# Shotgun sequence statistics

I trying to understand the statistics behind shotgun sequencing. Below is an excerpt from a book. Can anyone tell what does the below bold sentence mean? I did not understand the interval range and left hand.

The fragments are assumed to be taken at random from the original full-length sequence, so that if end effects are ignored, the left-hand ends of the fragments are independently distributed with a common uniform distribution over [0,G]. This implies that any such left-hand end falls in an interval (x, x+h) with probability h/G and that the number of fragments whose left-hand end falls in this interval has a binomial distribution with mean Nh/G.

• The interval notation $(x, x + h)$ means that something is $> x$ and $< x + h$. In your example, suppose $G = 1$, $x = 0.5$ and $h = 0.1$. Then the interval $(0.5, 0.6)$ if sampling from a uniform distribution is expected to receive a proportion $0.1$ of data (and so forth). – Nick Cox Jan 6 at 13:14