Suppose a query has a total of 4 relevant documents in the collection. System A and System B have each retrieved 10 documents, and the relevance status of the ranked lists is shown below: System A: [- + – – – – – – – -] System B: [+ + – – – – – – – -]

Suppose a query has a total of 4 relevant documents in the collection. System A and System B have each retrieved 10 documents, and the relevance status of the ranked lists is shown below:

System A: [- + – – – – – – – -]

System B: [+ + – – – – – – – -]

where the leftmost entry corresponds to the highest ranked document, and the rightmost entry corresponds to the lowest ranked document. A “+” indicates a relevant document and a “-” corresponds to a non-relevant one. For example, the top ranked document retrieved by System A is non-relevant, whereas the top ranked document retrieved by B is relevant.

What is the precision at 10 documents of both systems?