Spectral clustering, step by step
How can one relate a seemingly obivous physics concept to linear algebra, and then to a data science problem.
Recent Posts
Pivot a Hive table
There is no built-in pivot function in Hive, but one can still do it with relative ease.
Schema on write v.s. schema on read
A runner’s view on this database concept.
Platt scaling for probability calibration
For classification problems, sometimes we care about the narrative of the predicted scores more than the predicted class. But the predicted scores can not al...
Gradient descent with the right step
Gradient descent is one of the most important tools in machine learning, but how hard can it be?