  Dark matter haloes are biased tracers of the underlying dark matter
distribution. We use a simple model to provide a relation between the abundance
of dark matter haloes and their spatial distribution on large scales. Our model
shows that knowledge of the unconditional mass function alone is sufficient to
provide an accurate estimate of the large scale bias factor. Then we use the
mass function measured in numerical simulations of SCDM, OCDM and LCDM to
compute this bias. Comparison with these simulations shows that this simple way
of estimating the bias relation and its evolution is accurate for less massive
haloes as well as massive ones. In particular, we show that haloes which are
less/more massive than typical M* haloes at the time they form are more/less
strongly clustered than formulae based on the standard Press-Schechter mass
function predict.
