super(dataModel);
this.weighted = weighting == Weighting.WEIGHTED;
this.centerData = centerData;
this.cachedNumItems = dataModel.getNumItems();
this.cachedNumUsers = dataModel.getNumUsers();
this.refreshHelper = new RefreshHelper(new Callable<Object>() {
@Override
public Object call() throws TasteException {
cachedNumItems = dataModel.getNumItems();
cachedNumUsers = dataModel.getNumUsers();
return null;