Pattern Recognition and Neural Networks
The lecture gives an introduction to statistical pattern
recognition, where neural networks and their relation to
statistical classifiers will also be discussed.
News
-
January 27th, 2009: A solution to task 1 a/b is now
available:
-
January 21st, 2009: Starting today it is possible
to register with us for taking the oral exam. Three different
timeframes are available, each consisting of two dates:
- February 9th-10th, 2009
- March 9th-10th, 2009
- March 23th-24th, 2009
Please sign up for one of the date pairs by sending an email
to Jonas Lööf,
stating name, immatriculation number, study direction in addition to
your choosen time.
Idealy to sign up for a certain time, it should be possible
for you to take the exam at any time during the two days. You will be
notified of the exact time when everyone has registered.
-
January 14th, 2009: There was a misprint on todays
exercise sheet regarding the hand in date. The hand in date is
Wednesday January 21st, 2009, and nothing else.
-
January 7th, 2009: Everyone needing a separate
(oral) exam for the course -- Master- and Batchelour students, etc:
Please send an email to Jonas Lööf,
stating:
- Name
- Immatriculation number
- Study direction
- Type of examination needed
- Preferences regarding the date of exam.
-
December 10th, 2008: The portable, resonably fast,
solution to Exercise 4, Problem 2, is now available on our ftp server.
-
December 3rd, 2008: As I mentioned on todays
excercise lesson, if you want to use Netlab to solve the USPS tasks,
you will need an extension that uses log-probabilities as
discriminant. I have updatded the software section on Netlab (below)
with instructions on this.
-
November 19th, 2008: As stated on todays exercise lecture,
the hand-in date of exercise sheet 5 is postponed to the
December 3rd, 2008 - to allow for more time to discuss the solutions
to task 3, as well as the new sheet.
Contents
- basic statistics
- training and learning
- model-free approaches
- neural networks and discriminative training
- error integral: characteristics and estimates
- mixture distributions and cluster analysis
- EM-algorithm and hidden Markov models
- feature extraction and linear mappings
Lecture Notes (Access only permitted within the RWTH domain)
- Overview of i6: Research and Courses
- Lecture Notes (SS 05, English)
-
Lecture Notes (SS 02, German)
- Appendix: Support Vector Machines, Logistic Regression, and Log-linear Models (SS 07, English)
- Appendix: Maximum Entropy (WS 00/01, English)
Software
- Netlab - a Toolbox for Matlab/Octave
The implementation task of exercise sheet four is optional. To solve
the remaining problems (if you choose not to do the implementation)
you can utilize "Netlab", a free Matlab toolbox that also works with
the free software Octave. Netlabs main focus lies on neural networks,
but it also contains (limited) support for Gaussian models. Please
consult the homepage
of Netlab on how to install it. If you don't have access to Matlab,
install Octave; any reasonably new version should work, I have used
version 2.1.73. For windows, binaries are available for download here,
for linux, use the package system of your distribution.
Please note: This is not a complete solution, since this only
implements and trains Gaussian distributions; you will still have to
make the further work of using them for classification, and do the
estimation of the class priors. Furthermore, no covariance pooling is
implemented, but this can be done after the fact (as in Exercise
sheet 4, task 2b.) As a final note, this software implements Gaussian
mixture models. To use as single Gaussian models, you need to set the
parameter ncentres to 1.
To get some of Netlabs functions to work if your using Octave, you
will have to download this file
and put it where Octave can find it. (For instance in the same directory
as the Netlab functions.)
For the USPS task,
in addition to the standard Netlab package, you will need an
extension that uses a logarithm based implementation for Gaussian
models. This extension is available from the Netlab homepage, but
contains a problem/bug, so a fixed version is available on our
ftp server.
- Python
The demo program
in exercise 2 is written in Python, and you will have to have python
installed to run it. On a Windows computer, download and install
this file
from www.python.org (give the default answer to all installation
questions), then you should be able to run the program by double
clicking it. On most Linux computers Python is already installed and
it should be enough to execute the script directly from the command
line; if not consult the documentation of your distribution on how to
install Python. Modern Mac computers already have Python installed,
you can start the script by typing 'python gauss_demo.py' in a
terminal window. Other users will have to download and install the
correct file from the Python homepage.
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