Mean Average Precision at K is the mean of the average precision at K (APK) metric across all instances in the dataset. APK is a metric commonly used for information retrieval. APK is a measure of the average relevance scores of a set of the top-K documents presented in response to a query. For each query instance, we will compare the set of top-K results with the set of actual relevant documents, that is, a ground truth set of relevant documents for the query.
In the APK metric, the order of the result set matters, in that the APK score would be higher if the result documents are both relevant and the relevant documents are presented higher in the results. It is, thus, a good metric for recommender systems; in ...
