Friday, October 2, 2015

Learn to speak or teach better in 30 minutes

This is a great article by Andrew Ng.

Saturday, April 25, 2015

Friday, March 13, 2015

Sunday, March 8, 2015

Thursday, February 26, 2015

Friday, January 9, 2015

My first teaching experience

I would have to say it was definitely a learning experience. I taught a database course to 40 mostly seniors and mostly male students. I spent the semester researching and learning which techniques were best used for teaching. I also learned how to create my own lectures, projects and exams. This experience definitely gave me a taste of what it would be like to teach professionally. I also learned a bit about myself. By the end of the semester I no longer felt uncomfortable with speaking in front of a group or answering questions and challenges on the fly. I also was impressed with many of the students in my class.

Now it is back to research!

And maybe teaching again in the future once I recover from this first one.

Friday, October 3, 2014

Taming Wild Big Data

Our latest paper for the AAAI Fall Symposium.
Abstract: Wild Big Data is data that is hard to extract, understand, and use due to its heterogeneous nature and volume. It typically comes without a schema, is obtained from multiple sources and provides a challenge for information extraction and integration. We describe a way to subduing Wild Big Data that uses techniques and resources that are popular for processing natural language text. The approach is applicable to data that is presented as a graph of objects and relations between them and to tabular data that can be transformed into such a graph. We start by applying topic models to contextualize the data and then use the results to identify the potential types of the graph’s nodes by mapping them to known types found in large open ontologies such as Freebase, and DBpedia. The results allow us to assemble coarse clusters of objects that can then be used to interpret the link and perform entity disambiguation and record linking.

Tuesday, September 30, 2014

Thursday, September 11, 2014

Learning Julia

julia is a dynamic programming language getting a bit of attention. I am running a few tutorials and learning the language. Some resources are listed below in case you are interested....

Learn about julia
Quick tutorial
Another tutorial
Google group

Thursday, December 19, 2013

Lego Car

This is just too cool, a lego car tha runs on compressed air.

Tuesday, November 26, 2013

Kano kit

Something to think about...

Source: https://twitter.com/AIIsAwesome/status/404341645509812224/photo/1

Monday, November 18, 2013

Just received notice Qualcomm Toq Smartwatch is available Dec 2nd

Qualcomm Toq Smartwatch is available as of Dec 2nd for a starting cost of $349.99 (OUCHY!).

Sunday, November 17, 2013

AAAI Symposium

I've been spending the weekend at the AAAI Symposium. There have been quite a few interesting talks.
John Laird gave an interesting talk on General Intelligence.
Andrew Ng also gave an interesting talk, on Deep Learning.

Thursday, October 31, 2013

3D on the Web - Introduction to WebGL

This is an interesting talk offered through ACM.
Supplementary Learning Resources from Alain Chesnais
Collada:
Official website http://collada.org/
Tutorials https://collada.org/mediawiki/index.php/Portal:Tutorials
WebGL:
Official website http://www.khronos.org/webgl/
Tony Parisi's Tutorials http://learningwebgl.com/
Three.js:
Official website http://threejs.org/
Ilmari Heikkinen's Tutorial http://fhtr.org/BasicsOfThreeJS/#2
X3Dom:
Official website http://www.x3dom.org/
Introductory tutorial http://x3dom.org/docs/dev/tutorial/firststeps.html

Friday, October 25, 2013

Saturday, October 5, 2013

4D Printers

This is pretty cool, researchers are trying to add a 4th dimension to 3D printing. What they are trying to do is print material that can change over time, not just shape, but based on some external stimuli, change of behavior. I find this incredibly interesting.

The article is titled, "’4D printing’ adaptive materials" and is found on kurzweilai.net
Read the article at http://www.kurzweilai.net/4d-printing-adaptive-materials.

A great Ted talk on this same topic:

Thursday, October 3, 2013

Google Glass

Our lab, ebiquity, has been playing with Google Glass. So now I am hooked and wondering what sort of app I could develop for Google Glass. I've been doing a little reading on Google glass and came across this blog. The developer, Lance Nanek developed an interesting implementation of panning using head movement.

Watch the video to learn more:


Very cool stuff.

More information for developers is here.

And yet more info for developers.

And if you want Google Glass, then keep up with the latest news.

Wednesday, October 2, 2013

Mid-Atlantic Student Colloquium on Speech, Language and Learning

UMBC is hosting the Mid-Atlantic Student Colloquium on Speech, Language and Learning.

Register online.

The schedule is now posted.

Snapshot of the schedule:

09:00-09:45 Registration, set up

09:45-10:00 Opening

10:00-11:20 Oral presentations I

Lushan Han, Abhay Kashyap, Tim Finin, James Mayfield and Jonathan Weese (UMBC & JHU). Semantic Textual Similarity Systems

Keith Levin, Aren Jansen and Ben Van Durme (JHU). Toward Faster Audio Search Using Context-Dependent Hashing

Shawn Squire, Monica Babes-Vroman, Marie Desjardins, Ruoyuan Gao, Michael Littman, James MacGlashan and Smaranda Muresan (UMBC & Brown). Learning to Interpret Natural Language Instructions

Viet-An Nguyen, Jordan Boyd-Graber and Philip Resnik (UMCP). Lexical and Hierarchical Topic Regression

11:20-12:10 Poster session I

Posters

12:10-12:40 Lunch

12:40-1:40 Panel

"How to be a successful PhD student and and transition to a great job"
Marie desJardins (UMBC)
Mark Dredze (JHU)
Claudia Pearce (DoD)
Ian Soboroff (NIST)
Hanna Wallach (UMass)


1:50-3:10 Oral presentations II

Qingqing Cai and Alexander Yates (Temple). Large-scale Semantic Parsing via Schema Matching and Lexicon Extension

William Yang Wang and William W. Cohen (CMU). Efficient First-Order Probabilistic Logic Programming for Natural Language Inference

Xuchen Yao, Benjamin Van Durme, Chris Callison-Burch, Peter Clark (JHU & UPenn & AI2). Semi-Markov Phrase-based Monolingual Alignment

Wei Xu, Alan Ritter and Ralph Grishman (NYU). Gathering and Generating Paraphrases from Twitter with Application to Normalization

3:10-4:00 Poster session II

Posters

4:00-5:00 Breakout sessions

NLP in low resource settings, Ann Irvine (JHU)

Dynamic Programming: Theory and Practice, Alexander Rush (Columbia/MIT)

NELL: Never Ending Language Learning, Partha Pratim Talukdar (CMU)

5:00 Closing

5:15 - 7:00 Wine down

Wine and beer at Flat Tuesdays, UMBC Commons

Sunday, September 29, 2013

Originality

“It is better to fail in originality than to succeed in imitation.”
--Herman Melville

Friday, September 27, 2013

Integrity

“Truth at last cannot be hidden. Dissimulation is of no avail. Dissimulation is to no purpose before so great a judge. Falsehood puts on a mask. Nothing is hidden under the sun.” ― Leonardo da Vinci

“Stars hide your fires; let not light see my black and deep desires: The eyes wink at the hand; yet let that be which the eye fears, when it is done, to see” ― William Shakespeare, Macbeth

Wednesday, September 25, 2013

ubuntu 12.04 lts - No video mode activated

After 5 hours of debugging, I finally was able to work around the issue.
In /etc/default/grub
Commented out:
GRUB_DEFAULT
GRUB_HIDDEN_TIMEOUT
GRUB_HIDDEN_TIMEOUT_QUIET
GRUB_TIMEOUT
Changed
GRUB_CMDLINE_LINUX_DEFAULT="nomodeset"
Get rid of the reference to "splash" because that is what is crashing.
Ref 1
Ref 2
Ref 3
Ref 4
Ref 5
I also did the following:
cd /usr/share/grub/
sudo cp *.pf2 /boot/grub
Finally I could boot but the mouse pointer was MIA.
Did this to get it back:
sudo modprobe -r psmouse
sudo modprobe psmouse proto=imps




NOW I CAN FINALLY CATCH UP ON MY WORK!

Tuesday, September 24, 2013

References for graphs in R

This link provides pretty simple examples but useful. Adding error bars is not completely straightforward, this link gives a good explanation.

Wednesday, September 18, 2013

Data Fusion

My poster on data fusion.

How to write a good research paper and give a good research talk

Good reference for research paper and presentation advice.

Tuesday, September 17, 2013

Interesting Blog for Graduate Students

I found a few posts that were useful here.

Sunday, September 15, 2013

IEEE International Conference on Semantic Computing 2013

The IEEE ICSC.

NLP Resources

I am spending time this semester learning NLP since my work overlaps with NLP. I found a free ebook for learning NLP in Python. Another link for this book is here.
At the UMBC NLP course web site there are also slides available.
In particular, I have been working with OpenNLP which so far has been very useful. However, I am at the point of doing in-doc coref and having a lot of problems. There is not really any documentation on the in-doc coref api calls but I did find someone who dug into the code a bit and found a way to do it. However, so far, when executing my implementation, it runs forever. I hope to have an update soon.

Never Ending Learning (NELL)

Attended a very interesting talk related to Nell. The work is from Carnegie Mellon. If you are interested in machine learning, particularly how to perform learning over time, you may find this work of interest.

UMBC ebiquity group

Our group is performing interesting research by blending semantic computing with security, mobile devices, medical informatics and big data problems. Some of this research overlaps quite a bit with natural language processing. Read our publications to see the latest research coming from our lab.

Monday, September 9, 2013

Powerpoint Alternatives

I have been looking for an alternative to powerpoint that works reasonably well. So far OpenOffice and LibreOffice are not sufficient, especially when working on a team of Windows users. The following article provides a good list. I don't have a suggestion yet but would love to hear what others are using....

MASC 2013 Call For Papers Still Open

The 2013 Mid-Atlantic Student Colloquium on Speech, Language and Learning is still open.

Tuesday, July 23, 2013

System76 Ubuntu laptops

I spent over 6 months researching laptops and finally decided to go with a System76 Ubuntu laptop. It has been just less than 1 month but I am loving my new lemur. Review to come... System76 Lemur Ultra

Saturday, May 11, 2013

Bias and Variance Tradeoff

There is a great blog entry that describes this from a practical standpoint. If references the following lecture also.

Tuesday, April 9, 2013

How to store billions of triples...for free

So far I like, http://sourceforge.net/apps/mediawiki/bigdata/index.php?title=GettingStarted need this too: http://www.openrdf.org/doc/sesame2/users/ch07.html

LDA - Step by Step in R

Was able to get an example running very quickly with this tutorial. http://www.rtexttools.com/1/post/2011/08/getting-started-with-latent-dirichlet-allocation-using-rtexttools-topicmodels.html

Topic Modeling - Great Resource

Excellent resource! http://www.cs.princeton.edu/~blei/topicmodeling.html

SVMs - Good Description

http://nlp.stanford.edu/IR-book/html/htmledition/support-vector-machines-the-linearly-separable-case-1.html

Building Templates for Basic Entity Types

http://schema.org/Person http://schema.org/Organization http://nlp.cs.nyu.edu/ene/version7_1_0Beng.html

Learning Programming by means of Python

This is a very basic beginners tutorial. Good for those just learning programming. http://cscircles.cemc.uwaterloo.ca/

Monday, September 3, 2012

PCA, SVD, LSA

Great links to learn and understand these concepts:
PCA Tutorial
SVD and PCA discussion
LSA Tutorial

Saturday, February 25, 2012

Mining Twitter Article (Not technical)

This is an interesting article http://isc.sans.edu/diary.html?storyid=5728 due to the fact that they have links that are interesting related to mining Twitter. It is a little outdated and a few of the links do not work but still semi-useful. Keep in mind data sets that were previously available, for example http://snap.stanford.edu/data/twitter7.html, are no longer available due to a Twitter request (read about it here). However you can still use the Twitter API to get data, you are just limited to the number of tweets you can get per day/session (can't remember). Also useful is this article.

Paper Summary - Short text classification in twitter to improve information filtering

Short text classification in twitter to improve information filtering, B. Sriram and D. Fuhry and E. Demir and H. Ferhatosmanoglu,2010
This paper describes research that classifies tweets using a reduced set of features. In this approach they try to classify text into the following set of classes "News, Events, Opinions, Deals, and Private Messages". The problem they present is the curse of dimensionality problem that results from trying to conquer the spareness issue related to classifying twitter messages. Other research typically uses external knowledge bases to support tweet classification. They argue this can be slow due to the need to excessively query the external knowledge base. Important points about this paper:
1. They provide a very useful discussion of Twitter and tweets
2. How they classify tweets is interesting worth another review

Latex Tip - Controlling placement of figures and tables

This was a useful article for controlling placement of figures and tables. http://robjhyndman.com/researchtips/latex-floats/

Paper Summary - Linking Social Networks on the Web with FOAF: A Semantic Web Case Study

Linking Social Networks on the Web with FOAF: A Semantic Web Case Study,J. Golbeck and M. Rothstein, 2008
Another paper related to FOAF and the Semantic Web. This paper examines linking FOAF identities across social networks. They propose that it would be better to merge these accounts across sites so a user has one social network. This may have been an interesting idea in 2008 but I'm not sure if this is relevant now seeing as some social networks let you bring in contacts from other sites. In general, this paper can be excluded from further analysis.

Resource - Writing and Presenting Your Thesis or Dissertation

Writing and Presenting Your Thesis or Dissertation, S. Joseph Levine, Ph.D. http://www.learnerassociates.net/dissthes/ Another useful resource for writing the dissertation. They have a section on writing the proposal which I found useful.

Paper Summary - Twitter Sentiment Classification using Distant Supervision

Twitter Sentiment Classification using Distant Supervision, A. Go and R. Bhayani and L. Huang, 2009, Technical report, Stanford Digital Library Technologies Project
This paper relates to classifying sentiment found on Twitter. They use machine learning and are able to construct training data by using the Twitter API and emoticons present among tweets. The standard :) and :( are used to determine if a tweet contains positive or negative sentiment. The key points are 1.) they picked an efficient way to construct their training sets, 2.) Tweets are harder to classify because their length can not exceed 140 characters, and 3.) their results were promising for classifying the sentiment of the tweets.

Friday, February 17, 2012

Data Mining Resources

This thread has a lot of useful links for resources to help one studying data mining. It is mainly to help one build the mathematical background.

Friday, February 10, 2012

Data Mining and Machine Learning

I wished to understand the distinction between data mining and machine learning. This presentation (Machine Learning and Data Mining: 01 Data Mining) is useful.

Tuesday, February 7, 2012

Khan Academy

If you need to review concepts from Calculus, Linear Algebra, or Probability.
This is a good resource:
Khan Academy
I used this to review Linear Algebra concepts for my Data Mining course. They have quite a few topics.

Cheers.

Wednesday, January 4, 2012

Advice Collection

I came across a useful collection of links for Ph.D. students. It offers dissertation advice, presentation advice, and more....I read some of these articles in the past but it is nice to have a central location for reference.

Saturday, December 24, 2011

Neural Network Framework for Java

I spent the last month learning how to use Self-Organizing Maps (SOM) for my Neural Network course. I used a SOM to perform instance matching (which is not typically what it is used for) with the intention that possibly it could be used in a 2-level fashion or with some other supervised approach. Think of SOM as a clustering technique. It maps high dimensional data into a lower dimension (typically 2-D) space and it enables one to visually see the data in 2-D. The beauty of a SOM is that it is unsupervised which means you do not need to specify the desired output for your training set.

It outperformed K-Means when running comparison tests using the OAEI IIMB benchmark both in F-Measure scores and CPU time.


I used Encog for the Neural Net framework. I experienced a lot of memory issues but for the most part I was quickly running a SOM, K-Means and SVM comparison test.

For the next test, I think using Matlab, Weka or R might be a better approach. As much as I like to keep things nice and clean in the code. I quickly have memory issues as I increase the number of instances to test.

Code Sample for Encog SOM (based on the Encog example):

//Set of the training data, no desired output in this case
MLDataSet training = new BasicMLDataSet(trainingInput,null);

// Create the SOM neural network with an input count and an output count
// This is basically your input node size and output node size
// One point of improvement
SOM network = new SOM(inputNodeSIze,ouputNodeSize);

//reset the nework
network.reset();

//Here you specify your parameters i.e. learning rate and neighborhood function
//I used the NeighborhoodSingle here but clearly that is not the best choice
//Next round of tests will use a RBF and a GaussianFunction
//.7 for learning rate is not unreasonable
BasicTrainSOM train = new BasicTrainSOM(
network,
0.7,
training,
new NeighborhoodSingle());
//new NeighborhoodRBF(sizes, RBFEnum.Gaussian)

//store the winner in a space in the 2-d array reserved
//calling code will lump instances that have the same winner
//to determine which instances are 'similar'
double[][] newItems = new double[input.length][];
int i=0;
for (double[] item: input)
{
item[item.length-2]=network.winner(new BasicMLData(item));
newItems[i] =item;
i++;
}
Encog.getInstance().shutdown();

Saturday, August 20, 2011

Paper Summary - Toward Conditional Models of Identity Uncertainty with Application to Proper Noun Coreference - Part 1

Toward Conditional Models of Identity Uncertainty
with Application to Proper Noun Coreference
A. McCallum and B. Wellner


This paper is interesting. They make the point that pairwise decisions may not always be independent of others. One may be able to resolve inconsistencies by using a dependence model. They mention work, Relational Probabilistic Model, which captures this dependence. However since it is a generative model, they state this could lead to complexities due to many features with varying degrees of granularity. They discuss Hidden Markov models and conditional random fields briefly and Relational Markov networks as a similar model but improved classification.

They then discuss their work specifically which is "three conditional undirected graphical
models for identity uncertainty" which make the coreference decisions. Their first model connects mentions, entity-assignments, and each attribute of the mention. Edges indicate dependence. There is the concept of a clique, parameters may be part of different cliques which results in patterns of parameters called clique templates. Parts of the graph that depend on a number of entities are removed and replaced with random variables indicating coreference (Read this paper again to make sure we are clear on this). Per-entity attribute nodes are removed and replaced with attributes of mention. They then use graph partitioning. There is a lot in this paper and really requires another read to understand their methods better.

Paper Summary - Disambiguation and Filter Methods in Using Web Knowledge for Coreference Resolution

Disambiguation and Filter Methods in Using Web Knowledge for Coreference Resolution
O. Uryupina and M. Poesio

They describe how they use Wikipedia and Yago to increase their Coreference Resolution performance. They use BART to support their efforts. Their classification consists of a anaphor and a potential antecedent, as they describe. Using their associated feature vectors, they use a 'maximum entropy classifier' to determine coreference. They used Wikipedia to improve their aliasing algorithm, which would perform string matching functions. They use Wikipedia based information as a feature, and to disambiguate mentions. They use Yago to supplement their efforts when there are too few features to make any reasonable decisions related to coreference. Yago information is also incorporated as a feature. They tested using ACE with reasonable scores.

Using these publicly available knowledge bases appears to improve performance (2-3% in this case). Something to think about....

Monday, August 8, 2011

Stanford Online AI Course

This course is offered for Fall 2011 semester and the instructors are Sebastian Thrun and Peter Norvig. It should be a good class. The formal title is "Introduction to Artificial Intelligence".

Join

Wednesday, July 20, 2011

Boom Time In Silicon Valley?

In case you missed this over the weekend, apparently in Silicon Valley the next big boom is occurring, at least according to the LA Times.

For those keeping their eye on the market for that special time to start-up, this may be good news. Still too early to know for sure.

Friday, July 15, 2011

Intuition

There was an interesting question posed on the Linked In AGI group discussion board:
Has anyone put out a suggestion on how to impliment an "Intuition" engine?

Responses were also quite interesting...

Has anyone successfully built an intuition engine? The responses ranged from a weak description of how one might do this to long detailed descriptions of current research that has been ongoing for many years.

If this sounds interesting you may want to join the Linked In group AGI — Artificial General Intelligence.

Or go to the AGI Conference in August .

Linked Data Paper Summary

"Linked Data - The Story So Far", C. Bizer, T. Heath, T. Berners-Lee, 2009, http://eprints.ecs.soton.ac.uk/21285/1/bizer-heath-berners-lee-ijswis-linked-data.pdf


My work will support working with linked data so I am attempting to build a better understanding of this topic.

This paper is good for providing a very basic understanding of linked data. If you are new to the concept of linked data, this is a good starting paper to read. It provides basic principles, examples, and isn't too technical.

If you already have a good understanding of the basics, skip this paper. I read it in about 10 minutes and it was pretty much just a review of what I already knew.

Hadoop Meet-up - Large Scale Graph Processing On HBase and Map/Reduce on Greenplum

I attended the Hadoop Meet-up on Tuesday titled "Large Scale Graph Processing On HBase and Map/Reduce on Greenplum". You can view the event here.

I attended this event for two reasons: It has been a couple of years since I worked intimately with Hadoop and I wanted to see how others are using it. I was also hoping the discussion on Large Scale Graph Processing would be useful for my research.

Though the presentations were somewhat stimulating, I didn't find much I could use for my work.

Tuesday, June 21, 2011

Canopy Clustering

"Efficient Clustering of High Dimensional Data Sets with Application to Reference Matching", McCallum,Nigam,Ungar,http://www.kamalnigam.com/papers/canopy-kdd00.pdf

This paper discusses a different type of clustering, titled canopy clustering. It is an interesting idea. There are basically two thresholds, using a 'cheap distance metric', we evaluate a list of points. Threshold 1 is > than Threshold 2. Pick one point to compare with all the other points in the list. When the distance between the two points falls within T1 put the points into a canopy. If the distance falls within T2 then remove point from list. We generate the canopies this way and work through the list until empty.

We can then apply our second level of clustering to each canopy and are pretty much guaranteed that if two points do not fall into the same canopy then they are likely not to be co-referent and therefore do not need to be evaluated.

This is efficient and elegant. Currently the only implementation that I found of canopy clustering is in Mahout. I am building my own implementation though to get a feel for how well it works.

SimHash: Hash-based Similarity Detection

"SimHash: Hash-based Similarity Detection", Sadowski, Levin, 2007.

This paper outlines a hash algorithm that can be used for similarity detection. Most hash algorithm are designed to offer low collision and hash values for similar strings can vary quite a bit. This hash basically sets out to achieve the opposite, higher collision and hash keys for similar strings are similar if not the same.

If you cannot use term frequency and need a numeric representation of a string for statistical processing, what process can be used? Using an integer-based hash is one way to achieve this, though in my opinion it is not the most sophisticated of approaches.

An implementation of this algorithm showed that it is a reasonable approach for hashing strings with the intent to determine similarity. I found minor issues which I will address by altering the algorithm.

Results showed that this is a reasonable approach....

Monday, May 16, 2011

Narrowing the Modeling Gap: A Cluster-Ranking Approach to Coreference Resolution

"Narrowing the Modeling Gap: A Cluster-Ranking Approach to Coreference Resolution"
Journal of Artificial Intelligence Research 40 (2011) 469–521 Submitted 06/10; published 02/11
Altaf Rahman altaf@hlt.utdallas.edu
Vincent Ng vince@hlt.utdallas.edu
Human Language Technology Research Institute
University of Texas at Dallas
800 West Campbell Road; Mail Station EC31
Richardson, TX 75080-3021 U.S.A.
http://www.jair.org/media/3120/live-3120-5478-jair.pdf

-Long paper, very thorough
-A lot of history, use the citations in this paper
-Learn more about "centering algorithms"
-Describes three different models, mention-pair,entity-mention and mention-ranking
-Outlines key features and deficiencies of each
-In particular the transitivity property is not addressed in the mention-pair model so clustering is used
-Mention-ranking outperforms mention-pair
-Describe a cluster-ranking approach combines both models
-Use lexicalization and knowledge of anaphoricity
-Used ACE for experiments

Interesting:



  1. "Specifically, a classifier that is trained on
    coreference-annotated data is used to determine whether a pair of mentions is co-referring
    or not. However, the pairwise classifications produced by this classifier (which is now commonly
    known as the mention-pair model) may not satisfy the transitivity property inherent
    in the coreference relation, since it is possible for the model to classify (A,B) as coreferent,
    (B,C) as coreferent, and (A,C) as not coreferent. As a result, a separate clustering mechanism
    is needed to coordinate the possibly contradictory pairwise classification decisions and
    construct a partition of the given mentions."

  2. Read about Lappin and Leass’s algorithm

  3. Read about centering algorithms

  4. "the distinction between
    classification and ranking applies to discriminative models but not generative models.
    Generative models try to capture the true conditional probability of some event. In the context
    of coreference resolution, this will be the probability of a mention having a particular
    antecedent or of it referring to a particular entity (i.e., preceding cluster). Since these probabilities
    have to normalize, this is similar to a ranking objective: the system is trying to raise
    the probability that a mention refers to the correct antecedent or entity at the expense of
    the probabilities that it refers to any other. Thus, the antecedent version of the generative
    coreference model as proposed by Ge et al. (1998) resembles the mention-ranking model,
    while the entity version as proposed by Haghighi and Klein (2010) is similar in spirit to the
    cluster-ranking model."

Friday, July 2, 2010

Linux on Windows

If you aren't aware of wubi yet. It is actually a great way to run Linux on Windows Ubuntu flavor. The installation is easy and you can control how much disk space you want to use. I am slowly rebuilding my laptops to run Linux but in the meantime this is a nice way to keep Windows and run Linux too.

Get it

Saturday, May 29, 2010

Hadoop + SPARQL

I began working with cloud computing about 2 years ago because of my interest in using this environment for semantic web applications. It seems to be of interest to others too.

https://opencirrus.org/content/sparql-query-over-hadoop-very-large-rdf-dataset
http://portal.acm.org/citation.cfm?id=1779599.1779605
http://cs264.org/projects/web/Rohloff_Kurt/rohloff/index.html

Sunday, April 25, 2010

Paper Summary - A Framework for Combining Ontology and Schema Matchers with Dempster-Shafer

"Paper Summary - A Framework for Combining Ontology and Schema Matchers with Dempster-Shafer", P. Besana


This is a short paper about using Dempster-Shafer for ontology mapping. They have a tool based on their work: PyontoMap. This paper is really relevant so the summary will be deferred.

Paper Summary - BeliefOWL: An Evidential Representation in OWL Ontology

Amira Essaid and Boutheina Ben Yaghlane, BeliefOWL: An Evidential Representation in OWL Ontology, pages 77-80, International Semantic Web Conference, International Workshop on Uncertainty Reasoning for the Semantic Web, Washington DC, USA, 2009.


This paper is very short, only 4 pages. It starts with a discussion of how uncertainty is represented currently in ontologies using either probabilistic or fuzzy approaches. It then proposed the Dempster-Shafer approach as another option. They discuss the work by :
Ben Yaghlane,B.: Uncertainty representation and reasoning in directed evidential
networks, PhD thesis, Institut Sup´erieur de Gestion de Tunis Tunisia, 2002.

which is work related to representing uncertainty using a DAG. I haven't read this paper yet but it certainly seems like a good read.

This paper then goes on with a presentation of BeliefOWL, their uncertainty extension to OWL.


They define two classes to represent prior evidence:


- enumerates different masses and has object property which specifies the relation between itself and .


- expreses prior evidence and has property



They define two classes which represent conditional evidence:


- has an object property of


- conditional evidence with property



They construct an evidential network by translating the OWL ontology into a DAG. They then assign masses to nodes in the DAG. Details of this work are mentioned but briefly.

Overall I don't know if this helps my work in anyway except to see some uses of DS with ontologies.

Paper Summary - Uncertainty in Ontologies: Dempster-Shafer Theory for Data Fusion Applications

"Uncertainty in Ontologies: Dempster-Shafer Theory for Data Fusion Applications", A.
Bellenger1 and S. Gatepaille, Defence and Security Information Processing, Control and Cognition department, France

This paper is relevant to my work because they use DS to represent uncertainty in ontologies. They do this by creating an upper ontology that contains the DS measures calculated i.e mass, belief, plausibility, etc.


The paper starts with a background in data fusion and gives some examples of how uncertainty is captured in ontologies and why it is important to represent uncertainty. They define uncertainty as "incomplete knowledge, including incompleteness, vagueness, ambiguity, and others". In addition to the natural occurrence of uncertainty in data, it is also a product of fusing data which may be acquired from different sources.

This is an interesting statement: " If the user/application is not able to decide in favor of a single alternative (due to insufficient trust in the respective information sources), the aggregated statement resulting from the fusion of multiple
statements is typically uncertain. The result needs to reflect and weight the different information inputs appropriately, which typically leads to uncertainty."

This is the common in military applications and in general knowledge bases because one attempts to acquire supporting data for entities in the knowledge base from various sources that can be unreliable.

They briefly discuss the shortcomings in current traditional methods to handle uncertainty in ontologies. They state that since ontologies are designed to contain concepts and relations only that describe asserted facts about the world, that they are not designed to handle uncertainty. The facts asserted are assumed to be 'true'. Therefore even information that is not certain to be 'true' are stored and lead to errors or inaccurate information. There is not a standard way to handle uncertainty currently (can read more on this).

They discuss how probability is used as a way to represent uncertainty in ontologies. They discuss some existing work in this area including (BayesOWL). The problem with this approach in particular is that it does not account for OWL properties, instances of the ontologies or the data types. There are also extensions to DL (Pronto is one of them), however performance is a problem. There are also Fuzzy approaches that exist.

They then discuss using DS. DS is presented as a generalized probability theory, however books related to this topic are not exactly is agreement with this representation. Masses are calculated and the sum of these masses make up the beliefs. It is also noted that is supports combining evidence from different sources which makes it especially useful for fusing data from different sources. They note work that actually use DS to handle the inconsistencies produced by mapping ontologies. However it also highlights a relevant paper that translates an OWL taxonomy into a directed evidential network.

The rest of the paper discusses their approach and how they use DS for modeling and reasoning. The point they make about uncertainty and why probabilistic methods can't represent it accurately is p-methods do not represent the absence of information very well. One needs to specify prior and conditional probabilities. They argue this leads to a minimax error due to is nature of symmetry prior probability assignment (.5) when information is not available. With DS missing information is not applied unless obtained indirectly. It allows one to specify a degree of ignorance (some define this as an upper and lower bound). They find this property to be appealing.


Probabilistic approaches use singletons only where DS allows one to use composites in addition to singletons. This is powerful. With probability theory there is a relationship between an event and its negation, DS does not imply a relationship between an event and its negation, it only models beliefs associated with a class.

They mention an additional point that I find makes this approach appealing. DS provides a way to combine evidence from different sources. This makes it especially useful for fusion.

They state, "the evidence theory is much more flexible than the probability theory". This is a strong statement and I'm not sure if it is completely true based on other papers that show how both Bayesian and DS can produce similar results.

Ok the paper ends with their approach. They discuss their proposed model which is an upper ontology representing the uncertainty. A DS_Concept which is a subclass of OWL:Thing has a DS_Mass, DS_Belief, DS_Plausibility, and a DS_Source. The Uncertain_Concept represents a concept that is part of the set. There is an object property is_either which has a range of owl:Thing so that all instances can be used.

This paper isn't cited by anyone else but I think there are good ideas proposed here and I am using this paper in my 601 work.

Saturday, April 24, 2010

Papers To Read

http://www.dsto.defence.gov.au/publications/2563/DSTO-TR-1436.pdf
http://www.isif.org/fusion/proceedings/fusion03CD/special/s31.pdf
http://uima.apache.org/downloads/releaseDocs/2.3.0-incubating/docs/pdf/tutorials_and_users_guides.pdf
http://www.autonlab.org/tutorials/bayesnet09.pdf
http://spiedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PSISDG004051000001000255000001&idtype=cvips&gifs=yes&ref=no
http://www2.research.att.com/~lunadong/publication/fusion_vldbTutorial.pdf
http://www.aaai.org/aitopics/pmwiki/pmwiki.php/AITopics/Uncertainty
http://www.cs.cmu.edu/afs/cs/academic/class/15381-s07/www/slides/032207probAndUncertainty.pdf
cox's theorem
http://www.britannica.com/bps/additionalcontent/18/35136768/Data-Fusion-for-Traffic-Incident-Detection-Using-DS-Evidence-Theory-with-Probabilistic-SVMs
http://data.semanticweb.org/workshop/ursw/2009/paper/main/5/html
http://portal.acm.org/citation.cfm?id=1698790.1698821
http://volgenau.gmu.edu/~klaskey/papers/LaskeyCostaJanssen_POFusion.pdf
http://www.slideshare.net/rommelnc/ursw-2009-probabilistic-ontology-and-knowledge-fusion-for-procurement-fraud-detection-in-brazil
http://www.eurecom.fr/~troncy/Publications/Troncy_Straccia-eswc06.pdf
http://www.glennshafer.com/assets/downloads/articles/article48.pdf
http://www.fusion2008.org/tutorials/tutorial05.pdf
http://www.google.com/url?sa=t&source=web&ct=res&cd=5&ved=0CCcQFjAE&url=http%3A%2F%2Fciteseerx.ist.psu.edu%2Fviewdoc%2Fdownload%3Fdoi%3D10.1.1.62.9835%26rep%3Drep1%26type%3Dpdf&rct=j&q=dempster+shafer+tutorial&ei=UprNS4m9K4P88Ab5v-GVAQ&usg=AFQjCNFUUt_xSeT2QOkrqYvsLySWOllqCw&sig2=RLqpJoODSs1kgLFK869Ikw
http://www.cs.cf.ac.uk/Dave/AI2/node87.html
http://www.autonlab.org/tutorials/bayesnet09.pdf
http://sinbad2.ujaen.es/sinbad2/files/publicaciones/186.pdf
http://www.ensieta.fr/belief2010/papers/p133.pdf
http://www.gimac.uma.es/ipmu08/proceedings/papers/057-MerigoCasanovas.pdf
http://www.sas.upenn.edu/~baron/journal/jdm7803.pdf
http://classifier4j.sourceforge.net/usage.html
http://sunsite.informatik.rwth-aachen.de/Publications/CEUR-WS/Vol-527/paper1.pdf

Research Paper Summary - A General Data Fusion Architecture

H Carvalho, W Heinzelman, A Murphy, and C Coelho. A
general data fusion architecture. In Int. Conf. on Info. Fusion,
pages 1465–1472, 2003.


This is a short paper that describes an architecture for data fusion. What they are proposing is a taxonomy that defines 3 types of fusion: data oriented, variable oriented, and a mixture of the two. They are making a clear distinction between data as a measurement of the environment and variable as determined by feature extraction.

They describe examples of sensor data and state that the data needs to be pre-processed before fused. The pre-processing can involve conversions of a signal or filtering or handling noise. After pre-processing the data can be fused and they are proposing a 3-level data fusion framework. They begin by classifying the data as defined by the taxonomy. Basically when the fusion occurs defines what type of fusion we are dealing with (data, variable or mixture).

They go into a few examples of using this architecture. In general, the paper is not detailed enough to understand if the approach is viable. It is high level and short. It does provide additional information about the formalities of data fusion which is useful.

Paper Summary - A New Technique for Combining Multiple Classifiers using The Dempster-Shafer Theory of Evidence

Al-Ani, A. & Deriche, M. (2002) A new technique for combining multiple classifiers using the dempster shafer theory of evidence. In Journal of Artificial Intelligence Research, 17, (pp. 333—361)

This paper describes a new technique based on Dempster-Shafer to combine classifiers. The basic premise is that different types of features may be used depending upon the application. With different features, the same classifier may not always be best. So based on the features, a different classifier may outperform others. By combining classifiers they propose this is an efficient way to achieve the best classification results.

There are two problems defined by others, how to determine which classifiers to use and how to combine the classifier results to get the best results. They are addressing the second question in this paper.


They categorize the output of classification algorithms into 3 levels:

  • the abstract - outputs a unique label

  • the rank - ranks all labels with label at top as first choice

  • the measurement levels - attributes to each class a value reflecting degree of confidence that input belongs to class



They state the measurement level contains the 'highest amount of information' and they use this level for their work.

Two combination scenarios mentioned:

  • all use the same representation of input pattern

  • each uses its own representation



Relating to item 2 they found from another study that using a joint probability distribution using the sum rule gave the best results. They also quote a study that used weighted sums, and another that used a cost function to minimize MSE in conjunction with A NN. In this same study that used NN, a number of NNs were used to produce linear combination. Combining the results from the NN, they used Dempster-Shafer theory. They give a few other approaches and then the rest of the paper discusses their approach.

They combine classifier results using a number of different feature sets. Each feature set is used to train a classifier. For some input x, each classifier will produce a vector that conveys the degree of confidence that the classifier has for each class given the input.

They then discuss DS. DS is said to represent uncertainties better than probabilistic techniques such as Bayesian. For classifier combination, they stress this is important since there usually exists "a certain level of uncertainty associated with the performance of each classifier". Other classifier combination methods that use DS theory do not accurately estimate the evidence of classifiers, they state and believe that their approach which uses gradient descent learning minimizes the MSE between the combined output and target output of the training set.

They then go into detail about the math behind DS and about their approach.

Note DS Belief and Plausibility formulas from wikipedia:

Belief:

Plausibility:

Note DS Rule of combination:


where:



I need to return to this to describe their method. It is detailed and involves a lot of math.

Why am I reviewing this document. Well, this is a little off topic but I thought any exposure to methods that use DS will help me understand it better.

Paper Summary - An Introduction to Multisensor Data Fusion

D. L. Hall and J. Llinas, editors. Handbook of Multisensor
Data Fusion. CRC Press, 2001.

This paper is based on the book and gives a general background in multisensor data fusion. It gives basic definitions, a bit of history and highlights types of applications that use multisensor data fusion techniques. This is most prevalent in military applications but commercial applications are also making use of fusing data from multiple sources. There are advantages in using a 'multi-sensor' approach, improved accuracy and estimates are better and in general there is a statistical advantage.

It goes on to provide some basic definitions and discusses examples of sensors (more related to military domain). What is interesting is the following:

"The most fundamental characterization of data fusion involves a hierarchical transformation between observed energy or parameters (provided by multiple sources as input) and a decision or inference (produced by fusion estimation and/or inference processes) regarding the location, characteristics, and identity of an entity, and an interpretation of the observed entity in the context of a
surrounding environment and relationships to other entities....
The transformation between observed energy or parameters and a decision or
inference proceeds from an observed signal to progressively more abstract concepts."

They go on to discuss methods which are to make identity estimations including Dempster-Shafer and Bayesian.

"Observational data may be combined, or fused, at a variety of levels from the raw data (or observation) level to a state vector level, or at the decision level."

It then talks in details about examples in military and non-military applications and then about the Joint Data Fusion Process Model which was established in 1986.

The rest of the paper goes into detail about the architecture.

Why is this important to my work?

There are aspects about true multi-sensor data fusion that can be adapted and used in fusing semantic web data. There are very similar issues involved. We get data about entities from different sources. This data can be complementary, certain sources can offer facts that other sources are not aware of and fusing this information together presents a more comprehensive picture of an entity. This is applicable which smushing FOAF instances (part of earlier work) and this is applicable which simply merging fact retrieved from different sources. One example in particular is new sources. Different facts can be exposed from different news sources. When you bring these facts together you get a more complete story.

This brings us to another issue with data fusion and that is conflict resolution. When we are combining sources sometimes the information can be in conflict with each other. This is an interesting problem.

This paper is a great way to get a good background in multi-sensor data fusion and one can use definitions, techniques, architectures and apply them to fusing Semantic Web data.

Tuesday, April 20, 2010

Peers

"Travel only with thy equals or thy betters; if there are none, travel alone." --The Dhammapada

Sunday, April 18, 2010

Commitment

"Until one is committed, there is hesitancy, the chance to draw back, always ineffectiveness. Concerning all acts of initiative and creation, there is one elementary truth, the ignorance of which kills countless ideas and splendid plans: that the moment one definitely commits oneself, then providence moves too. All sorts of things occur to help one that would never otherwise have occurred. A whole stream of events issues from the decision, raising in one’s favor all manner of unforeseen incidents and meetings and material assistance, which no man could have dreamed would have come his way. Whatever you do, or dream you can, begin it. Boldness has genius, power and magic in it. Begin it now." --Johann Wolfgang von Goethe (1749- 1832)

Saturday, April 17, 2010

Paper Summary - An Introduction to Bayesian and Dempster-Shafer Data Fusion

D. Koks and S. Challa, DSTO Systems Sciences Laboratory, November 2005
http://www.dsto.defence.gov.au/publications/2563/DSTO-TR-1436.pdf

This paper is about data fusion and using techniques such as Bayesian and DS. It starts out with an introduction about data fusion and how it is defined in multiple domains. It then highlights work by others that implemented different methods to perform data fusion. It then gives nice detailed examples of using Bayesian and Dempster-Shafer to perform data fusion. It ends with a comparison summary of these two techniques.

The paper is very good. It shows all of the equations step by step and gives clear examples. It very clearly shows shortcoming of both methods.

Notes on XMPP Prototype

I've been recently investigating XMPP for Cloud Computing. After reading the specifications and learning basically what it is all about, I've begun working on a prototype that would accomplish similar tasks that I accomplish with mesh4x . Basically the goal is offline/online synchronization. So far, I've played around with Jabber, tigase, and a couple of other servers. I need basically server and client support. So far, I like OpenFire and Smack. Right now I have code written in Java that basically creates a chat between two users. I created two accounts at jabber.iitsp.com and wrote some basic code. Now, my two clients are communicating by chatting with one another.

My next steps:
  1. Use OpenFire locally as the server
  2. Write code that will do what I do with mesh4x
  3. Hook it into Google Maps



Basic code:

XMPPConnection connection = new XMPPConnection("jabber.iitsp.com");
connection.connect();
connection.login(userName, password);
Chat chat = connection.getChatManager().createChat(person, new MessageListener() {

public void processMessage(Chat chat, Message message) {
System.out.println("Received message: " + message.getBody());
}
});

chat.sendMessage("Hi there!");

I do a bit more in my code to keep the thread running and to recognize who the user is and respond with a customized message but this is the code that actually sends and receives the message. This is taken from the Smack documentation as a basic test. If you want to just test it one way, create an account at Trillian using XMPP as the protocol with one of your user accounts: user1@jabber.iitsp.com. Then set up your Java code as user2 who wants to send to user1. Your trillian client will pop up your message.

Monday, April 5, 2010

Paper Summary - Ontology matching: A machine learning approach

A. Doan and J. Madhaven and P. Domingos and A. Halevy, "Ontology matching: A machine learning approach", Handbook on Ontologies in Information Systems,2004,397-416, Springer-Verlag


This paper is about finding mappings between ontologies and discusses the system GLUE. Using learning techniques it semi-automatic generates mappings. This work attempts to address the issue of matching concept nodes.

It begins by discussing the meaning of similarity and a discussion around using the joint probability distribution of concepts.

It then discusses the complexities of computing the JPD for two different concepts.

It then discusses using machine learning to use instances of one concept to learn a classifier for that concept and the same for the second concept.

Rather than a single algorithm is uses multiple algorithms and then combines their predictions.

This paper is long. Their techniques are novel and interesting. This is a good paper to use for machine learning techniques for instance matching.

Saturday, April 3, 2010

Paper Summary - Probabilistic relational models

D. Koller. Probabilistic relational models. In S. Dzeroski and P. Flach, editors, Proceedings of Ninth International Workschop on Inductive Logic Programming (ILP-
1999). Springer, 1999.


This paper highlights deficiencies that exist with Bayesian networks; mainly that BNs cannot represent complex domains because they cannot represent models of domains that they are not aware of in advance. They present probabilistic relational models as a language for describing probabilistic models. Entities, their properties and relations are represented with the language.

The key points in this paper are:


  • BNs are very useful and have been successful as a way to perform probabilistic reasoning
  • BNs are inadequate for representing large complex domains

  • BNs lack the concept of an object and therefore there is no concept of similarity among objects across contexts

  • Probabilistic relational models extend BNs by adding concepts of individuals, properties and relations




Objects are the 'basic entities' in a PRM and partitioned into disjoint classes with a set of associated attributes. In addition to objects, relations also make up the vocabulary. It states that the goal of the PRM is to define a probability distribution over a set of instances for a schema.

The key distinctions here with PRMs and Bayesian networks are PRMs define the dependency model at the class level and they use the relational structure of the model. They are more expressive then Bayesian networks.

Regarding inference, they show how this expressiveness helps rather than further complicates the processing.

The paper is dense but interesting.

Tuesday, March 30, 2010

Paper Summary - Data Mining: An Overview from a Database Perspective

M. Chen and J. Han and P. Yu, "Data Mining: An Overview from a Database Perspective", IEE Transactions on Knowledge and Data Engineering, 8(6): 866-883, 1996

This is a seminal paper about mining information from large databases. It is a survey of data mining techniques from a database researcher perspective.

The paper discusses key feature and challenges:


  • Different types of data
  • Efficiency and Scalability of algorithms
  • Accuracy and usefulness of results
  • How results are conveyed
  • Multiple Abstraction Levels
  • Mining different sources
  • Privacy and security



They go on to classify different types of data mining schemes. They can be classified according to the data they are examining, according to the kind of knowledge they are mining, and according to the technique they implore. This paper focuses on the knowledge they are mining.


  • Association rules
  • Data Generalization and Summarization
  • Classification huge amount of data
  • Data Clustering
  • Pattern based similarity
  • Path traversal patterns


It describes each one of this items in great detail. The paper is a great paper to get a good foundation on this topic. It is quite long but detailed. I don't seem mention of confidence approach.

Paper Summary - Link-based text classification

Q. Lu and L. Getoor, "Link-based text classification",IJCAI workshop on text-mining and link-analysis, 2003

This paper examines machine learning when objects are linked and using the links as additional information for the classifier. They present a framework which models link distributions using a logistic regression model for both content and links. They found that using links actually improved the accuracy of the classifier.

They use an iterative classification algorithm since the attributes can be correlated. There is a joint distribution between links and content attributes.

The main points in the paper are:

* The statistical framework models link distributions
* They show through results how this improved accuracy of the classifier
* They show an evaluation of the iterative categorization algorithm

Paper Summary - Unsupervised named-entity extraction from the web: An experimental study

"Unsupervised named-entity extraction from the web: An experimental study", O. Etzioni and M. Cafarella and D. Downey and S. Kok and A. Popescu and T. Shaked and S. Soderland and D. Weld and A. Yates, Artificial Intelligence,91-134,2005

This paper describes a system that uses an unsupervised approach at entity extraction. It describe the architecture of the system and defines general principles for extraction. They present 3 ways improve recall and extraction without compromising precision:
Pattern Learning - domain-specific
Subclass Extraction - identifies sub-classes
List Extraction - locates lists of class instances

The paper starts with a motivation for using an unsupervised approach. It provides background in information extraction and some of the complexities involved. KNOWITALL uses extraction patterns and pointwise mutal information statistics calculated from the web using hit counts measuring degree of correlation between pairs of words. The PMIs are used as features for a classifier. It consumes information from search engines.

It uses a bootstrapping method which is a set of predicates. Labels are given for each class and symbolic names are given for each class. The Bootstrapper "uses the labels to instantiate extraction rules". The Extractor formulates queries to send to search engine and the Assessor evaluates the extractions.

The paper is quite extensive and describes the system well. Overall this paper is a good read and provides a number of tidbits for new ideas.

Thursday, March 18, 2010

Paper Summary - Performing Object Consolidation on the Semantic Web Data Graph

Hogan, A.; Harth, A.; and Decker, S. 2007. Performing object
consolidation on the semantic web data graph. In In Proceedings
of I3: Identity, Identifiers, Identification. Workshop at 16th
International World Wide Web Conference (WWW2007).

This paper describes identities and the integration of data. They present a method for merging instances across multiple data sources (**large scale**). They describe how they determine two instances represent the same entity using inverse functional properties. Their dataset includes over 72 million instances (wow).

Key points:

  • There isn't much agreement on use of common URIs to identify entities (optional in RDF) so URI represents multiple instances at times
  • There is a lack of formal specification for determining equivalences among entities
  • Existing methods that perform object consolidation rely upon probabilistic methods
  • The use of inverse functional properties in the Semantic Web world is widely used





Paper Summary - On Searching and Displaying RDF Data from the Web

A., H., and H., G. 2005. On searching and displaying RDF data
from the web. In Proceedings of Demos and Posters of the 2nd
European Semantic Web Conference.

This document describes an application built to show RDF in a user interface. It describes how it gathered the data and also a smushing technique it used. The goal was to determine if it was feasible to integrate data without an underlying ontology. They describe their challenges with the data in this paper.

The key points of this paper:


  1. To determine if it is possible to integrate data without using an underlying ontology to do so
  2. They describe their data retrieval process
  3. They describe how they smush data
  4. They describe their application and how they make this data available for a user interface


The paper is short and missing a lot of details. Though I referenced this in the "A Machine Learning Approach to Linking FOAF Instances" document, it really was just to give an example of a smushing process.

Wednesday, March 3, 2010

Paper Summary - Semantics for the Semantic Web: The Implicit, the Formal and the Powerful

A. Sheth, C. Ramakrishnan, and C. Thomas. Semantics for the semantic web: The implicit, the
formal, and the powerful. Semantic Web and Information Systems, 1(1), Idea Group, 2005.

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.83.9929&rep=rep1&type=pdf

This paper discusses both the limitation of relying upon just description logics and the need to utilize different semantics to handle the complexity of exploiting semantic web data. In particular it organizes these semantics into three categories:
  • Implicit - from Patterns in the data, examples include co-occurrence and links
  • Formal - formal language which presents syntactical rules, Description Logic falls under this category
  • Powerful - statistical analysis that uses patterns in the data

What is interesting about this paper are the following statements:

"Even though it is desirable to have a consistent knowledge base, it becomes impractical as the size of the knowledge base increases or as knowledge from many sources is added. It is rare that human experts in most scientific domains have a full and complete agreement. In these cases it becomes more desirable that the system can deal with inconsistencies."

"Sometimes it is useful to look at a knowledge base as a map. This map can be partitioned according to different criteria, e.g. the source of the facts or their domain. While on such a map the knowledge is usually locally consistent, it is almost impossible and practically infeasible to maintain a global consistency. Experience in developing the Cyc ontology demonstrated this challenge. Hence, a system must be able to identify sources of inconsistency and deal with contradicting statements in such a way that it can still produce derivations that are reliable."

They then go on to discuss current approaches to deal with this inconsistency.

  • Probabilistic reasoning
  • Possibilistic reasoning
  • Fuzzy reasoning

It highlights drawbacks with these methods and proposes the need for a standardization in this area.

The paper then discusses correlating semantic capabilities with types of semantics in relation to the bootstrapping and utilization phases.

The last part of this paper discusses information integration, information retrieval and extraction, data mining and analytical applications.

Some of the interesting papers it references:

R. Agrawal, T. Imielinski, and A. N. Swami. Mining association rules between sets of items in large databases. In P. Buneman and S. Jajodia, editors, Proceedings of the 1993.

D. Barbará, H. Garcia-Molina and D. Porter. The Management of Probabilistic Data. IEEE Transactions on Knowledge and Data Engineering, Volume 4 , Issue 5 (October 1992), Pages: 487 - 502

Jochen Heinsohn: Probabilistic Description Logics. UAI 1994: 311-318.
Int’l Journal on Semantic Web & Information Systems, 1(1), 1-18, Jan-March 2005

Hui Han, C. Lee Giles, Hongyuan Zha, Cheng Li, and Kostas Tsioutsiouliklis. "Two Supervised Learning Approaches for Name Disambiguation in Author Citations" , in Proceedings of ACM/IEEE Joint Conference on Digital Libraries (JCDL 2004), pages 296-305, 2004.

Birger Hjorland Information retrieval, text composition, and semantics. Knowledge Organization 25(1/2):16-31, 1998

Vipul Kashyap, Amit Sheth: Semantic Heterogeneity in Global Information Systems: The Role of Metadata, Context and Ontologies, Cooperative Information Systems 1996

M. Kuramochi and G. Karypis. Finding frequent patterns in a large sparse graph. In SIAM International Conference on Data Mining (SDM-04), 2004.

Alexander Maedche, Steffen Staab: Ontology Learning for the Semantic Web. IEEE Intelligent Systems 16(2): 72-79 (2001)

B. Omelayenko. Learning of Ontologies for the Web: the Analysis of Existent approaches. In Proceedings of the International Workshop on Web Dynamics, 2001.

Erhard Rahm, Philip A. Bernstein. A Survey of Approaches to Automatic Schema Matching. In VLDB Journal 10: 4, 2001
Int’l Journal on Semantic Web & Information Systems, 1(1), 1-18, Jan-March 2005

Amit P. Sheth, Sanjeev Thacker, Shuchi Patel: Complex relationships and knowledge discovery support in the InfoQuilt system. VLDB J. 12(1): 2-27 (2003)

J. Townley, The Streaming Search Engine That Reads Your Mind, August 10, 2000. http://smw.internet.com/gen/reviews/searchassociation/

William A. Woods: “Meaning and Links: A Semantic Odyssey”. Principles of Knowledge Representation and Reasoning: Proceedings of the Ninth International Conference (KR2004), June 2-5, 2004. pp. 740-742

Lotfi A. Zadeh. Toward a perception-based theory of probabilistic reasoning with imprecise probabilities. In Journal of Statistical Planning and Inference 105 (2002) 233-264.

Thursday, March 5, 2009

Oracle SqlPlus Error

A remedy to the following error:
ORA-01034: Oracle not available
...shared memory realm does not exist
...

Execute the following commands:
sqlplus /nolog
connect / as sysdba
startup

I have found Oracle on Ubuntu to be a bit hacky. I've been tweaking configuration each day to get a stable instance running. This wasn't a clean install and Oracle states that Ubuntu is an unsupported os. However, with a bit of tweaking and using the directions I provided in a previous post, one can get a fairly stable Oracle instance running.

Thursday, February 26, 2009

Testing CouchDB

If you made it through the installation process and successfully started CouchDB then you could use your browser to get familiar with CouchDB or you could use curl.

I used curl because it is command line driven, fast and gets the job done.

Test access:
curl http://localhost:5984/

A response of {"couchdb": "Welcome", "version": "0.8.0-incubating"} will indicate we are ready.

If you do not get this response then check to make sure Couchdb is running.

You can also go to the browser to double check: http://localhost:5984.

Creating a database:
curl -X PUT http://localhost:5984/mydemodb/

A repsonse of {"ok",true} will indicate that the database was created. If you get an illegal name error then check your database name. Is it all lower case, no spaces, no special characters?

Deleting a database:
curl -X DELETE http://localhost:5984/mydemodb/

Adding data to the database:

Presuming a database was created, create a testdata.dat file with your data. Here is an example:

{
"field1": "value1",
"field2": "value2"
}

Enter the command to save the data:
curl -T testdata.dat -X POST http://localhost:5984/mydemodb/

With a response of:
{"ok": true, "id": "...", "rev":"..."}

Tuesday, February 17, 2009

Installing Oracle on Ubuntu

Ubuntu isn't a supported OS for Oracle so the installation process can be a bit of a challenge. However, I have found a fairly decent reference for exactly what to tweak in order to successfully install Oracle.

This article provides step by step instruction on installing Oracle on Ubuntu. The only additional notes I would add are the following:

1. You will need to export your display before installing.
2. Ignore the glib errors that occur during the installation process.

Enjoy....

Thursday, February 12, 2009

CouchDB

If you are struggling with the installation of CouchDB on Ubuntu, particularly the dreaded SpiderMonkey issue. The process outlined at http://barkingiguana.com/2008/06/28/installing-couchdb-080-on-ubuntu-804 worked perfectly. Blow away your current CouchDB directory first, then follow the process outlined at http://barkingiguana.com/2008/06/28/installing-couchdb-080-on-ubuntu-804 and you will quickly discover success.