关于机器学习:COMP-527机器学习

COMP 527 – 2019 – CA Assignment 1
Data Classification
Implementing Perceptron algorithm
Assessment Information
Assignment Number 1 (of 2)
Weighting 12%
Assignment Circulated 28th January 2019
Deadline 5th March 2018, 15:00 UK Time (UTC)
Submission Mode Electronic via Departmental submission system
Learning outcome assessed (1) A critical awareness of current problems and research
issues in data mining. (3) The ability to consistently apply
knowledge concerning current data mining research issues
in an original manner and produce work which is at the
forefront of current developments in the sub-discipline of
data mining.
Purpose of assessment This assignment assesses the understanding of the Perceptron
algorithm by implementing a binary Perceptron for text
clustering.
Marking criteria Marks for each question are indicated under the corresponding
question.
Submission necessary in order No
to satisfy Module requirements?
Late Submission Penalty Standard UoL Policy.
1
1 Objectives
This assignment requires you to implement the Perceptron algorithm using the Python programming
language.
Note that no credit will be given for implementing any other types of classification
algorithms or using an existing library for classification instead of
implementing it by yourself. However, you are allowed to use numpy library
for accessing data structures such as numpy.array. But it is not a requirement
of the assignment to use numpy. You must provide a README file
describing how to run your code to re-produce your results.
2 Text Classification using Binary Perceptron Algorithm
Download the CA1data.zip file from the COMP 527 web site and uncompress it. Inside, you will
find two files: train.data and test.data, corresponding respectively to the train and test data to be
used in this assignment. Each line in the file represents a different train/test instance. The first
four values (separated by commas) are feature values for four features. The last element is the class
label (class-1, class-2 or class-3).
Questions/Tasks
(1) Explain the Perceptron algorithm for the binary classification case, providing its pseudo code. (20 marks)
(2) Prove that for a linearly separable dataset, perceptron algorithm will converge. (10 marks)
(3) Implement a binary perceptron. (20 marks)
(4) Use the binary perceptron to train classifiers to discriminate between (a) class 1 and class 2,
(b) class 2 and class 3 and (c) class 1 and class 3. Report the train and test classification
accuracies for each of the three classifiers after 20 iterations. Which pair of classes is most
difficult to separate? (20 marks)
(5) For the classifier (a) implemented in part (3) above, which feature is the most discriminative?
(5 marks)
(6) Extend the binary perceptron that you implemented in part (2) above to perform multi-class
classification using the 1-vs-rest approach. Report the train and test classification accuracies
for each of the three classes after training for 20 iterations. (15 marks),
(7) Add an ?2 regularisation term to your multi-class classifier implemented in question (5). Set
the regularisation coefficient to 0.01, 0.1, 1.0, 10.0, 100.0 and compare the train and test
classification accuracy for each of the three classes. (10 marks)
3 Deadline and Submission Instructions
? Submit
2
(a) the source code for all your programs (do not provide ipython/jupyter/colab notebooks,
instead submit standalone code in a single .py file),
(b) a README file (plain text) describing how to compile/run your code to produce the
various results required by the assignment, and
(c) a PDF file providing the answers to the questions.
Compress all of the above files into a single zip file and specify the filename as studentid.tgz
(replace“studentid”by your departmental student id). It is extremely important that you
provide all the files described above and not just the source code! File types other than zip
will not be accepted by the submission system. Every year there is a significant number of
submissions without a student id or a name. Obviously, if you do not write name or student
id then it is not possible to assign marks to you!
Submission is via the departmental submission system accessible from
http://intranet.csc.liv.ac.uk…