  We consider an exactly solvable model of branching random walk with random
selection, which describes the evolution of a population with $N$ individuals
on the real line. At each time step, every individual reproduces independently,
and its offspring are positioned around its current locations. Among all
children, $N$ individuals are sampled at random without replacement to form the
next generation, such that an individual at position $x$ is chosen with
probability proportional to $\mathrm{e}^{\beta x}$. We compute the asymptotic
speed and the genealogical behavior of the system.
