如何规范PageRank分数

Question

我在一组节点上运行PageRank，其中每个节点都有一个属性year。如何根据year属性计算所有PageRank分数的平均值？也就是说，如果有100个节点总共有20个不同的year值，我想计算20个平均PageRank值。

然后，对于每个节点，我想根据当年论文的PageRank分数和平均PageRank得分之间的差异来计算一个缩放分数(其中，当年的平均值是基于year属性具有相同值的所有节点的PageRanc分数。

运行PageRank的代码是：CALL algo.pageRank.stream( 'MATCH (p:Paper) WHERE p.year < 2015 RETURN id(p) as id', 'MATCH (p1:Paper)-[:CITES]->(p2:Paper) RETURN id(p1) as source, id(p2) as target', {graph:'cypher', iterations:20, write:false, concurrency:20}) YIELD node, score WITH *, node.title AS title,
node.year AS year, score AS page_rank ORDER BY page_rank DESC LIMIT 10000 RETURN title, year, page_rank;

如何更改此代码以返回缩放后的分数？

非常感谢您的帮助！

Answer 1

此查询应返回每个year/title组合的scaled_score(作为绝对值((缩放分数越低，标题的page_rank越接近当年的平均值(：

CALL algo.pageRank.stream(
'MATCH (p:Paper) WHERE p.year < 2015 RETURN id(p) as id',
'MATCH (p1:Paper)-[:CITES]->(p2:Paper) RETURN id(p1) as source, id(p2) as target',
{graph:'cypher', iterations:20, write:false, concurrency:20})
YIELD node, score
WITH 
node.title AS title,
node.year AS year, 
score AS page_rank
ORDER BY page_rank DESC
LIMIT 10000
WITH year, COLLECT({title: title, page_rank: page_rank}) AS data, AVG(page_rank) AS avg_page_rank
UNWIND data AS d
RETURN year, d.title AS title, ABS(d.page_rank-avg_page_rank)/avg_page_rank AS scaled_score;

您可能还需要对结果进行排序(例如，按year或scaled_score排序(。