Rank	Document	Relevant	relevant sum	Precision	Recall
1	d123	1	1
2	d84	0	1
3	d56	1	2
4	d6	0	2
5	d8	0	2
6	d9	1	3
7	d511	0	3
8	d129	0	3
9	d187	0	3
10	d25	1	4
11	d38	0	4
12	d48	0	4
13	d250	0	4
14	d113	0	4
15	d3	1	5

Start with the table of data scores0.xls. This table lists the retrieval of 15 documents. They are listed in the order retrieved thus the first retrieved gets rank 1 and is d_123. It is judged relevant. The second document retrieved is document d84 and it is judged not relevant and so on.

The column "relevant sum" is simply the running total of the relevant documents. Thus at rank 8 (that is eight documents retrieved, 3 of those documents were relevant.

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