Managing Query Pipeline Ranking Weights

A Coveo Cloud Platform index uses a number of ranking factors to evaluate the relevance score of each search result for each query. When the search interface sorting is set to Relevance, the search results are presented in descending relevance score order to present the most pertinent items at the top.

The pre-tuned ranking weights used by Coveo Cloud Platform indexes for each of the ranking factor have been optimized over years of experience with a wide variety of indexed content to deliver well balanced out-of-the-box relevance scores in most cases.

You can fine-tune one or more of the pre-tuned ranking factors for a specific query pipeline (see Required Privileges). When you see that the ranking of specific search results is not ideal in a specific search context or case, consider adjusting one or more of the available ranking factors.

Be careful however when making adjustments as by default, all queries going through the pipeline will be affected. Fixing the ranking for a specific context may have undesired effect on other contexts.

Add a condition to each ranking weight rules so they apply only for the more specific context in which you wish to improve relevance.

The following table provides description for the ranking factor that you can tune.

Ranking factor Description

Keyword proximity

When a query includes more than one keyword, by default the relevance score is increased for items in which keywords appear close to each other. The boost increase is inversely proportional to the distance between the keywords in the item.

An item containing keywords appearing side-by-side will have a higher relevance score boost than one containing the keywords dispersed in a paragraph.

Keyword in concepts

The Coveo Cloud Platform uses a linguistic algorithm to create a list of the most important concepts found in an item (see the @sysconcept field). The relevance score is increased for items containing keywords in their concepts.

Item last modification

The relevance score is increased for items with a more recent modification date.

Keyword in summary

The Coveo Cloud Platform uses a linguistic algorithm that relies on term frequency and proximity to create an item summary made of sentences identified to be the most important ones in the item. The relevance score is increased for items containing keywords in their summary.

Keyword frequency

The relevance score is increased for items containing a higher number of occurrences of keywords. The boost increases proportionally to the number of times a keyword appears in an item relative to the number of times it appears in the index.

Keyword in title

The relevance score is increased for items containing keywords in their title. The boost increases as the proportion of title terms matching the query increases.

An item with a title exactly containing the keywords will have a higher relevance score boost than an item with a title containing only one of the keywords.