What does $\mathbb{R}_{++}$ mean?
I know $\mathbb{R}_+$ means all non-negative real numbers, but I have no clue what $\mathbb{R}_{++}$ means.
What does $\mathbb{R}_{++}$ mean?
I know $\mathbb{R}_+$ means all non-negative real numbers, but I have no clue what $\mathbb{R}_{++}$ means.
It usually means the set of all positive real numbers, $\mathbb{R}_{++} = (0,\infty)$. Of course, there might be more symbols for this set.
From my Course: Probabilistic Methods in Finance, we denoted $R+, R++$ like so: $R+ =\{x\in R : x\ge0\}$ $R++ =\{x\in R : x≫0\}.$
Im not completely sure , but i believe it means strictly positive. Thus not the negative reals NOR zero.
Well assuming the context is real numbers that is.
I believe it is used in countries where R+ is meant to include 0. In most countries R+ does not include 0 , hence the extra symbol.
It might help to read over again to get an idea.