# Thread: Density of a function

1. ## Density of a function

https://i.imgur.com/uQyGvEN.png

Hi guys,
I need to understand a paper to write my bachelor thesis and the last thing I cannot figure out is how he calculated the density that is shown in this picture.
I would gladly accept some help at this point.
Hope some of you are more intelligent than me and can help me.

2. ## Re: Density of a function

Though I am not completely sure, I guess it is related to the definition of conditional probability. Hope following will help you to clarify somehow.
$P(q|s)=\frac{P(q\cap s)}{P(s)}=\frac{P(q\cap s)P(q)}{P(s)P(q)}=\frac{P(s|q)P(q)}{P(s)}$
Here, $P(q)=\bar{q}$, $P(s)=\frac{2+\bar{q}}{4}$, and $P(s|q)=\frac{2+q}{4}$.