Data Mining Practical Machine Learning Tools and Techniques

We will review some of the major results in random graphs and some of the more challenging open problems. We will cover algorithmic and structural questions. We will touch on newer models, including those related to the WWW.

Random graphs

Twitter, a microblogging service less than three years old, commands more than 41 million users as of July 2009 and is growing fast. Twitter users tweet about any topic within the 140-character limit and follow others to receive their tweets. The goal of this paper is to study the topological characteristics of Twitter and its power as a new medium of information sharing.We have crawled the entire Twitter site and obtained 41.7 million user profiles, 1.47 billion social relations, 4,262 trending topics, and 106 million tweets. In its follower-following topology analysis we have found a non-power-law follower distribution, a short effective diameter, and low reciprocity, which all mark a deviation from known characteristics of human social networks [28]. In order to identify influentials on Twitter, we have ranked users by the number of followers and by PageRank and found two rankings to be similar. Ranking by retweets differs from the previous two rankings, indicating a gap in influence inferred from the number of followers and that from the popularity of one's tweets. We have analyzed the tweets of top trending topics and reported on their temporal behavior and user participation. We have classified the trending topics based on the active period and the tweets and show that the majority (over 85%) of topics are headline news or persistent news in nature. A closer look at retweets reveals that any retweeted tweet is to reach an average of 1,000 users no matter what the number of followers is of the original tweet. Once retweeted, a tweet gets retweeted almost instantly on next hops, signifying fast diffusion of information after the 1st retweet.To the best of our knowledge this work is the first quantitative study on the entire Twittersphere and information diffusion on it.

https://ink.library.smu.edu.sg/cgi/viewcontent.cgi?article=7104&context=sis_research

What is Twitter, a social network or a news media?

The term “Linked Data” refers to a set of best practices for publishing and connecting structured data on the Web. These best practices have been adopted by an increasing number of data providers over the last three years, leading to the creation of a global data space containing billions of assertions— the Web of Data. In this article, the authors present the concept and technical principles of Linked Data, and situate these within the broader context of related technological developments. They describe progress to date in publishing Linked Data on the Web, review applications that have been developed to exploit the Web of Data, and map out a research agenda for the Linked Data community as it moves forward.

/pdf/linked-data-the-story-so-far-2a9zvmaysa.pdf

Linked Data - the story so far

Obesity now affects one in five children in the United States. Discrimination against overweight children begins early in childhood and becomes progressively institutionalized. Because obese children tend to be taller than their nonoverweight peers, they are apt to be viewed as more mature. The inappropriate expectations that result may have an adverse effect on their socialization. Many of the cardiovascular consequences that characterize adult-onset obesity are preceded by abnormalities that begin in childhood. Hyperlipidemia, hypertension, and abnormal glucose tolerance occur with increased frequency in obese children and adolescents. The relationship of cardiovascular risk factors to visceral fat independent of total body fat remains unclear. Sleep apnea, pseudotumor cerebri, and Blount's disease represent major sources of morbidity for which rapid and sustained weight reduction is essential. Although several periods of increased risk appear in childhood, it is not clear whether obesity with onset early in childhood carries a greater risk of adult morbidity and mortality. Obesity is now the most prevalent nutritional disease of children and adolescents in the United States. Although obesity-associated morbidities occur more frequently in adults, significant consequences of obesity as well as the antecedents of adult disease occur in obese children and adolescents. In this review, I consider the adverse effects of obesity in children and adolescents and attempt to outline areas for future research. I refer to obesity as a body mass index greater than the 95th percentile for children of the same age and gender.

Health Consequences of Obesity in Youth: Childhood Predictors of Adult Disease

Objective To outline the evolution of school food standards and their implementation and evaluation in each of the four countries of the UK since 2000. Design Review of relevant policies, surveys and evaluations, including country-specific surveys and regional evaluations. Setting UK: England, Wales, Scotland and Northern Ireland. Subjects Primary and secondary schools and schoolchildren. Results By September 2013 standards will have been introduced in all primary and secondary schools in the UK. Evaluations have varied in their scope and timing, relating to government forward planning, appropriate baselines and funding. Where standards have been implemented, the quality and nutritional value of food provided have improved. Emerging evidence shows improved overall diet and nutrient intake by school-aged children as a result. Conclusions The re-introduction of school food standards in the UK has not been centrally coordinated, but by September 2013 will be compulsory across all four countries in the UK, except in England where academies are now exempt. Provision of improved school food has had a demonstrable impact on diet and nutrition beyond the school dining room and the school gate, benefiting children from all socio-economic groups. Improved school food and dining environments are associated with higher levels of school lunch take up. Implementation of school food standards requires investment. It is critical to policy development that the value of this investment is measured and protected using planned, appropriate, robust and timely evaluations. Where appropriate, evaluations should be carried out across government departments and between countries.

/pdf/school-food-standards-in-the-uk-implementation-and-14jarwefmw.pdf

School food standards in the UK: implementation and evaluation.

The usefulness of the many on-line journals and scientific digital libraries that exist today is limited by the inability to federate these resources through a unified interface. The Open Archive Initiative (OAI) is one major effort to address technical interoperability among distributed archives. The objective of OAI is to develop a framework to facilitate the discovery of content in distributed archives. In this paper, we describe our experience and lessons learned in building Arc, the first federated searching service based on the OAI protocol. Arc harvests metadata from several OAI compliant archives, normalizes them, and stores them in a search service based on a relational database (MySQL or Oracle). At present we have over 320,000 metadata records from 18 data providers from various subject domains. We have also implemented an OAI layer over Arc, thus making hierarchical harvesting possible. The experiences described within should be applicable to others who seek to build an OAI service provider.

/pdf/arc-an-oai-service-provider-for-digital-library-federation-1jb8f4dlxc.pdf

Arc - An OAI Service Provider for Digital Library Federation

We have studied object persistence and availability of 1,000 digital library (DL) objects. Twenty World Wide Web accessible DLs were chosen and from each DL, 50 objects were chosen at random. A script checked the availability of each object three times a week for just over 1 year for a total of 161 data samples. During this time span, we found 31 objects (3% of the total) that appear to no longer be available: 24 from PubMed Central, 5 from IDEAS, 1 from CogPrints, and 1 from ETD. 1.0 Introduction We have measured the persistence and availability of digital objects in a variety of publicly available World Wide Web (WWW) digital libraries (DLs). We selected twenty DLs, and from those DLs selected 50 information objects, for a total of 1,000 information objects. Three times a week (Sunday, Tuesday and Friday early morning, Eastern Time zone) from November 21, 2000, through December 9, 2001, scripts were run that download the information object and record the number of bytes successfully transmitted. All tests were run from the machine ruby.ils.unc.edu (152.2.81.1; Solaris 2.7). When the terms \"unavailable\" and \"inaccessible\" are used below, it is important to remember that these terms are with respect to ruby.ils.unc.edu. We are particularly interested in the long-term availability of individual objects in the DL. Similar previous studies have looked at the availability of general http servers (Viles & French, 1995), or at the availability of general web pages (Douglis et al., 1997; Koehler, 1999; Koehler, 2000). One study looked at the availability of DL services that were layered on top of http (Powell & French, 2000). We find similar network and http server availability issues that these studies report. However, for evaluating the availability of individual objects, these studies are insufficient. Certainly, if the http server, DL service, or \"entry\" web page is missing, then the desired object will be unreachable. However, simply verifying the operation of an http server, DL service or web page does not imply that the actual object itself is still available or unchanged. On the assumption that being placed in a DL is indicative of someone's desire to increase the persistence and availability of an object, we expect DL objects to survive longer, change less, and be more available than general WWW content. Of the objects that appeared to be unavailable from the test data, we manually sought out the objects in the tested DL, and in the case of distributed DLs, we went to the original web sites. After doing Object Persistence and Availability in Digital Libraries http://www.dlib.org/dlib/january02/nelson/01nelson.html[5/3/2016 2:54:10 PM] so, we consider 31 of the 1,000 objects to be currently unavailable. It is possible that these objects are available in some other form, or by another name, and we were simply unable to find them. However, these 31 objects represent results returned in searching and browsing of the DLs in November 2000 that we cannot currently find. This percentage is similar to what Lawrence et al. (2001) report in their study of the persistence of URLs that appear in technical papers. For recently authored papers, they found over 20% of the URLs listed were invalid. However, manual searches were able to reduce the number of \"lost\" URLs to 3%. Since not all the URLs extracted for their study were necessarily objects in DLs, we are unsure if 3% lossage is generalizable. 2.0 Test Collection The twenty DLs we studied are listed in Table 1. We selected these DLs for their mixture of coverage, popularity, geographic locations, and data storage architectures. Some of the DLs have their own \"brand\" or \"identity\", some are part of an institution's library services, and others are simply report listings on a web page. However, we considered them to be DLs regardless of their own awareness or promotion of themselves as DLs. \"Contributor\" describes from where the DL's content comes, and \"Access\" indicates if the URLs for the objects represent direct access to the delivery format (i.e., PDF, PostScript) or if access goes through a \"wrapper\" service that delivers the content through a server-side process in addition to the http server. The appendix contains a tar file of all the objects, scripts used to test the objects, the test data, and the Matlab scripts used to generate the visualization of the data. DL Root Content Data Storage Contributor Access w.harvard.edu Astrophysics Centralized & distributed Publishers, Societies, Universities Wrapper ccdb.kek.jp Astrophysics Centralized Universities, Laboratories Wrapper citeseer.nj.nec.com Computer science Centralized & distributed Scraped From Web Pages Wrapper cogprints.soton.ac.uk Cognitive science Centralized Individual Authors Direct data.mpi-sb.mpg.de Mathematics, computer science Centralized MPI Wrapper ideas.uqam.ca Economics Distributed Individual authors Direct mtrs.msfc.nasa.gov Aerospace Centralized MSFC Direct pubmedcentral.nih.gov Medical science Centralized Publishers Wrapper stinet.dtic.mil General science Centralized Universities, Laboratories Wrapper www.arxiv.org Physics, mathematics, computer science Centralized Individual authors Wrapper www.inria.fr Computer science Centralized INRIA Direct www.jlab.org Physics Centralized JLab Direct www.ncstrl.org Computer science Distributed Universities Wrapper www.nzdl.org Computer science Centralized & distributed Universities Wrapper Object Persistence and Availability in Digital Libraries http://www.dlib.org/dlib/january02/nelson/01nelson.html[5/3/2016 2:54:10 PM] www.onera.fr Aerospace Centralized ONERA Direct www.rand.org Economics, mathematics, social sciences Centralized RAND Direct www.research.digital.com Computer science Centralized COMPAQ/DEC Direct www.santafe.edu Mathematics, economics Centralized SFI Direct www.slac.stanford.edu Physics Centralized Universities, Laboratories Direct www.theses.org General science Centralized Universities Direct

/pdf/object-persistence-and-availability-in-digital-libraries-k9ztixlovf.pdf

Object Persistence and Availability in Digital Libraries

/pdf/food-photographs-practical-guidelines-i-design-and-analysis-4lhn3qeu56.pdf

Food photographs: practical guidelines I. Design and analysis of studies to validate portion size estimates.

ObjectivesTo assess lunchtime provision of food and drink in English secondary schools and the choices and consumption of food and drink by pupils having school lunches, and to compare provision in 2011 with that in 2004.DesignCross-sectional data collected between October 2010 and April 2011. In each school, food and drink provision, including portion weights and number of portions of each item served at lunchtime, were recorded over five consecutive days. Caterers provided recipe information.SettingEngland.SubjectsA random selection of 5969 pupils having school lunches in a nationally representative sample of eighty secondary schools in England.ResultsCompared with 2004, significantly more schools in 2011 provided main dishes, vegetables and salads, water, fruit juice and other drinks on 4 or 5 d/week (P < 0·005). The number of schools offering items not permitted under the food-based standards for school food on 4 or 5 d/week fell significantly over time (P < 0·005), while the number not offering these items on any day increased significantly (P < 0·005). Meals eaten by pupils were well-balanced in relation to macronutrients.ConclusionsLunchtime food provision and consumption in secondary schools have improved considerably since 2004, following the introduction of new compulsory standards for school food in 2009. To maximise their energy and nutrient intake at lunchtime, pupils should be encouraged to select a full meal, and to take and eat more fruit and vegetables. Schools also need continued support to increase the micronutrient content of menus and recipes.

/pdf/the-impact-of-the-food-based-and-nutrient-based-standards-on-2fokgs5nj4.pdf

Michael L. Nelson

Papers

School food standards in the UK: implementation and evaluation.

Arc - An OAI Service Provider for Digital Library Federation

Object Persistence and Availability in Digital Libraries

Food photographs: practical guidelines I. Design and analysis of studies to validate portion size estimates.

The impact of the food-based and nutrient-based standards on lunchtime food and drink provision and consumption in secondary schools in England