Gradient Descent 101

Gradient Descent is, in essence, a simple optimization algorithm. It seeks to find the gradient of a linear slope, by which the resulting linear line best fits the observed data, resulting in the smallest or lowest error(s). It isĀ THEĀ inner working of the linear functions we get taught in university statistics courses, however, many of us…

Time Series Analysis 101

A time series can be considered an ordered sequence of values of a variable at equally spaced time intervals. To model such data, one can use time series analysis (TSA). TSA accounts for the fact that data points taken over time may have an internal structure (such as autocorrelation, trend, or seasonal variation) that should…

Outliers 101

Data preparation forms a large part of every data science project. Claims go to extremes, stating that 80-95% of the workload for data scientists consists of data preparation. Outlier detection is one of the actions that make up this preparation phase. It is the process by which the analyst takes a closer look at the…