Machine Learning
10-701/15-781, Fall 2011Eric Xing School of Computer Science, Carnegie-Mellon University |
Course Project
Your class project is an opportunity for you to explore an interesting multivariate analysis problem of your choice in the context of a real-world data set. Projects can be done by you as an individual, or in teams of two to three students. Each project will also be assigned a 701 instructor as a project consultant/mentor. Instructors and TAs will consult with you on your ideas, but of course the final responsibility to define and execute an interesting piece of work is yours. Your project will be worth 20% of your final class grade, and will have 4 deliverables:
- Proposal:1 page (10%), Due: 10/17
- Midway Report:3-4 pages (20%), Due: 11/14
- Final Report: 8 pages (40%) Due: 12/8 @ midnight by email to the instructor list
- Poster
Presentation :
(30%), on 12/8 in NSH atrium from 2:30 pm to 6:30 pm
Note that all write-ups in the form of a NIPS paper. The page limits are strict! Papers over the limit will not be considered.
Project Proposal
You must turn in a brief project proposal (1-page maximum). Read the list of available data sets and potential project ideas below. You are highly recommended to use one of these data sets, because we know that they have been successfully used for machine learning in the past. If you have another data set you want to work on, you can discuss it with us. However, we will not allow projects on data that has not been collected, so you have to work on existing data sets. It is also possible to propose a project on some theoretical aspects of machine learning. If you want to do this, please discuss it with us. Note that even though you can use data sets you have used before, you cannot use as class projects something that you started doing prior to the class.
Project proposal format: Proposals should be one page maximum. Include the following information:
- Project title
- Data set
- Project idea. This should be approximately two paragraphs.
- Software you will need to write.
- Papers to read. Include 1-3 relevant papers. You will probably want to read at least one of them before submitting your proposal
- Teammate: will you have a teammate? If so, whom? Maximum team size is two students. We expect projects done in a group to be more substantial than projects done individually.
- November 14th milestone: What will you complete by November 14th; Experimental results of some kind are expected here. You should also describe what portion of the project each partner will be doing.
Midway Report
This should be a 3-4 pages short report, and it serves as a check-point. It should consist of the same sections as your final report (introduction, related work, method, experiment, conclusion), with a few sections `under construction'. Specifically, the introduction and related work sections should be in their final form; the section on the proposed method should be almost finished; the sections on the experiments and conclusions will have whatever results you have obtained, as well as `place-holders' for the results you plan/hope to obtain.
Grading scheme for the project report:
- 70% for proposed method (should be almost finished)
- 25% for the design of upcoming experiments
- 5% for plan of activities (in an appendix, please show the old one and the revised one, along with the activities of each group member)
Final Report
Your final report is expected to be a 8-page report. You should submit both an electronic and a hardcopy version for your final report. It should roughly have the following format:
- Introduction - Motivation
- Problem definition
- Proposed method
- Intuition - why should it be better than the state of the art?
- Description of its algorithms
- Experiments
- Description of your testbed; list of questions your experiments are designed to answer
- Details of the experiments; observations
- Conclusions
Poster Presentation
We will have all projects presenting a poster on : 12/8 in the NSH atrium, from 2:30 pm to 6:30 pm . At least one project member should be present during the
poster
hours. The session will be open
to everybody.
Project Suggestions:
Ideally, you will want to pick a
problem in a
domain of your interest, e.g., natural language parsing, DNA sequence
analysis, text
information retrieval, network mining, reinforcement learning, sensor
networks, etc., and formulate
your problem using machine learning techniques. You can then, for
example, adapt
and tailor standard
inference/learning algorithms to your problem, and do a thorough
performance
analysis. You
can also find some project ideas below.
Educational Data Mining on Predicting Student Performance
Data:
Register at the KDD Cup 2010: Educational Data Mining Challenge website, and click on "Get Data".There are two types of data sets available, development data sets and challenge data sets. Development data sets differ from challenge sets in that the actual student performance values for the prediction column, "Correct First Attempt", are provided for all steps.
The data takes the form of records of interactions between students and computer-aided-tutoring systems. The students solve problems in the tutor and each interaction between the student and computer is logged as a transaction. Four key terms form the building blocks of the data. These are problem, step, knowledge component, and opportunity.
Project idea: How generally or narrowly do students learn? How quickly or slowly? Will the rate of improvement vary between students? What does it mean for one problem to be similar to another? It might depend on whether the knowledge required for one problem is the same as the knowledge required for another. But is it possible to infer the knowledge requirements of problems directly from student performance data, without human analysis of the tasks? We would like to ask you to predict whether a student is likely to be correct or not on each step given based on previous log data. The problem can be formalized as a classification problem. You could also build a model of students' learning behavior and predict the probability of making an error. The challenge here is to select the correct classifier/model that best represents the data. Moreover, maybe not all given features are informative. Models that are over-complicated may overfit. How to find the relevant features and make good use of them are interesting topics.
References::
Feature Engineering and Classifier Ensemble for
KDD Cup 2010,
Yu et al., 2010
Using HMMs and bagged decision trees to leverage rich features
of user and skill from an intelligent tutoring system dataset,
Pardos and Heffernan, 2010
Collaborative
Filtering Applied to Educational Data Mining, Toscher and
Jahrer, 2010
Inferring Networks of Diffusion and Influence
Data:
Download the data at http://snap.stanford.edu/netinf/#data.Data contains information about the connectivity of the who-copies-from-whom or who-repeats-after-whom network of news media sites and blogs inferred by NETINF, an algorithm that infers a who-copies-from-whom or who-repeats-after-whom network of news media sites and blogs.
The dataset used by NETINF is called MemeTracker. It can be downloaded from here.
MemeTracker contains two datasets. The first one is a phrase cluster data. For each phrase cluster the data contains all the phrases in the cluster and a list of URLs where the phrases appeared. The second is the raw MemeTracker phrase data, which contains phrases and hyper-links extracted from each article/blogpost.
Project idea: Information diffusion and virus propagation are fundamental processes taking place in networks. In many applications, the underlying network over which the diffusions and propagations spread is hard to find. Finding such underlying network using MemeTracker data would be an interesting and challenging project. Gomez-Rodriguez et al. (2010) have recently published a paper on this topic, and made their code publically accessible. It would be interesting to replicate their result and further improve the proposed algorithm by making use of more informative features (e.g., textual content of postings etc).
References::
Inferring Networks of Diffusion and Influence,
Gomez-Rodriguez et al., 2010
Apply NetInf to Other Domains
Data:
Download the data at http://snap.stanford.edu/netinf/#data.Data contains information about the connectivity of the who-copies-from-whom or who-repeats-after-whom network of news media sites and blogs inferred by NETINF, an algorithm that infers a who-copies-from-whom or who-repeats-after-whom network of news media sites and blogs.
The dataset used by NETINF is called MemeTracker. It can be downloaded from here.
MemeTracker contains two datasets. The first one is a phrase cluster data. For each phrase cluster the data contains all the phrases in the cluster and a list of URLs where the phrases appeared. The second is the raw MemeTracker phrase data, which contains phrases and hyper-links extracted from each article/blogpost.
Project idea: In Gomez-Rodriguez et al.'s (2010) paper, they applied NetInf to Memetracker, and found that clusters of sites related to similar topics emerge (politics, gossip, technology, etc.), and a few sites with social capital interconnect these clusters allowing a potential diffusion of information among sites in different clusters. It would be interesting to see how the proposed algorithm could be used in other networks, and what knowledge could we get from those networks. For example, can we discover users that share similar interest from a social network? Network datasets of different domains can be found at here. Different networks may take different forms, and thus the algorithm may not be directly applicable. How to modify the existing algorithm to support other networks?
References::
Inferring Networks of Diffusion and Influence,
Gomez-Rodriguez et al., 2010
Dynamically Inferring Networks of Diffusion and Influence
Data:
Download the data at http://snap.stanford.edu/netinf/#data.Data contains information about the connectivity of the who-copies-from-whom or who-repeats-after-whom network of news media sites and blogs inferred by NETINF, an algorithm that infers a who-copies-from-whom or who-repeats-after-whom network of news media sites and blogs.
The dataset used by NETINF is called MemeTracker. It can be downloaded from here.
MemeTracker contains two datasets. The first one is a phrase cluster data. For each phrase cluster the data contains all the phrases in the cluster and a list of URLs where the phrases appeared. The second is the raw MemeTracker phrase data, which contains phrases and hyper-links extracted from each article/blogpost.
Project idea: In Gomez-Rodriguez et al.'s (2010) paper, the proposed algorithm currently considers static propagation networks. But real influence networks are dynamic. Is it possible to detect such networks?
References::
Inferring Networks of Diffusion and Influence,
Gomez-Rodriguez et al., 2010
Relational Information Retrieval
Data:
2010, yeast2 updated yeast data with extra information about Mesh heading, chemicals and affiliations etc. (321K entities and 6.1M links)
2010, fly a biological literature graph with 770K entities and 3.5M links
2010, yeast a biological literature graph with 164K entities and 2.8M links
All these datasets are relational graph based datasets. Nodes in the graph are of different types (e.g. author, paper, gene, protein, title word, journal, year). Edges between nodes describe relations between two nodes (e.g. AuthorOf, Cites, Mentions).Project idea: Scientific literature with rich metadata can be represented as a labeled directed graph. Given this graph, can we suggest related work to authors? Can we retrieve relevant papers given some key words? All of these tasks can be formulated as relational retrieval tasks in the graph. How to efficiently retrieve items in the graph given some specific nodes as queries? Random walk with restart (RWR) has been used to model these tasks. Pontential projects include implementing different versions of RWR related work, and further improving them to achieve better retrieval quality. References::
Ni Lao, William W. Cohen, Relational retrieval using a combination of path-constrained random walks Machine Learning, 2010, Volume 81, Number 1, Pages 53-67 (ECML, 2010 slides poster )
Image Categorization
Project idea: Image categorization/object
recognition has been one of the most important research problems
in the computer vision community. Researchers have developed a
wide spectrum of different local descriptors, feature coding
schemes, and classification methods.
In this project, you will implement your own object recognition
system. You could use any code from the web for computing image
features, such as SIFT, HoG, etc.
For computing SIFT features, you could use http://www.vlfeat.org/~vedaldi/code/sift.html.
Following is a list of data sets you could use.
A list of datasets:
[2] The PASCAL Object Recognition Database Collection:http://pascallin.ecs.soton.ac.uk/challenges/VOC/databases.html
[3] LabelMe:http://labelme.csail.mit.edu/
[4] CMU face databases:http://vasc.ri.cmu.edu/idb/html/face/
[5] Face in the wild:http://vis-www.cs.umass.edu/lfw/
[6] ImageNet:http://www.image-net.org/index
[7] TinyImage:http://groups.csail.mit.edu/vision/TinyImages/
Human Action Recognition
Project idea: Applications such as surveillance, video
retrieval and human-computer interaction require methods for
recognizing human actions in various scenarios.
In this project, you will implement your own human action
recognition system. You could use any code from the web for
computing spatio-temporal features. One good example is the
spatio-temporal interest point proposed by Piotr Dollar. Source
code available at http://vision.ucsd.edu/~pdollar/research/research.html.
Following is a list of data sets you could use.
A list of datasets:
[2] Weizmann:http://www.wisdom.weizmann.ac.il/~vision/SpaceTimeActions.html
[3] Hollywood Human Actions dataset:http://www.irisa.fr/vista/Equipe/People/Laptev/download.html
[4] VIRAT Video Dataset:http://www.viratdata.org/
Single Class Object Detector
Project idea:
Given a random photo shot of a bookcover, movie poster, wine bottle
picture, etc, which may have light, scale, angle variation, find
the standard image of the poster, logo, etc, in a database that
matches the query. This is real application for an iPhone user to
identify what they see. For example, if I see a movie poster, or
a bookcover, or a wine bottle, I can take a picture and then
hit search, and find online information of the original image and
other relevant information of the movie, book, and wine.
One intuition here lies in the fact that there are limited number
of books in the world. If we have a database containing all book
covers in the world, the recognition problem would reduce to a
duplicate detection problem, which is much simpler to solve,
compared with general purpose object recognition.
In this project, you are encouraged to design an object detector
for a single image class using duplicate detection. For example,
in the book cover case, you could crawl all pages about books from
Amazon.com and store the images as your database of book covers.
Following is a list of possible image classes you could consider
in this fashion:
[1] Book cover
[2] Landmark (e.g., Eiffel Tower, Great Wall, White House, etc)
[3] Movie Posters (e.g., crawl images fromhttp://www.movieposter.com)
[4] Wine/beer bottle labels
[5] Logos
[6] Art pieces (e.g., painting, sculpture)
Once you have the
database, recognition / detection could be solved using near
duplicated image detection.
You could use any algorithm or source code on the Internet, e.g.http://www.mit.edu/~andoni/LSH/.
Exploring the image world
Project idea: One important aspect of machine learning and computer vision research is to collect proper data sets. For example, ImageNet (http://www.image-net.org/index) is one of the most promising data sets in the image categorization research.
Flickr has about 3.6 Billion photos. Interested in crawling billions of images and build your own image collection? For this project, you are encouraged to crawl images from websites such as Flickr, twitter, Google Image. We will provide disk space for storage if this becomes necessary.
There has been a long debate in the computer vision community about which of a better algorithm or larger data is more important. That is to say, should we focus on developing more and more sophisticated algorithms, or use simple classification methods, such as Nearest Neighbor classifier, on billions of training images. In this project, you will gather as many images as possible, and deploy simple classification methods on the data set to see if the latter philosophy works.
For crawling images from Flickr, you could refer tohttp://graphics.cs.cmu.edu/projects/im2gps/flickr_code.html as a starting
point.
References::
[1] 80 millions of tiny images. (http://groups.csail.mit.edu/vision/TinyImages/).
Object based action recognition
Project idea: This is a more advanced topic for students interested in cutting-edge research in computer vision. Most actions are associated with objects. For instance, if someone is kicking, holding, or eating, they are doing it to something. Can we recognize actions through objects and vice-versa?
References::
[1] Modeling
Mutual Context of Object and Human Pose in Human-Object
Interaction Activities, Bangpeng Yao and Li Fei-Fei,
CVPR 2010.
Data Mining for Social Media
Project idea: In this project, we encourage students
to infer the underlying relations between different modalities of
information on the Web. Here are some examples.
(1) Given a photo of movie poster (image), can we retrieve related
trailers (video) or latest news articles (documents) of the movie?
To make project simpler, we recommend focusing on less than five movies
(eg. 'Rise of the planet of the apes' and 'The smurfs'). You first download
posters and trailers from some well-organized sites such as imdb.com or itunes.com.
They will be used as training data to learn your classifiers. Now your job is to
gather raw data from youtube.com or Flickr, and classify them. In this project,
we encourage you to explore the possibility to
build classifiers to be learned from one information modality (eg. images),
and to be applicable to other modalities (eg. trailer videos).
(2) Given a beer label (image), can we search for which frames of a given video clip the logo or bottle appears?
Suppose that you are a big fan of Guinness beer. You can easily download the clean
Guinness logo or cup images by Google image search. These images can be used to learn your detector,
which can discover the frames that the logo appears in the video clips.
For testing, you can download some video clips from youtube.com.
The above examples are just two possible candidates, and any new ideas or problem definitions are welcome.
For this purpose, one may take advantage of some source codes
available on the Web as unit modules (eg. near-duplicated image
detection, object recognition, action recognition in video).
Another interesting direction is to improve the current
state-of-the-arts methods by considering more practical scenarios.
Related Papers and Software::
- A good example of how a machine learning technique is
successfully applied to real systems (ex. Google news
recommendation).
[1] Das, Datar, Garg, Rajaram. Google news personalization:
scalable online collaborative filtering. WWW 2007.
- One of most popular approaches to near duplicated image
detection is LSH families.
[2] http://www.mit.edu/~andoni/LSH/
(This webpage links several introductory articles and source
codes).
- Various hashing techniques in computer vision (papers and source
codes).
[3] Spectral Hashing (http://www.cs.huji.ac.il/~yweiss/SpectralHashing/)
[4] Kernelized LSH (http://www.eecs.berkeley.edu/~kulis/klsh/klsh.htm)
- Recognition in video
[5] Naming of Characters in Video (http://www.robots.ox.ac.uk/~vgg/data/nface/index.html)
[6] Action recognition in Video (http://www.robots.ox.ac.uk/~vgg/data/stickmen/index.html)
- Recognition in images
[7] Human pose detection (Poselet) (http://www.eecs.berkeley.edu/~lbourdev/poselets/)
[8] General object detection (http://people.cs.uchicago.edu/~pff/latent/)
Object Recognition, Scene Understanding, and More on Twitter
Project idea: Currently, Twitter does not provide the
photo-sharing functionality, which has been supported by several
third-party services such as twitpic,
yfog, lockerz, instagram. (See the current
market-share on these services at http://techcrunch.com/2011/06/02/a-snapshot-of-photo-sharing-market-share-on-twitter/).
The main goal of this project is to recognize objects or scenes in
user photos by using its contextual information such as author,
taken time, and associated tweets. Students may gather data by
using Twipho or built-in search
engines of the services (eg. http://web1.twitpic.com/search/).
In practice, it is extremely difficult to completely understand the photos in twitter.
Hence, we encourage students to come up with good problem definitions
so that they can not only be solvable as course projects but also be usable to real applications.
Here are some examples.
(1) The photos that are retrieved by querying 'superman' in the
http://web1.twitpic.com/search/
are highly variable. But, given an image, you can build a classifier to tell whether 'superman' logos appear on the images or not.
(2) Let's download the photos queried by 'beach'. Observing the images, you may identify what objects are usually shown.
Choose some of them as our target objects such as human faces, sand, sea, and sky, and learn your classifier for each object category.
Then, your goal is to tell what objects appear where in a twitter image.
Related Papers and Software::
- Some object recognition competition sites will be very helpful.
[1] PASCAL VOC (http://pascallin.ecs.soton.ac.uk/challenges/VOC/)
[2] ImageNet (http://www.image-net.org/challenges/LSVRC/2011/)
[3] MIRFLICKR (http://press.liacs.nl/mirflickr/)
[4] SUN database (http://groups.csail.mit.edu/vision/SUN/)
- Some object detection source codes are available.
[5] Most popular object detection (http://people.cs.uchicago.edu/~pff/latent/)
[6] Object recognition short course ¿ pLSA and Boosting (http://people.csail.mit.edu/torralba/shortCourseRLOC/index.html)
[7] Human pose detection (Poselet)(http://www.eecs.berkeley.edu/~lbourdev/poselets/)
Identifying ancestry-informative markers:
Ancestry informative markers are polymorphisms that differ in frequency across populations. They can be used to differentiate between geographical populations and identify their anestry. This is has an important application in a technique called admixture mapping which can be used to identify polymorphisms that contribute to disease risk in populations. Many collections of ancestry-informative markers have been previously identified using statistical methods for resolving ancestry at the continental level and national level. In this project, you will use the techniques learned in class to identify sets of ancestry-informative markers and compare your results to existing methods.
Data:
- The HapMap project (http://hapmap.ncbi.nlm.nih.gov/) - The International HapMap Project is analyzing DNA from populations with African, Asian, and European ancestry. Together, these DNA samples should enable HapMap researchers to identify most of the common haplotypes that exist in populations worldwide. The DNA samples in the HapMap project come from 1,301 samples from 11 African, European and Asian populations. The data in phase 3 contains the genotype of the individuals at about 1.5 million SNPs. This data can be used for various population genetic analyses.
- The Human Genome Diversity Project (http://www.cephb.fr/en/hgdp/diversity.php) - This project has genetic data from 1050 individuals in 52 world populations. To date, the DNAs have been typed genome wide with almost 1 million SNPs, 843 microsatellites, and 51 small indel loci. Approximately 10,000 CNV (Copy Number Variations) calls from two different laboratories are included in the database.
References:
- Price AL, Butler J, Patterson N, Capelli C, Pascali VL, et al. (2008) Discerning the Ancestry of European Americans in Genetic Association Studies. PLoS Genet 4(1): e236. doi:10.1371/journal.pgen.0030236
- Seldin MF, Price AL (2008) Application of Ancestry Informative Markers to Association Studies in European Americans. PLoS Genet 4(1): e5. doi:10.1371/journal.pgen.0040005
- Tian C, Plenge RM, Ransom M, Lee A, Villoslada P, et al. (2008) Analysis and Application of European Genetic Substructure Using 300 K SNP Information. PLoS Genet 4(1): e4. doi:10.1371/journal.pgen.0040004
Genotype imputation :
Genotype datasets available today include geneotype information at hundreds of thousands or even millions of polymorphisms. However, due to noise or choice of genotyping density, some genotype information in the dataset may be missing. This can cause problems when using the data for further analysis such as association studies, where polymorphisms contributing to disease risk can be identified using the genetic data. The problem of identifying the genotype at these missing positions is called genotype imputation. To accomplish this, various statistical methods are used. In this project, you will use machine learning techniques to identify missing genotype data.
Data:
- The HapMap project (http://hapmap.ncbi.nlm.nih.gov/) - The International HapMap Project is analyzing DNA from populations with African, Asian, and European ancestry. Together, these DNA samples should enable HapMap researchers to identify most of the common haplotypes that exist in populations worldwide. The DNA samples in the HapMap project come from 1,301 samples from 11 African, European and Asian populations. The data in phase 3 contains the genotype of the individuals at about 1.5 million SNPs. This data can be used for various population genetic analyses.
- The Human Genome Diversity Project (http://www.cephb.fr/en/hgdp/diversity.php) - This project has genetic data from 1050 individuals in 52 world populations. To date, the DNAs have been typed genome wide with almost 1 million SNPs, 843 microsatellites, and 51 small indel loci. Approximately 10,000 CNV (Copy Number Variations) calls from two different laboratories are included in the database.
References:
- Zheng, J., Li, Y., Abecasis, G. R. and Scheet, P. (2011), A comparison of approaches to account for uncertainty in analysis of imputed genotypes. Genetic Epidemiology, 35: 102¿110. doi: 10.1002/gepi.20552
- Li Y, Willer CJ, Sanna S, Abecasis GR. Genotype imputation. Annual Review Genomics and Human Genetics 10: 387-406.
Association analysis
Project Idea:The goal of population association studies is to identify patterns of polymorphisms that vary systematically between individuals with different disease states and could therefore represent the effects of risk-enhancing or protective alleles. These studies make use of the statistical correlation between the polymorphism and the trait of interest (usually the presence or absence of disease) to identify these patterns. This project will make use of data from the Personal Genome Project. It contains information about many traits of the individuals from whom the genetic data was obtained. Using techniques such as statistical tests, sparsity-based methods, eigenanalysis, you can try to find the genetic polymorphisms that are likely to be responsible for a particular trait.
Data:
- Personal Genome Project (http://www.personalgenomes.org/) - The Personal Genome Project makes available genetic and phenotypic data from volunteers for analysis. The data can be downloaded at http://www.personalgenomes.org/public/.
References:
- D.J.Balding, (2006) A tutorial on statistical methods for population association studies, Nature Reviews Genetics.
- Stephens M, Balding DJ. (2009) Bayesian statistical methods for genetic association studies, Nature Reviews Genetics.
- Alkes L Price, Nick J Patterson, Robert M Plenge, Michael E Weinblatt, Nancy A Shadick and David Reich, (2006), Principal components analysis corrects for stratification in genome-wide association studies, Nature Genetics.
Using text and network data to predict and to understand
Description:
Many data sets are heterogeneous, comprising feature vectors, textual data (bag of words), network links, image data, and more. For example, Wikipedia pages contain text, links and images. The challenge is figuring out how to use all these types of data for some machine learning task: data exploration, prediction, etc.. A typical machine learning approach to this problem is "multi-view learning", in which the different data types are assumed to be multiple "views" of the entities of interest (webpages in the case of Wikipedia).
Multi-view learning opens up applications not normally available with single-view datasets. For example, consider a citation recommendation service for academics, which suggests papers you should cite based on the text of your paper draft. Such a service would be trained on a corpus of academic papers, learning how the citations relate to the paper texts. Another example would be interest prediction and advertising in social networks: given a user's friend list, determine what things that user is interested in.
In this project, you will focus on datasets with text and network data, such as (but not limited to) citation networks. As our examples suggest, your primary goal is to design a machine learning algorithm that trains on a subset of the text and network data, and, given text (or network links) from test entities, outputs network link (or text) predictions for them. Alternatively, you could design an algorithm that converts text and network data into "latent space" feature vectors suitable for data visualization (similar to methods such as the Latent Dirichlet Allocation and the Mixed-Membership Stochastic Blockmodel). Note that these goals are not exclusive; your proposed method could even do both. The key challenge in this project is figuring out how to learn from text and network data jointly, even though both data types are fundamentally different.
Recommended reading:
- Joint Latent Topic Models for Text and Citations (Nallapati, Ahmed, Xing, Cohen, 2008)
- Multi-view learning over structured and non-identical outputs (Ganchev, Graca, Blitzer, Taskar, 2008)
Suggested Datasets (Provided by Qirong):
- ACL Anthology citation network
- arXiv High-Energy Physics citation network (from KDD cup 2003)
Efficient methods for understanding large networks
Description:
Network data is usually presented as a list of edges, each connecting two network actors. These edges represent binary relationships: for example, in a citation network, a directed edge from paper i to paper j indicates that i cited j. One problem with networks is that the binary relationships are inherently difficult to visualize; a network with thousands of edges is difficult to draw without messy edge overlaps.
In order to visualize network data better, statistical models such as the Mixed-Membership Stochastic Blockmodel (closely related to the Latent Dirichlet Allocation model used in NLP) take binary network relationships, and from them learn individual feature vectors for each actor. These individual feature vectors can be interpreted as "communities" or "roles" in the network, and are often easier to cluster or visualize than the original network edges. Furthermore, these feature vectors naturally serve as input to other machine learning methods (such as logistic regression or Naive Bayes), making them highly useful for projects that require learning from network data as well as "conventional" feature vectors. Unfortunately, there is one big drawback to network models such as MMSB: existing learning algorithms require O(N^2) runtime (where N is the number of actors), making them impractical for larger networks with more than 10,000 actors.
In this project, you are to design a network learning algorithm that (1) turns binary network relationships into individual feature vectors for actors, such that (2) the learning algorithm is practical for networks >= 10,000 actors in size (i.e. runtime should be less than O(N^2)). The underlying network model could be anything; you could use MMSB as a starting point, or even build a new model from non-statistical methods such as SVMs. Ideally, the learnt feature vectors should give insight into the network and its actors, or they should be useful for clustering or prediction tasks.
Recommended Reading:
These papers introduce the idea of a "latent space", in which the individual actor feature vectors lie. The feature vectors in the latent space "generate" the observed network edges, much as the feature vectors in Naive Bayes generate the observed data. You could use the latent spaces described here as the foundation for your algorithm, or come up with your own:
- Mixed Membership Stochastic Blockmodels (Airoldi, Blei, Fienberg, Xing, 2008)
- Theoretical Justification of Popular Link Prediction Heuristics (Sarkar, Chakrabati, Moore, 2010)
Suggested Datasets (Provided by Qirong):
- ACL Anthology citation network
- arXiv High-Energy Physics citation network (from KDD cup 2003)
Project A1: Cognitive State Classification with Magnetoencephalography Data (MEG)
Data:
A zip file containing some example preprocessing of the data into features along with some text file descriptions: LanguageFiles.zipThe raw time data (12 GB) for two subjects (DP/RG_mats) and the FFT data (DP/RG_avgPSD) is located at:
/afs/cs.cmu.edu/project/theo-23/meg_pilot
You should access this directly through AFS space
This data set contains a time series of images of brain activation, measured using MEG. Human subjects viewed 60 different objects divided into 12 categories (tools, foods, animals, etc...). There are 8 presentations of each object, and each presentation lasts 3-4 seconds. Each second has hundreds of measurements from 300 sensors. The data is currently available for 2 different human subjects.
Project A: Building a cognitive state
classifier
Project idea: We would like to build classifiers to
distinguish between the different categories of objects (e.g. tools vs.
foods) or even the objects themselves if possible (e.g. bear vs. cat).
The exciting thing is that no one really knows how well this will work
(or if it's even possible). This is because the data was only gathered
a few weeks ago (Aug-Sept 08). One of the main challenges is figuring
out how to make good features
from the raw data. Should the raw data just be used? Or maybe it should
be first passed through a low-pass filter? Perhaps a FFT should convert
the time series to the frequency domain first? Should the features
represent absolute sensor values or should they represent changes from
some baseline? If so, what baseline? Another challenge is discovering
what features are useful for what tasks. For example, the features that
may
distinguish foods from animals may be different than those that
distinguish tools from buildings. What are
good ways to discover these features?
This project is more challenging and risky than the others because it
is not known what the results will be. But this is also good because no
one else knows either, meaning that a good result could lead to a
possible publication.
Papers to read:
Relevant but in the fMRI domain:
Learning to Decode Cognitive States from
Brain Images,
Mitchell et al., 2004,
Predicting Human Brain Activity Associated with the Meanings of Nouns,
Mitchell et al., 2008
MEG paper:
Predicting
the recognition of natural scenes from single trial MEG recordings of
brain activity, Rieger et al. 2008 (access from CMU domain)
Project A2: Brain imaging data (fMRI)
This data set contains a time series of images of brain activation, measured using fMRI, with one image every 500 msec. During this time, human subjects performed 40 trials of a sentence-picture comparison task (reading a sentence, observing a picture, and determining whether the sentence correctly described the picture). Each of the 40 trials lasts approximately 30 seconds. Each image contains approximately 5,000 voxels (3D pixels), across a large portion of the brain. Data is available for 12 different human subjects.
Available software: we can provide Matlab software for reading the data, manipulating and visualizing it, and for training some types of classifiers (Gassian Naive Bayes, SVM).
Project A: Bayes network classifiers for fMRI
Project idea: Gaussian Naive Bayes classifiers
and SVMs have been used with this data to predict when
the subject was reading a sentence versus perceiving a picture. Both of
these classify 8-second windows of data into these two classes,
achieving
around 85% classification accuracy [Mitchell et al, 2004]. This project
will
explore going beyond the Gaussian Naive Bayes classifier
(which assumes voxel activities are conditionally
independent), by training a Bayes network in
particular a TAN tree [Friedman, et al., 1997]. Issues you'll
need to confront include which features to include (5000 voxels
times 8 seconds of images is a lot of features) for classifier input,
whether to train brain-specific or brain-independent classifiers, and a
number
of issues about efficient computation with this fairly large data set.
Papers to read: "
Learning to Decode Cognitive States from Brain Images",
Mitchell et al., 2004, "
Bayesian Network Classifiers", Friedman et al., 1997.
Project A3: Genetic Sequence Analysis
We don't currently have a specific dataset in mind for this project, but if you're interested we'll help you find one (ask Field).
One of the most interesting, and controversial, areas of modern science is using people's genetic code to predict things like their likelihood of getting heart disease, their athletic prowess, and even their personality and intelligence. The movie Gattaca shows some of the downsides of this technology, but it can also be immensely helpful if a person takes preventive measures. Also, many drugs work better for people with certain genes. Insurance problems notwithstanding, genetic screening will play a huge role in medicine in the coming decades.
This project is not as well-defined as many others, but the idea is to get ahold of genetic data from patients, along with some kind of phenotype marker (like whether they got a disease), and try to find patterns within the genetic code which predict the trait. This area is very exciting because in many cases, people have literally no idea what causal links exist between genes and traits, but finding these links can be a huge boost to both medicine and pure science (by telling scientists which particular gene combinations to examine)
Project A4: Hierarchical Bayes Topic Models
Statistical topic models have recently gained much popularity in managing large collection of text documents. These models make the fundamental assumption that a document is a mixture of topics(as opposed to clustering in which we assume that a document is generated from a single topic), where the mixture proportions are document-specific, and signify how important each topic is to the document. Moreover, each topic is a multinomial distribution over a given vocabulary which in turn dictates how important each word is for a topic. The document- specific mixture proportions provide a low-dimensional representation of the document into the topic-space. This representation captures the latent semantic of the collection and can then be used for tasks like classifications and clustering, or merely as a tool to structurally browse the otherwise unstructured collection. The most famous of such models is known as LDA ,Latent Dirichlet Allocation (Blei et. al. 2003). LDA has been the basis for many extensions in text, vision, bioiformatic, and social networks. These extensions incorporate more dependency structures in the generative process like modeling authors-topic dependency, or implement more sophisticated ways of representing inter-topic relationships.Potential projects include
- Implement one of the models listed below or propose a new latent topic model that suits a data set in your area of interest
- Implement and Compare approximate inference algorithms for LDA which includes: variational inference (Blei et. al. 2003), collapsed gibbs sampling (Griffth et. al. 2004) and (optionally) collapsed variational inference (Teh. et. al. 2006). You should compare them over simulated data by varying the corpus generation parameters --- number of optics, size of vocabulary, document length, etc --- in addition to comparison over several real world datasets.
Papers:
Inference:
- D. Blei, A. Ng, and M. Jordan. Latent Dirichlet allocation. Journal of Machine Learning Research, 3:993–1022, January 2003.
[pdf] - Griffiths, T, Steyvers, M. (2004). Finding scientific topics. Proceedings of the National Academy of Sciences, 101, 5228-5235 2004.
[pdf] - Y.W. Teh, D. Newman and M. Welling. A Collapsed Variational Bayesian Inference Algorithm for Latent Dirichlet Allocation.In NIPS 2006.
[pdf]
Expressive Models:
- Rosen-Zvi, M., Griffiths, T., Steyvers, M., & Smyth, P. The Author-Topic Model for authors and documents.In UAI 2004.
[pdf] - Jun Zhu, Amr Ahmed and Eric Xing. MedLDA: Maximum Margin Supervised Topic Models for Regression and Classification. International conference of Machine learning. ICML 2009.
[pdf] - D. Blei, J. McAuliffe. Supervised topic models. In Advances in Neural Information Processing Systems 21, 2007
[pdf] - Wei Li and Andrew McCallum. Pachinko Allocation: Scalable Mixture Models of Topic Correlations. Submitted to the Journal of Machine Learning Research, (JMLR), 2008
[pdf]
- L. Fei-Fei and P. Perona. A Bayesian Hierarchical Model for Learning Natural Scene Categories. IEEE Comp. Vis. Patt. Recog. 2005. [PDF]
- L. Cao and L. Fei-Fei. Spatially coherent latent topic model for concurrent object segmentation and classification . IEEE Intern. Conf. in Computer Vision (ICCV). 2007 [PDF]
- Ramesh Nallapati, Amr Ahmed, Eric P. Xing, and William W. Cohen, Joint Latent Topic Models for Text and Citations. Proceedings of The Fourteen ACM SIGKDD International Conference on Knowledge Discovery and Data Mining. (KDD 2008) [PDF]
- Erosheva, Elena A., Fienberg, Stephen E., and Lafferty, John (2004). Mixed-membership models of scientific publications," Proceedings of the National Academy of Sciences, 97, No. 22, 11885-11892. [PDF]
- E. Airoldi, D. Blei, E.P. Xing and S. Fienberg, Mixed Membership Model for Relational Data. JMLR 2008. [PDF]
- Andrew McCallum, Andres Corrada-Emmanuel, Xuerui Wang The Author-Recipient-Topic Model for Topic and Role Discovery in Social Networks: Experiments with Enron and Academic Email. Technical Report UM-CS-2004-096, 2004. [PDF]
- E.P. Xing, W. Fu, and L. Song, A State-Space Mixed Membership Blockmodel for Dynamic Network Tomography, Annals of Applied Statistics, 2009. [PDF]
- S. Shringarpure and E. P. Xing, mStruct: A New Admixture Model for Inference of Population Structure in Light of Both Genetic Admixing and Allele Mutations, Proceedings of the 25th International Conference on Machine Learning (ICML 2008). [PDF]
- Amr Ahmed, Eric P. Xing, William W. Cohen, Robert F. Murphy. Structured Correspondence Topic Models for Mining Captioned Figures in Biological Literature. Proceedings of The Fifteenth ACM SIGKDD International Conference on Knowledge Discovery and Data Mining, (KDD 2009) [PDF]
Project B: Image Segmentation Dataset
The goal is to segment images in a meaningful way.
Berkeleycollected three hundred images and
paid students to hand-segment each one (usually each image has multiple
hand-segmentations).
Two-hundred of these images are training images, and the remaining 100
are test
images. The dataset includes code for reading the images and
ground-truth
labels, computing the benchmark scores, and some other utility
functions.
It also includes code for a segmentation example. This
dataset is
new and
the problem unsolved, so there is a chance that you could come up with
the
leading algorithm for your project.
http://www.cs.berkeley.edu/projects/vision/grouping/segbench/
Project ideas:
Project B: Region-Based Segmentation
Most segmentation algorithms have focused on segmentation based on
edges or
based on discontinuity of color and texture. The ground-truth
in
this
dataset, however, allows supervised learning algorithms to segment the
images
based on statistics calculated over regions. One way to do
this
is to
"oversegment" the image
into superpixels (Felzenszwalb
2004,
code available) and merge the superpixels
into larger
segments. Graphical models can be used to represent
smoothness in
clusters, by adding appropriate potentials between neighboring pixels.
In this project, you can address, for example, learning of such
potentials, and inference in models with very large tree-width.
Papers to read: Some segmentation papers from
Project C: Twenty Newgroups text data
This data set contains 1000 text articles posted to each of 20
online newgroups, for a
total of 20,000
articles. For
documentation and download, see this
website.
This data is useful for a variety of text classification and/or
clustering
projects. The "label" of each article is which of the 20
newsgroups it belongs to. The newsgroups (labels) are
hierarchically
organized (e.g., "sports", "hockey").
Available software: The same website provides an
implementation
of a
Naive Bayes classifier
for this text
data. The
code is quite robust, and some documentation is available, but it is
difficult
code to modify.
Project ideas:
EM text classification in the case where you
have labels for some documents, but not for others (see
McCallum
et al,
and come up with your own suggestions)
Project E: Character recognition (digits) data
Optical character recognition, and the simpler digit recognition task, has been the focus of much ML research. We have two datasets on this topic. The first tackles the more general OCR task, on a small vocabulary of words: (Note that the first letter of each word was removed, since these were capital letters that would make the task harder for you.)
http://ai.stanford.edu/~btaskar/ocr/
Project suggestion:
- Use an HMM to exploit correlations between neighboring letters in the general OCR case to improve accuracy. (Since ZIP codes don't have such constraints between neighboring digits, HMMs will probably not help in the digit case.)
Project F: NBA statistics data
This download contains 2004-2005 NBA and ABA stats for:
-Player regular season stats
-Player regular season career totals
-Player playoff stats
-Player playoff career totals
-Player all-star game stats
-Team regular season stats
-Complete draft history
-coaches_season.txt - nba coaching records by season
-coaches_career.txt - nba career coaching records
Currently all of the regular season
Project idea:
- outlier detection on the players; find out who are the outstanding players.
- predict the game outcome.
Project G: Precipitation data
This dataset has includes 45 years of daily precipitation data from the Northwest of the US:
http://www.jisao.washington.edu/data_sets/widmann/
Project ideas:
Weather prediction: Learn a probabilistic model to predict rain levels
Sensor selection: Where should you place sensor to best predict rain
Project H: WebKB
This dataset contains webpages from 4 universities, labeled with whether they are professor, student, project, or other pages.
http://www-2.cs.cmu.edu/~webkb/
Project ideas:
- Learning classifiers to predict the type of webpage from the text
- Can you improve accuracy by exploiting correlations between pages that point to each other using graphical models?
Papers:
Project I: Deduplication
The datasets provided below comprise of lists of records, and the goal is to identify, for any dataset, the set of records which refer to unique entities. This problem is known
by the varied names of Deduplication, Identity Uncertainty and Record Linkage.
http://www.cs.utexas.edu/users/ml/riddle/data.html
Project Ideas:
- One common approach is to cast the deduplication problem as a classification problem. Consider the set of record-pairs, and classify them as either "unique" or "not-unique".
Papers:
Project J: Email Annotation
The datasets provided below are sets of emails. The goal is to identify which parts of the email refer to a person name. This task is an example of the general problem area of Information Extraction.
http://www.cs.cmu.edu/~einat/datasets.html
Project Ideas:
- Model the task as a Sequential Labeling problem,
where each
email is a sequence of tokens, and each token can have either a label
of "person-name" or "not-a-person-name".
Papers: http://www.cs.cmu.edu/~einat/email.pdf
Project K: Netflix Prize Dataset
The Netflix Prize data set gives 100 million records of the form "user X rated movie Y a 4.0 on 2/12/05". The data is available here: Netflix Prize
Project idea:
-
Can you predict the rating a user will give on a movie from the movies that user has rated in the past, as well as the ratings similar users have given similar movies?
-
Can you discover clusters of similar movies or users?
-
Can you predict which users rated which movies in 2006? In other words, your task is to predict the probability that each pair was rated in 2006. Note that the actual rating is irrelevant, and we just want whether the movie was rated by that user sometime in 2006. The date in 2006 when the rating was given is also irrelevant. The test data can be found at this website.
Project L: Physiological Data Modeling (bodymedia)
Physiological data offers many challenges to the machine learning community including dealing with large amounts of data, sequential data, issues of sensor fusion, and a rich domain complete with noise, hidden variables, and significant effects of context.
1. Which sensors correspond to each column?
characteristic1 | age |
characteristic2 | handedness |
sensor1 | gsr_low_average |
sensor2 | heat_flux_high_average |
sensor3 | near_body_temp_average |
sensor4 | pedometer |
sensor5 | skin_temp_average |
sensor6 | longitudinal_accelerometer_SAD |
sensor7 | longitudinal_accelerometer_average |
sensor8 | transverse_accelerometer_SAD |
sensor9 | transverse_accelerometer_average |
2. What are the activities behind each annotation?
The annotations for the contest were:
5102 = sleep
3104 = watching TV
Datasets can be downloaded from http://www.cs.utexas.edu/users/sherstov/pdmc/
Project idea:
- behavior classification; to classify the person based on the sensor measurements
Project M: Object Recognition
The Caltech 256 dataset
contains images
of 256 object categories taken at varying orientations, varying
lighting conditions, and with different backgrounds.
http://www.vision.caltech.edu/Image_Datasets/Caltech256/
Project ideas:
- You can try to create an object recognition system which can identify which object category is the best match for a given test image.
- Apply clustering to learn object categories without supervision
Project N: Learning POMDP structure so as to maximize utility
Hoey & Little (CVPR 04)
show how to
learn the state
space, and parameters, of a POMDP so as to maximize utility in a visual
face
gesture recognition task. (This is similar to the concept of "utile
distinctions" developed in Andrew
McCallum's PhD
thesis.) The goal of this project is to reproduce Hoey's
work in a simpler (non-visual) domain, such as McCallum's driving task.
Project O: Learning partially observed MRFs: the Langevin algorithm
In the recently proposed exponential
family
harmonium model (Welling
et. al., Xing
et. al.), a constructive divergence (CD) algorithm was used
to
learn the
parameters of the model (essentially a partially observed, two-layer
MRF). In
Xing et. al., a
comparison to variational
learning was performed. CD is essentially a gradient ascent algorithm
of which
the gradient is approximated by a few samples. The Langevin method
adds a random
perturbation to the gradient and can often help to get the learning
process out
of local optima. In this project you will implement the Langevin
learning algorithm for Xings dual wing harmonium model, and test your
algorithm
on the data in my UAI paper. See Zoubin
Ghahramanis paper
of Bayesian learning of MRF for reference.
Project P: Context-specific independence
We learned in class that CSI can speed-up inference. In this project, you can explore this further. For example, implement the recursive conditioning approach of Adnan Darwiche, and compare it to variable elimination and clique trees. When is recursive conditioning faster? Can you find practical BNs where the speed-up is considerable? Can you learn such BNs from data?Project Q: Enron E-mail Dataset
The Enron E-mail data set contains about 500,000 e-mails from about 150 users. The data set is available here: Enron Data
Project ideas:
-
Can you classify the text of an e-mail message to decide who sent it?
Project R: More data
There are many other datasets out there. UC Irvine has a repository that could be useful for you project:
http://www.ics.uci.edu/~mlearn/MLRepository.html
Sam Roweis also has a link to several datasets out there:
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