What does P@1 mean in this scientific article? In this scientific article: Label Filters for Large Scale Multilabel Classification by Alexandru Niculescu-Mizil and  Ehsan Abbasnejad, they use the notations P@1, P@5 and P@10 as the following table shows



I was thinking that they were $p$-values at the beginning, but it somehow doesn't make sense. 
Could someone explain me what this notations mean?

On the same page of the figure (Section 4) in the article, the notation is defined as follows: 

"Following previous work on large scale multilabel classification (Weston et al., 2013; Prabhu and Varma, 2014; Bhatia et al., 2015) we use precision at k (P@k) as the
  evaluation metric. Precision at k is defined as the fraction of true labels among the top k predictions made by the classifier."

