Dr. Dror

Foo is not just bar


Hedge Yourself From a Risky Data Science Job

I recently came across a wonderful post by Talia Borodin titled "Think Your Company Needs a Data Scientist? You're Probably Wrong". If you didn't ready it yet, make sure you do it! It contains a wonderful collection of truths that every individual who has anything to do with data science …

  • Sun 10 September 2017
  • Stats

Why do we need to divide by n-1?

Trying to give an intuitive understanding what's the difference between a biased and unbiased estimators of variance of a sample.

Group by date from a column

Assume you have data set as follows: ID Date Value x x x where each row contains an ID, a date (given as pd.Datetime) and a value. The objective is to count how many rows occur in each day. In [1]: import pandas as pd import numpy as np …

  • Thu 22 June 2017
  • ML

Some learnings from implementing a transformer

I had to (or at least I thought I had to) implement a transformer to be used in a sklearn.pipeline.Pipeline. In a nutshell, I implemented badly the transform method. The original version can be found in this gist. In the following version I fixed it. Furthermore, I left …