Reranking A process that reorders an initial set of search results by applying additional criteria, so the top results better reflect what is most relevant in context. Reranking typically happens after the initial retrieval step and can factor in signals like user behavior, business rules, or personalization. Definition Definition First, the search engine finds every product that matches the query at all. Then it has to decide what order to put them in, and that's what reranking does. It starts with a basic score based on how closely the words in the query match the product's title or description, then adjusts that order using other factors before showing the results. Those other factors can include how popular a product is, how much profit it makes, whether it's in stock, how often people click it, or how often it actually sells when it shows up for that search. So a product can be a perfect text match for what someone typed and still get pushed down the list if it's out of stock, or pushed up if it tends to sell really well whenever people search that term. This matters because most shoppers only look at the first few results and rarely dig further unless they use a filter. If the right products are in the results but stuck in position 15 instead of position 2, most people will never see them. Reranking fixes the order without changing which products show up in the first place. What it's used for What it's used for It makes sure the products that matter, both to the shopper and to the business, end up where people will actually see them. Without reranking, a store is stuck showing products in whatever order plain text matching produces, which often buries good, well-stocked, well-selling products behind ones that just happen to use similar words. Getting this right means fewer wasted clicks (someone clicking a top result that turns out to be out of stock or not really what they wanted) and more sales straight from the results page, since the products people are most likely to buy are the ones showing up first. How Doofinder applies it Doofinder calls this Relevance Criteria, and it's found under Search > Advanced Preferences > Relevance Criteria in the admin panel. By default, results are sorted by the engine's own relevance score. Store owners can add up to five extra fields as tiebreakers, so if two products score about the same on relevance, the next field, like stock, price, or a custom attribute, decides which one goes first. The recommended approach is to keep relevance score as the main sorting factor, and add business-specific fields after it, so text match still leads and the extra rules only settle close calls. Example Case study Example A home goods store sells three ceramic vases that all match the search "ceramic vase" almost equally well. One is a bestseller with good margins, one is newer with low stock, and one is older and barely sells. Based on text matching alone, all three would show up in about the same spot, with only tiny wording differences deciding the order. After adding stock level and past sales performance as tiebreakers, the bestseller consistently shows up first, the low-stock vase drops slightly so the store doesn't push something that might sell out mid-visit, and the vase that rarely sells ends up near the bottom of that group. Text match still comes first overall, but ties now get settled in the store's favor. References Sources https://support.doofinder.com/search/search-setup/relevance-criteria