Interactive simple exponential smoothing

Another interactive demo I created for the courses I teach. This one is about simple exponential smoothing and the main objective is to show the interaction between smoothing parameter and initial level in the fitting and holdout samples. A different interactive demo about exponential smoothing can be found here. A couple of points that may be interesting to observe:

• In-sample and holdout errors do not behave in the same way.
• The error curves can be substantially different for various initial level values.