The rumor says that Normal distribution is everything.
It will take a long long time to talk about the Normal distribution thoroughly. However, today I will focus on a (seemingly) simple question, as is stated below:
If $X$ and $Y$ are univariate Normal random variables, will $X+Y$ also be Normal?
What’s your reaction towards this question? Well, at least for me, when I saw it I said “Oh, it’s stupid. Absolutely it is Normal.

This title is a bit exaggerating since handwriting recognition is an advanced topic in machine learning involving complex techniques and algorithms. In this blog I’ll show you a simple demo illustrating how to recognize a single number (0 ~ 9) using R. The overall process is that, you draw a number in a graphics device in R using your mouse, and then the program will “guess” what you have input. It is just for FUN.