Week 9

Hey everyone, done with the second to last week. Just counting down days until the presentation. As promised I have some results for my latest undertaking. The results actually turned out really well, but I am not sure to what extent they will be used.

Just to make sure you guys know what's going on, I'll explain it again. This program is an example of unsupervised learning. I took data that was already labeled (so it's supervised in a sense) and grouped the coughs based on their characteristics. What characteristics you ask? The easiest way to explain it is by just saying frequency, but I'll explain a little more. One thing that is pretty self explanatory is the length of the cough, but otherwise I took a Fourier transform of each cough which gives me the frequencies at multiple points in the cough, 256 of them to be exact.

After getting all that information on the 500 coughs of my sample, I had to do something called principal component approximation, which basically condenses all the information. I ended up with a 257x257 matrix to perform k-means on. In MATLAB there is actually a built in function for k-means, so most of the coding I did was to make the graph all pretty for you guys.

This is the graph that looks the best. I took two of the columns from the 257x257 matrix and graphed it. This is just the first two columns, but I also randomized the columns later, and got slightly uglier results. The way K-means works, the groups should be different every time, but this graph was pretty clear with the groups.

A lot of you asked last week, what's the importance of doing k-means, and I answered you briefly, but I thought this is a good chance to explain better. With the groups I created we can make a guess as to which coughs are similar to each other. This may not seem too important right now, but when we merge samples from all types of people possibly with diagnosed illnesses we can start relating the coughs to an illness.

Well that's it for this week. I've made some good progress making my final presentation and I still have some more stuff to do in this last week, so look forward to that. I know a lot of you have finals, mocks and APs coming up, so good luck, and ... Buh Bye.