Description
In this homework, you will implement a naïve Bayes’ classifier in Matlab, Python, or R. Here are
the steps you need to follow:
1. Read Section 5.7 from the textbook.
2. You are given a multivariate classification data set, which contains 195 handwritten
letters of size 20 pixels × 16 pixels (i.e., 320 pixels). These images are from five distinct
classes, namely, A, B, C, D, and E, where we have 39 data points from each class. The
figure below shows five sample figures from each class. You are given two data files:
a. hw03_data_set_images.csv: letter images,
b. hw03_data_set_labels.csv: corresponding class labels.
3. Divide the data set into two parts by assigning the first 25 images from each class to the
training set and the remaining 14 images to the test set.
4. Estimate the parameters �#!, �#”, �##, �#$, �#%, �&(� = 1), �&(� = 2), �&(� = 3), �&(� = 4), and
�&(� = 5) using the data points you assigned to the training set in the previous step. Your
parameter estimations should be similar to the following figures.
> print(pcd[,1])
[1] 0.00 0.00 0.00 0.04 0.04 0.04 0.16 0.20 …
> print(pcd[,2])
[1] 0.04 0.24 0.24 0.20 0.12 0.08 0.12 0.16 …
> print(pcd[,3])
[1] 0.00 0.00 0.00 0.00 0.00 0.12 0.20 0.24 …
> print(pcd[,4])
[1] 0.12 0.44 0.40 0.16 0.12 0.08 0.08 0.08 …
> print(pcd[,5])
[1] 0.00 0.12 0.12 0.08 0.12 0.16 0.12 0.04 …
5. Draw your �#!, �#”, �##, �#$ and �#% parameter estimations as images.
6. Calculate the confusion matrix for the data points in your training set using the
parametric discrimination rule you will develop using the estimated parameters. Your
confusion matrix should be similar to the following matrix.
y_train
y_predicted 1 2 3 4 5
1 25 0 0 0 0
2 0 24 1 0 1
3 0 0 24 0 0
4 0 1 0 25 0
5 0 0 0 0 24
7. Calculate the confusion matrix for the data points in your test set using the parametric
discrimination rule you will develop using the estimated parameters. Your confusion
matrix should be similar to the following matrix.
y_test
y_predicted 1 2 3 4 5
1 7 0 0 0 0
2 0 11 3 2 4
3 0 0 7 0 0
4 7 3 3 12 0
5 0 0 1 0 10
What to submit: You need to submit your source code in a single file (.m file if you are using
Matlab, .py file if you are using Python, or .R file if you are using R) and a short report
explaining your approach (.doc, .docx, or .pdf file). You will put these two files in a single zip
file named as STUDENTID.zip, where STUDENTID should be replaced with your 7-digit
student number.
How to submit: Submit the zip file you created to Blackboard. Please follow the exact style
mentioned and do not send a zip file named as STUDENTID.zip. Submissions that do not follow
these guidelines will not be graded.
Late submission policy: Late submissions will not be graded.
Cheating policy: Very similar submissions will not be graded.
