Question

我正在Paper类型的一组节点上运行PageRank，其中每个节点都有一个属性year。我目前正在使用当年所有论文的PageRank分数的平均和标准偏差，按年份对每个PageRank分数进行归一化。

我想返回每年的前100篇论文（基于缩放后的PageRank值）。我可以在一个查询中做到吗？

下面的查询计算标定分数并返回总体前100个结果，而不是每年的前100个结果：

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 100
WITH year, COLLECT({title: title, page_rank: page_rank}) AS data, AVG(page_rank) AS avg_page_rank, stDev(page_rank) as stdDev
UNWIND data AS d
RETURN year, d.title AS title, ABS(d.page_rank-avg_page_rank)/stdDev AS scaled_score;

任何建议将不胜感激！

Answer 1

尝试一下：

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
WITH year, COLLECT({title: title, page_rank: page_rank})[..100] AS data, AVG(page_rank) AS avg_page_rank, stDev(page_rank) as stdDev
UNWIND data AS d
RETURN year, d.title AS title, ABS(d.page_rank-avg_page_rank)/stdDev AS scaled_score;

此查询会删除LIMIT子句，而是每年保留前100个（排序的）data项目。

Neo4j如何返回每个属性值的顶部节点

1 个答案: