Welcome!

Apache Authors: Elizabeth White, Sematext Blog, Carmen Gonzalez, Pat Romanski, Yeshim Deniz

Blog Feed Post

A First Look at rxDForest()

by Joseph RIckert Last July, I blogged about rxDTree() the RevoScaleR function for building classification and regression trees on very large data sets. As I explaned then, this function is an implementation of the algorithm introduced by Ben-Haim and Yom-Tov in their 2010 paper that builds trees on histograms of data and not on the raw data itself. This algorithm is designed for parallel and distributed computing. Consequently, rxDTree() provides the best performance when it is running on a cluster: either an Microsoft HPC cluster or a Linux LSF cluster. rxDForest() (new with Revolution R Enterprise 7.0) uses rxDTree() to take the next logical step and implement a random forest type algorithm for building both classification and regression forests. Each tree of the ensemble constructed by rxDForest() is built with a bootstrap sample that uses about 2/3 of the original data. The data not used in builting a particular tree is used to make predictions with that tree. Each point of the original data set is fed through all of the trees that were built without it. The decision forest prediction for that data point is the statistical mode of the individual tree predictions. (For classification problems the prediction is a majority vote, for regression problems the prediction is the mean of the predictions.)  Only a couple of parameters need to be set to fit a decision forest. nTree specifies the number of trees to grow and  mTry spedifies the number of variables to sample as split candidates at each tree node. Of course, many more parameters can be set to control the algorithm, including the parameters that control the underlying rxDTree() algorithm. The following is a small example of the rxDForest() fucntion using the mortgage default dataset that can be downloaded from Revolution Analytic's website. Here are the first three lines of data.   creditScore houseAge yearsEmploy ccDebt year default1    615        10        5          2818 2000    02    780        34        5          3575 2000    0 3    735        12        1          3184 2000    0  The idea is to see if the variables creditScore, houseAge etc. are useful in predicting a default. The RevoScaleR R code in the file Download RxDForest  reads in the mortgage data, splits the data into a training file and a test file, uses rxDTree() to build a single tree (just to see what one looks like for this file) and plots the tree. Then rxDForest() is run against the training file to to build an ensemble model and this model run against the test file to make predictions. Finally, the code plots the ROC curve for the decision forest ensemble model. Here is what the first few nodes of the tree looks like. (The full tree is printed at the bottom of the code in the file above.) Call: rxDTree(formula = form1, data = "mdTrain", maxDepth = 5)File: C:\Users\Joe.Rickert\Documents\Revolution\RevoScaleR\mdTrain.xdf Number of valid observations: 8000290 Number of missing observations: 0 Tree representation: n= 8000290 node), split, n, deviance, yval * denotes terminal node 1) root 8000290 39472.30000 4.958445e-03 2) ccDebt< 9085.5 7840182 21402.25000 2.737309e-03 4) ccDebt< 7844 7384170 8809.46500 1.194447e-03  He is a plot of the right part of the tree drawn with RevoScaleR's creatTreeView() function that enables plot() to put the graph in your browser.     And, finally, here is the ROC curve for the decision Forest model. (The text output describing the model is also in the file containing the code.)   I plan to try rxDForest() out on a cluster with a bigger data set. When I do, I will let you know. 

Read the original blog entry...

More Stories By David Smith

David Smith is Vice President of Marketing and Community at Revolution Analytics. He has a long history with the R and statistics communities. After graduating with a degree in Statistics from the University of Adelaide, South Australia, he spent four years researching statistical methodology at Lancaster University in the United Kingdom, where he also developed a number of packages for the S-PLUS statistical modeling environment. He continued his association with S-PLUS at Insightful (now TIBCO Spotfire) overseeing the product management of S-PLUS and other statistical and data mining products.<

David smith is the co-author (with Bill Venables) of the popular tutorial manual, An Introduction to R, and one of the originating developers of the ESS: Emacs Speaks Statistics project. Today, he leads marketing for REvolution R, supports R communities worldwide, and is responsible for the Revolutions blog. Prior to joining Revolution Analytics, he served as vice president of product management at Zynchros, Inc. Follow him on twitter at @RevoDavid

@ThingsExpo Stories
With major technology companies and startups seriously embracing IoT strategies, now is the perfect time to attend @ThingsExpo in Silicon Valley. Learn what is going on, contribute to the discussions, and ensure that your enterprise is as "IoT-Ready" as it can be! Internet of @ThingsExpo, taking place Nov 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 17th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The Internet of Things (IoT) is the most profound change in personal an...
@ThingsExpo has been named the Top 5 Most Influential Internet of Things Brand by Onalytica in the ‘The Internet of Things Landscape 2015: Top 100 Individuals and Brands.' Onalytica analyzed Twitter conversations around the #IoT debate to uncover the most influential brands and individuals driving the conversation. Onalytica captured data from 56,224 users. The PageRank based methodology they use to extract influencers on a particular topic (tweets mentioning #InternetofThings or #IoT in this case) takes into account the number and quality of contextual references that a user receives.
17th Cloud Expo, taking place Nov 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud strategy. Meanwhile, 94% of enterprises are using some form of XaaS – software, platform, and infrastructure as a service.
Enterprise IoT is an exciting and chaotic space with a lot of potential to transform how the enterprise resources are managed. In his session at @ThingsExpo, Hari Srinivasan, Sr Product Manager at Cisco, will describe the challenges in enabling mass adoption of IoT, and share perspectives and insights on architectures/standards/protocols that are necessary to build a healthy ecosystem and lay the foundation to for a wide variety of exciting IoT use cases in the years to come.
Avnet, Inc. has announced that it ranked No. 4 on the InformationWeek Elite 100 – a list of the top business technology innovators in the U.S. Avnet was recognized for the development of an innovative cloud-based training system that serves as the foundation for Avnet Academy – the company’s education and training organization focused on technical training around top IT vendor technologies. The development of this system allowed Avnet to quickly expand its IT-related training capabilities around the world, while creating a new service that Avnet and its IT solution providers can offer to their...
@ThingsExpo has been named the Top 5 Most Influential M2M Brand by Onalytica in the ‘Machine to Machine: Top 100 Influencers and Brands.' Onalytica analyzed the online debate on M2M by looking at over 85,000 tweets to provide the most influential individuals and brands that drive the discussion. According to Onalytica the "analysis showed a very engaged community with a lot of interactive tweets. The M2M discussion seems to be more fragmented and driven by some of the major brands present in the M2M space. This really allows some room for influential individuals to create more high value inter...
SYS-CON Events announced today that B2Cloud, a provider of enterprise resource planning software, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. B2cloud develops the software you need. They have the ideal tools to help you work with your clients. B2Cloud’s main solutions include AGIS – ERP, CLOHC, AGIS – Invoice, and IZUM
It's time to put the "Thing" back in IoT. Whether it’s drones, robots, self-driving cars, ... There are multiple incredible examples of the power of IoT nowadays that are shadowed by announcements of yet another twist on statistics, databases, .... Sorry, I meant, Big Data(TM), tiered storage(TM), complex systems(TM), smart nations(TM), .... In his session at WebRTC Summit, Dr Alex Gouaillard, CTO and Co-Founder of Temasys, will discuss the concrete, cool, examples of IoT already happening today, and how mixing all those different sources of visual and audio input can make your life happier ...
The WebRTC Summit 2015 New York, to be held June 9-11, 2015, at the Javits Center in New York, NY, announces that its Call for Papers is open. Topics include all aspects of improving IT delivery by eliminating waste through automated business models leveraging cloud technologies. WebRTC Summit is co-located with 16th International Cloud Expo, @ThingsExpo, Big Data Expo, and DevOps Summit.
SYS-CON Events announced today that MangoApps will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY., and the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. MangoApps provides private all-in-one social intranets allowing workers to securely collaborate from anywhere in the world and from any device. Social, mobile, and easy to use. MangoApps has been named a "Market Leader" by Ovum Research and a "Cool Vendor" by Gartner...
The world's leading Cloud event, Cloud Expo has launched Microservices Journal on the SYS-CON.com portal, featuring over 19,000 original articles, news stories, features, and blog entries. DevOps Journal is focused on this critical enterprise IT topic in the world of cloud computing. Microservices Journal offers top articles, news stories, and blog posts from the world's well-known experts and guarantees better exposure for its authors than any other publication. Follow new article posts on Twitter at @MicroservicesE
Containers and microservices have become topics of intense interest throughout the cloud developer and enterprise IT communities. Accordingly, attendees at the upcoming 16th Cloud Expo at the Javits Center in New York June 9-11 will find fresh new content in a new track called PaaS | Containers & Microservices Containers are not being considered for the first time by the cloud community, but a current era of re-consideration has pushed them to the top of the cloud agenda. With the launch of Docker's initial release in March of 2013, interest was revved up several notches. Then late last...
There is no doubt that Big Data is here and getting bigger every day. Building a Big Data infrastructure today is no easy task. There are an enormous number of choices for database engines and technologies. To make things even more challenging, requirements are getting more sophisticated, and the standard paradigm of supporting historical analytics queries is often just one facet of what is needed. As Big Data growth continues, organizations are demanding real-time access to data, allowing immediate and actionable interpretation of events as they happen. Another aspect concerns how to deliver ...
WebRTC defines no default signaling protocol, causing fragmentation between WebRTC silos. SIP and XMPP provide possibilities, but come with considerable complexity and are not designed for use in a web environment. In his session at @ThingsExpo, Matthew Hodgson, technical co-founder of the Matrix.org, discussed how Matrix is a new non-profit Open Source Project that defines both a new HTTP-based standard for VoIP & IM signaling and provides reference implementations.
In his session at WebRTC Summit, Peter Dunkley, Technical Director at Acision, will look at creating interactive communications via the web by adding messaging, file transfer, and group communication (group chat and audio/video conferencing) into the web experience. He will also discuss potential applications of this technology in areas including B2B, B2C, P2P, and gaming. Peter Dunkley is Technical Director at Acision. He graduated from The University of Edinburgh in 2000 with a BSc (Hons) in Computer Science. After graduation Peter worked on a PSTN switch developing signalling stacks for SS...
The security devil is always in the details of the attack: the ones you've endured, the ones you prepare yourself to fend off, and the ones that, you fear, will catch you completely unaware and defenseless. The Internet of Things (IoT) is nothing if not an endless proliferation of details. It's the vision of a world in which continuous Internet connectivity and addressability is embedded into a growing range of human artifacts, into the natural world, and even into our smartphones, appliances, and physical persons. In the IoT vision, every new "thing" - sensor, actuator, data source, data con...
What if, during a snow emergency, an on-the-ground sensor could automatically trigger a relevant emergency notification related to snowfall and road impact. And then, after it’s triggered, that notification is delivered intelligently to individuals based on an extensive set of rules designed to alert the most available and capable responders. This “what if” question about “smart highways” is short-sighted. We are already there, and we are only getting started. While mainstream attention is paid to machine-to-machine communications, new technologies are being developed to make these communica...
The Internet of Things is not new. Historically, smart businesses have used its basic concept of leveraging data to drive better decision making and have capitalized on those insights to realize additional revenue opportunities. So, what has changed to make the Internet of Things one of the hottest topics in tech? In his session at @ThingsExpo, Chris Gray, Director, Embedded and Internet of Things, discussed the underlying factors that are driving the economics of intelligent systems. Discover how hardware commoditization, the ubiquitous nature of connectivity, and the emergence of Big Data a...
Scott Jenson leads a project called The Physical Web within the Chrome team at Google. Project members are working to take the scalability and openness of the web and use it to talk to the exponentially exploding range of smart devices. Nearly every company today working on the IoT comes up with the same basic solution: use my server and you'll be fine. But if we really believe there will be trillions of these devices, that just can't scale. We need a system that is open a scalable and by using the URL as a basic building block, we open this up and get the same resilience that the web enjoys.
SYS-CON Media announced today that @WebRTCSummit Blog, the largest WebRTC resource in the world, has been launched. @WebRTCSummit Blog offers top articles, news stories, and blog posts from the world's well-known experts and guarantees better exposure for its authors than any other publication. @WebRTCSummit Blog can be bookmarked ▸ Here @WebRTCSummit conference site can be bookmarked ▸ Here