Data Piques

Jul 20, 2016

Jan 09, 2016

Explicit Matrix Factorization: ALS, SGD, and All That Jazz

In my last post, I described user- and item-based collaborative filtering which are some of the simplest recommendation algorithms. For someone who is used to conventional machine learning classification and regression algorithms, collaborative filtering may have felt a bit off. To me, machine learning almost always deals with some function which we are trying to maximize or minimize. In simple linear regression, we minimize the mean squared distance between our predictions and the true values. Logistic regression involves maximizing a likelihood function. However, in my post on collaborative filtering, we randomly tried a bunch of different parameters (distance function, top-k cutoff) and watched what happened to the mean squared error. This sure doesn't feel like machine learning.

Nov 02, 2015

Intro to Recommender Systems: Collaborative Filtering

I've written before about how much I enjoyed Andrew Ng's Coursera Machine Learning course. However, I also mentioned that I thought the course to be lacking a bit in the area of recommender systems. After learning basic models for regression and classification, recommmender systems likely complete the triumvirate of machine learning pillars for data science.

Oct 06, 2015

Yet Another PhD to Data Science Post (Part III)

This is the final part in my series on going from PhD to Data Science (parts I and II). As previously mentioned, while I was demoing my Insight project at companies, I also spent a good bit of time studying for interviews. The technical areas of study for interviews can …

Sep 29, 2015

Sep 23, 2015

Yet Another PhD to Data Science Post (Part I)

The internet is awash with posts by former PhD students who have succesfully transitioned into data scientist roles in industry (see here, here, here, and tangentially here). I loved reading these posts while studying for job interviews because I felt like the more I saw examples of sucessful transitions, the …

Nov 25, 2014

Oct 06, 2014

Sep 09, 2014

Aug 31, 2014

← Previous Next → Page 2 of 3