1. A computer-implemented method comprising: with a processor-based data importing module, importing data representing a plurality of search result sets resulting from a plurality of executed search queries, each search result set including a plurality of item listings satisfying a search query from the plurality of executed search queries and a listing slot identifier identifying a position within a search results page of a particular item listing that has resulted in a transaction being concluded, the listing slot identifier determined utilizing a production scoring function specified with one or more parameters that are weighted with weighting factors; with a processor-based parameter optimization module, processing the plurality of search result sets to derive a new scoring function, the new scoring function having one or more weighting factors for one or more parameters, the one or more weighting factors selected to satisfy a set of constraints; and with a processor-based scoring function evaluation module, evaluating the performance of the new scoring function relative to a production scoring function.