be an image feature space, and Based on the image data set V, we can estimate an image instance-to-feature co-occurrence matrix A |V|×|F | ∈ R |V|×|F | , where each element A ij (1 ≤ i ≤ |V| and 1 ≤ j ≤ |F|) in the matrix A is the frequency of the feature f j appearing in the instance be a text feature space.
labeled data are often scarce and expensive to obtain.