act of making something executable ensures that it is in some sense complete and free from many definitional errors. Executing the model allows it to be tested.
There are several advantages to building models rather than programs. A big part of many project is extracting requirements. Unlike a program, a model can describe requirements in a way that a non-technical user can understand and appreciate, so the user can provide feedback. Another advantage of a model is that is does not arbitrarily constrain the order in which things are done. Essentially, a model is asynchronous and captures opportunities for concurrency in its implementation. This struck a chord with me as I am going to speak to the SAM SIG in October on "Models and Patterns for Concurrency".
The other part of the talk that interested me was Leon's attack on building models as controllers. For example, he gave the example of a laser cutting machine. A common way of modeling this is the laser cutter controller that interprets patterns. He prefers to see this modeled as patterns that describe how they are cut by the laser cutter. Leon's experience is with modeling software to manage physical systems like the air traffic controller example that he used to illustrate his talk. His approach is certainly useful for the understanding and analysis of physical systems, however I have seen the problem argued both ways. It is worth a separate post on the issue.
There are several advantages to building models rather than programs. A big part of many project is extracting requirements. Unlike a program, a model can describe requirements in a way that a non-technical user can understand and appreciate, so the user can provide feedback. Another advantage of a model is that is does not arbitrarily constrain the order in which things are done. Essentially, a model is asynchronous and captures opportunities for concurrency in its implementation. This struck a chord with me as I am going to speak to the SAM SIG in October on "Models and Patterns for Concurrency".
The other part of the talk that interested me was Leon's attack on building models as controllers. For example, he gave the example of a laser cutting machine. A common way of modeling this is the laser cutter controller that interprets patterns. He prefers to see this modeled as patterns that describe how they are cut by the laser cutter. Leon's experience is with modeling software to manage physical systems like the air traffic controller example that he used to illustrate his talk. His approach is certainly useful for the understanding and analysis of physical systems, however I have seen the problem argued both ways. It is worth a separate post on the issue.
Monday, September 29, 2008
42 Revisited
Last week TechCrunch had a post on the State of The Blogosphere: The More You Post, The Higher You Rank. One statistic is that the top 100 bloggers post on average 310 times a month, which sounds quite exhausting. As you know, I post 42 times a year. I am going to promise to my faithful reader that I will stick to my pace. You will not get an unreadable avalanche of overlapping verbiage from this blog.
If I have not posted much recently, it is because I have spent a lot of time reading blog posts on the financial crisis. It is very entertaining to see these extrordinary events unfold around us. Who would have thought that George W. Bush will be known to future generations as the President who nationalized the American financial services industry?
If I have not posted much recently, it is because I have spent a lot of time reading blog posts on the financial crisis. It is very entertaining to see these extrordinary events unfold around us. Who would have thought that George W. Bush will be known to future generations as the President who nationalized the American financial services industry?
Wednesday, September 17, 2008
SaaS Data Integration
Data integration is the problem of gathering data, perhaps from many different application for the purpose of doing some analysis of the data as a whole. Mike Pittaro, Co-Founder of SnapLogic spoke to the SDForum Business Intelligence SIG September meeting on "Enhancing SaaS Applications Through Data Integration with SnapLogic".
The big players in data integration are Informatica and Ascential (now IBM Information Integration) who sell large, expensive and complex products. Because of the cost, these products are often not used, particularly for one off projects which are common. Mike helped found SnapLogic in 2005 to bring a new perspective to data integration. SnapLogic is an open source framework and therefore both affordable and extensible by its users.
He showed us the complexity of data integration. It involves dealing with many different access protocols, multiple ways of getting the data and each type of data has its own metadata format to describe the data. This he contrasted with the World Wide Web where huge amounts of data are pulled back and forth every day, without interoperability problems. There are almost 200 million web sites, and billions of users, yet World Wide Web is completely decentralized, with heterogeneous model that allows for different operating system, servers, client software applications and frameworks, and yet they are all compatible and interoperable.
The World Wide Web is based on open standards and protocols and an architectural principal called REST, which stands for REpresentational State Transfer. REST plays with data resources, in standardized representations and each resource identified by a unique identifier like a URL.
SnapLogic builds on this by turning data sources into standard web resources. With SnapLogic you configure a server to extracts data from a datasource like a file or database and transform the data into the form you want. The server presents the datasource as a standard web resource with a URL. These servers are the blocks for building a data integration application.
The big players in data integration are Informatica and Ascential (now IBM Information Integration) who sell large, expensive and complex products. Because of the cost, these products are often not used, particularly for one off projects which are common. Mike helped found SnapLogic in 2005 to bring a new perspective to data integration. SnapLogic is an open source framework and therefore both affordable and extensible by its users.
He showed us the complexity of data integration. It involves dealing with many different access protocols, multiple ways of getting the data and each type of data has its own metadata format to describe the data. This he contrasted with the World Wide Web where huge amounts of data are pulled back and forth every day, without interoperability problems. There are almost 200 million web sites, and billions of users, yet World Wide Web is completely decentralized, with heterogeneous model that allows for different operating system, servers, client software applications and frameworks, and yet they are all compatible and interoperable.
The World Wide Web is based on open standards and protocols and an architectural principal called REST, which stands for REpresentational State Transfer. REST plays with data resources, in standardized representations and each resource identified by a unique identifier like a URL.
SnapLogic builds on this by turning data sources into standard web resources. With SnapLogic you configure a server to extracts data from a datasource like a file or database and transform the data into the form you want. The server presents the datasource as a standard web resource with a URL. These servers are the blocks for building a data integration application.
Thursday, September 04, 2008
Chrome
On Tuesday, Google announced their new browser Chrome. Although it has generated huge discussions in various forums and an astonishing adoption rate, I am not going to rush to use it. In fact, I think I will wait until it is out of beta before considering whether to adopt it. That should give me many years before I have to even think about making a change!
Wednesday, September 03, 2008
A Tale of Two Search Engines
At the SDForum Software Architecture and Modeling (SAM) SIG last week, John D. Mitchel, Mad Scientist at MarkMail and previously Chief Architect of Krugle talked about the architectures of the search engines that he has built for these two companies.
Krugle is a search engine for code and all related programming artifacts. The public engine indexes all the open source software repositories on the web. This system was built a couple of years ago with cheap of the shelf commodity hardware, open source software and Network Attached Storage (NAS). In total it has about 150 computer systems in its clusters. The major software components are Lucene (search engine), Nutch (web crawling and etc.) and Hadoop (distributed file system and map-reduce). These are all Open Source projects written in Java and sponsored by the Apache Software Foundation. Krugle sells an enterprise edition that can index and make available all source code in an enterprise.
MarkMail is a search engine for email. It indexes all public mailing lists and is a technology demonstrator for the MarkLogic XML Content Server. MarkMail is built with newer hardware that is more capable. It uses Storage Area Network (SAN) for storage which offers higher performance at a greater cost than NAS. The MarkMail search system is built on about 60 computer systems in its clusters.
Krugle is a search engine for code and all related programming artifacts. The public engine indexes all the open source software repositories on the web. This system was built a couple of years ago with cheap of the shelf commodity hardware, open source software and Network Attached Storage (NAS). In total it has about 150 computer systems in its clusters. The major software components are Lucene (search engine), Nutch (web crawling and etc.) and Hadoop (distributed file system and map-reduce). These are all Open Source projects written in Java and sponsored by the Apache Software Foundation. Krugle sells an enterprise edition that can index and make available all source code in an enterprise.
MarkMail is a search engine for email. It indexes all public mailing lists and is a technology demonstrator for the MarkLogic XML Content Server. MarkMail is built with newer hardware that is more capable. It uses Storage Area Network (SAN) for storage which offers higher performance at a greater cost than NAS. The MarkMail search system is built on about 60 computer systems in its clusters.
Saturday, August 16, 2008
Windows Woes
For years it seemed like a good idea, Microsoft produced the software and many vendors sold compatible hardware. Competition kept the hardware innovation flowing and prices low. Then Microsoft turned into a big bloated monopoly that could not create a decent product if it tried. Moreover, Microsoft is not really in control, it itself is hostage to other interests. The result is a horrible user experience. Here are a couple of my recent experiences.
A few months ago I bought a new video card so that it would use the digital input to the monitor. Installing the card was a breeze and the digital input makes the monitor noticeably sharper. The only problem was that the sound had stopped working. After a couple of hours scratching my head and vigorous Googling, the problem turns out to have been caused by Hollywood.
The connection between a computer and its display uses HDMI, a digital interconnect standard that can transmit both video and audio. This allows a PC to connect to a digital television as well as a simple display. It also allows the video and audio content to be encrypted so that you cannot steal it from your own computer. This was mandated by Hollywood and Microsoft meekly acquiesced to it so that they could provide media center software that would display Hollywood movies in high definition.
So after the video card installation, Windows software assumed that I was going to use the digital audio output on the video card and ignored all other audio output devices. This even although my display does not have any speakers. I had to go into the BIOS and change some low level settings for sound so that Windows would allow me to select the sound settings that I had been using before installing the video card. Any time you have to go into the BIOS to change settings, the user experience loses.
More recently my brother and family came to visit during a tour of California. He wanted to unload all the pictures on his cameras flash card and write them to a CD as the flash card was full. I suggested the easy way out, visit Fry's Electronics and buy another flash card, but that deemed more trouble. In practice it would have been much easier.
We downloaded the flash card to my PC. The first difficulty is that you are presented with a list of 6 competing programs that want to download your pictures. Which one should I use? I know that in practice they are all going to put the pictures in some ridiculous place where you can never find them again (that is the subject of another tirade). I chose the first in the list which happened to be compatible with the brand of digital camera.
The next problem came when we went into Windows Explorer so that we could drag the pictures to the CD ROM folder. Every time we went into the folder where the pictures were, Explorer exited saying that it had an unexpected fault. I knew exactly what the problem was because I had seen it before. There were some movie files taken with the digital camera, and Windows has problem with these movie (.avi) files. For some reason, Explorer tries to open every file in a folder when it enters the folder, even although I set it to just list the files and not display thumbnails.
The fix was to open a DOS window, navigate to the folder with the files and rename them so that Windows would not think they were media files. I added the extension .tmp to each .avi file by laborious typing. Then it was possible to do the intuitive drag and and drop with Explorer to make a CD ROM. Any time you have to resort to using a DOS window to do a straightforward function in Windows, usability has gone out the window.
I could go on (as I have in the past), there have been more problems, however with each problem the Apple alternative looks better. Apple is by no means perfect, however the Apple OS is built on a better foundation and the innovations that it makes when it comes out with a new version are both useful and innovative.
A few months ago I bought a new video card so that it would use the digital input to the monitor. Installing the card was a breeze and the digital input makes the monitor noticeably sharper. The only problem was that the sound had stopped working. After a couple of hours scratching my head and vigorous Googling, the problem turns out to have been caused by Hollywood.
The connection between a computer and its display uses HDMI, a digital interconnect standard that can transmit both video and audio. This allows a PC to connect to a digital television as well as a simple display. It also allows the video and audio content to be encrypted so that you cannot steal it from your own computer. This was mandated by Hollywood and Microsoft meekly acquiesced to it so that they could provide media center software that would display Hollywood movies in high definition.
So after the video card installation, Windows software assumed that I was going to use the digital audio output on the video card and ignored all other audio output devices. This even although my display does not have any speakers. I had to go into the BIOS and change some low level settings for sound so that Windows would allow me to select the sound settings that I had been using before installing the video card. Any time you have to go into the BIOS to change settings, the user experience loses.
More recently my brother and family came to visit during a tour of California. He wanted to unload all the pictures on his cameras flash card and write them to a CD as the flash card was full. I suggested the easy way out, visit Fry's Electronics and buy another flash card, but that deemed more trouble. In practice it would have been much easier.
We downloaded the flash card to my PC. The first difficulty is that you are presented with a list of 6 competing programs that want to download your pictures. Which one should I use? I know that in practice they are all going to put the pictures in some ridiculous place where you can never find them again (that is the subject of another tirade). I chose the first in the list which happened to be compatible with the brand of digital camera.
The next problem came when we went into Windows Explorer so that we could drag the pictures to the CD ROM folder. Every time we went into the folder where the pictures were, Explorer exited saying that it had an unexpected fault. I knew exactly what the problem was because I had seen it before. There were some movie files taken with the digital camera, and Windows has problem with these movie (.avi) files. For some reason, Explorer tries to open every file in a folder when it enters the folder, even although I set it to just list the files and not display thumbnails.
The fix was to open a DOS window, navigate to the folder with the files and rename them so that Windows would not think they were media files. I added the extension .tmp to each .avi file by laborious typing. Then it was possible to do the intuitive drag and and drop with Explorer to make a CD ROM. Any time you have to resort to using a DOS window to do a straightforward function in Windows, usability has gone out the window.
I could go on (as I have in the past), there have been more problems, however with each problem the Apple alternative looks better. Apple is by no means perfect, however the Apple OS is built on a better foundation and the innovations that it makes when it comes out with a new version are both useful and innovative.
Thursday, July 17, 2008
A Gentle Introduction to R
We were given a gentle introduction to the R statistical programming language and its application in Business Intelligence at the July meeting of the SDForum Business Intelligence SIG. The speakers were Jim Porzac ( Senior Director of Analytics at Responsys) and Michael Driscoll (Principal at Dataspora). Jim has posted the presentation here.
R is an Open Source project that uses the GNU license. It has a growing user base with a strong support community and a user group (called UseR Group - try Googling that). There are now almost 1500 packages for the languages that supports various statistical techniques and specialized application areas. Packages include: Bayesian, Econometrics, Genetics, Machine Learning, Natural Language Processing, Pharmacokinetics, Psycometrics, which gives some idea of the range of subjects and techniques that R covers.
Jim did most of the talking, introducing the language and showing us some examples of its use. One example is his data quality package that he uses on each new dataset that he receives for analysis at Responsys. Another example showed how reporting capabilities while a third showed sophisticated graphs and plots used for customer segmentation analysis. Michael showed us how he used R to do some interesting and very practical analyzes of Baseball statistics.
The audience probed R's strength and weakness. R has the connectivity to get data for analysis from databases and other sources. R also has excellent graphing and reporting capabilities. Currently R works by reading data into memory where it is manipulated, which limits the maximum size of data set that can be analyzed to the many Gigabyte range.
One person asked for a comparison with SAS. R has the advantages of being free with an enthusiastic user base to keeps it on the cutting edge. Also R is a more coherent language than SAS, which is a collection of libraries, each of which may be very good but they do not necessarily make a whole.
Jim and Michael are starting a Bay Area chapter of the UseR Group. If you are interested, contact Jim Porzac at Responsys.
R is an Open Source project that uses the GNU license. It has a growing user base with a strong support community and a user group (called UseR Group - try Googling that). There are now almost 1500 packages for the languages that supports various statistical techniques and specialized application areas. Packages include: Bayesian, Econometrics, Genetics, Machine Learning, Natural Language Processing, Pharmacokinetics, Psycometrics, which gives some idea of the range of subjects and techniques that R covers.
Jim did most of the talking, introducing the language and showing us some examples of its use. One example is his data quality package that he uses on each new dataset that he receives for analysis at Responsys. Another example showed how reporting capabilities while a third showed sophisticated graphs and plots used for customer segmentation analysis. Michael showed us how he used R to do some interesting and very practical analyzes of Baseball statistics.
The audience probed R's strength and weakness. R has the connectivity to get data for analysis from databases and other sources. R also has excellent graphing and reporting capabilities. Currently R works by reading data into memory where it is manipulated, which limits the maximum size of data set that can be analyzed to the many Gigabyte range.
One person asked for a comparison with SAS. R has the advantages of being free with an enthusiastic user base to keeps it on the cutting edge. Also R is a more coherent language than SAS, which is a collection of libraries, each of which may be very good but they do not necessarily make a whole.
Jim and Michael are starting a Bay Area chapter of the UseR Group. If you are interested, contact Jim Porzac at Responsys.
Wednesday, July 09, 2008
Social Search
The SDForum Search SIG pulled together an A-List panel for their July meeting on Social Search. Moderator Safa Rashtchy hosted Bret Taylor of FriendFeed, Ari Steinberg of FaceBook, Jason Calacanis of Mahalo and Jeremie Miller of Wikia Search. Of the panelists, Jason Calacanis had the most to say, was arguably the most interesting and definitely the most opinionated. He also recorded the event with the camera in his MacBook Air. Vallywag has a better and more concise video excerpt of Jason in action shaded by their desire to capture controversy.
Facebook and FriendFeed are working on automated search within their social networks, while Mahalo and Wikia Search are working on improving general search by using people to curate the results. Mahalo is paying people, while Wikia Search is trying to use the Wikipedia model of free community involvement.
Most of the audience questions to the panel were about their business models and monetization. I tried to tried to get into technicalities by asking a question about Search Quality, there was a question on privacy, and one audience member argued that none of the panelists companies were doing social search as he defined it.
Facebook and FriendFeed are working on automated search within their social networks, while Mahalo and Wikia Search are working on improving general search by using people to curate the results. Mahalo is paying people, while Wikia Search is trying to use the Wikipedia model of free community involvement.
Most of the audience questions to the panel were about their business models and monetization. I tried to tried to get into technicalities by asking a question about Search Quality, there was a question on privacy, and one audience member argued that none of the panelists companies were doing social search as he defined it.
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