如何规范PageRank成绩

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PageRank属性计算所有year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，我想根据该年的PageRank分数与论文的平均PageRank分数之间的差异(该年的平均值是基于对year属性具有相同值的所有节点的PageRank分数)来计算一个缩放分数。

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分数？

任何帮助都是非常感谢的！

Answer 1

这个查询应该返回每个year/title组合的year(作为绝对值)(缩放分数越低，标题的page_rank越接近该年的平均值)：

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;

您还可能希望对结果进行排序(例如，通过year或scaled_score)。