Probability Density Function

I hate the fact that in Romania we weren’t taught probabilities and statistics.

NOTE

For a continuous random variable with PDF $f$, we have $P(a\le x\le b)={\int }_a^{b}f(x)dx$

In probability, a PDF is a function whole value at any given point in the sample space can be interpreted as the relative likelihood that the value of the random variable would be equal to that sample

These functions help model out the distribution of a particular variable, such as the age at which humans die, the height of a population, or suppose bacteria of a certain species typically live 4 to 6 hours. Then you can create a PDF.

For example, Normal Distribution has probability density $f(x)=\frac{1}{\sqrt{w\pi }}{e}^{-x^2/2}$

For a PDF $f(x)$, we need to satisfy the condition $\int f(x)dx=1$.