If I am not wrong; after reading the Making recommendations paragraph, it looks like the query does make predictions correctly but for opposite order of people(nodes) in the graph.
This can also be seen by looking at the graph image a few paragraphs above the aforementioned paragraph.
I decided to replace the nodes with one another. Matt -> Annie; Annie -> Matt.
If I am not wrong; after reading the Making recommendations paragraph, it looks like the query does make predictions correctly but for opposite order of people(nodes) in the graph.
This can also be seen by looking at the graph image a few paragraphs above the aforementioned paragraph.
I decided to replace the nodes with one another.
Matt -> Annie;Annie -> Matt.