How can reducing page memory size increase download times?
In 2009, YouTube made improvements which reduced the video player from 1.2MB to 98kB. However, the time taken to download the page seemed to increase.
Normalization (z-score for features, Cohen's D for results)
p-values are commonly used to determine if an effect is statistically significant. Cohen's D gives a measure of how important an effect is. It is possible to see a statistically significant difference (p value small) even if the effect isn't...
Goodhard's Law
Goodhart's law claims "When a measure becomes a target, it ceases to be a good measure". This article explores how bad metrics can create perverse incentives, and how cross-validation fails to catch our errors.
Custom Loss vs Custom Scoring
Scikit learn grid search functions include a scoring parameter. Scorers allow us to compare different trained models. Models try to minimize a loss function. While custom scoring is straight-forward, custom losses are not.
Pros and Cons of Changing Definitions
A definition cannot be wrong, but it can fail to be useful. Can you repurpose a definition, or should you start from scratch?
Interview Practice with Precision and Recall
How to prepare for those annoying questions about precision and recall in interviews.
The Bad Names In Classification Problems
There are a proliferation of different metrics in classification problems: accuracy, precision, recall, and more! Many of these metrics are defined in terms of True Positives, True Negatives, False Positives, and False Negatives. Here we give...
What is a ROC Curve? A visualization with credit scores.
ROC (Receiver Operator Characteristic) curves are a great way for measuring the performance of binary classifiers. They show how well a classifier's score (where a higher score means more likely to be in the "positive" class) does at separating...