Task: Question Understanding
Input (English): GhostVLAD is an extension of the NetVLAD approach, which we discussed in the previous section. GhostVLAD works exactly similar to NetVLAD except it adds Ghost clusters along with the NetVLAD clusters. So, now we will have a K+G number of clusters instead of K clusters. The Ghost clusters are added to map any noisy or irrelevant content into ghost clusters and are not included during the feature aggregation stage, as shown in Figure 1 (Right side). 
 Question: What is the GhostVLAD approach?
Output (English): Extractive