public double[] compareCollection(Collection otherCollection) {
		int similarSongCount = 0;
		HashMap<String, Artist> other = otherCollection.getArtists();
		Set<String> keySet = other.keySet();
		Iterator i = keySet.iterator();
		while(i.hasNext()) {
			String tmpName = (String)i.next();
			if(artists.containsKey(tmpName)) {
				Artist tmpArtist = artists.get(tmpName);
				similarSongCount += tmpArtist.compareArtist(other.get(tmpName));
			}
		}
		double[] returnArray = new double[2];
		returnArray[0] = similarSongCount;
		returnArray[1] = (double)similarSongCount / songCount;
		return returnArray;
	}