9. A non-transitory machine-readable storage medium storing carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform steps comprising: segmenting a search query into one or more units; wherein each unit of the one or more units is an element of a query; for each of the one or more verticals, computing a coverage adjusted log likelihood for the search query; wherein, for each particular vertical of the one or more verticals, the coverage adjusted log likelihood for the particular vertical is a conditional probability of the query appearing in a log of queries previously submitted within the particular vertical given the one or more units; and assigning the search query to a subset of the one or more verticals based in part on the coverage adjusted log likelihood, wherein the step of assigning the search query to a subset of the one or more verticals further comprises the steps of: selecting a highest coverage adjusted log likelihood from coverage adjusted log likelihoods computed for the search query for each of the one or more verticals; computing a set of differences between the highest coverage adjusted log likelihood and each coverage adjusted log likelihood computed for the search query for each of the one or more verticals; and assigning the search query to a subset of the one or more verticals further based at least in part on the set of differences.
13. The non-transitory machine-readable storage medium of claim 9 , wherein the probability that the query belongs to a given vertical is based at least in part on a sum of probabilities of individual units of the query belonging to the given vertical.