我有一些具有相同内容的文档，但是当我尝试查询这些文档时，尽管查询的字段包含相同的文本，但我得到了不同的分数。我已经解释了分数，但我无法分析和找到分数不同的原因。
我的查询是
curl 'localhost:9200/acqindex/_search?pretty=1' -d '{
"explain" : true,
"query" : {
"query_string" : {
"query" : "text:shimla"
}
}
}'
搜索回复：
{
"took" : 8,
"timed_out" : false,
"_shards" : {
"total" : 5,
"successful" : 5,
"failed" : 0
},
"hits" : {
"total" : 31208,
"max_score" : 268.85962,
"hits" : [ {
"_shard" : 0,
"_node" : "KOebAnGhSJKUHLPNxndcpQ",
"_index" : "acqindex",
"_type" : "autocomplete_questions",
"_id" : "50efec6c38cc6fdabd8653a3",
"_score" : 268.85962, "_source" : {"_class":"com.ixigo.next.cms.model.AutoCompleteObject","_id":"50efec6c38cc6fdabd8653a3","ad":"rajasthan,IN","category":["Destination"],"ctype":"destination","eid":"503b2a65e4b032e338f0d24b","po":8.772307692307692,"text":"shimla","url":"/travel-guide/shimla"},
"_explanation" : {
"value" : 268.85962,
"description" : "sum of:",
"details" : [ {
"value" : 38.438133,
"description" : "weight(text:shi in 5860), product of:",
"details" : [ {
"value" : 0.37811017,
"description" : "queryWeight(text:shi), product of:",
"details" : [ {
"value" : 5.0829277,
"description" : "idf(docFreq=7503, maxDocs=445129)"
}, {
"value" : 0.074388266,
"description" : "queryNorm"
} ]
}, {
"value" : 101.658554,
"description" : "fieldWeight(text:shi in 5860), product of:",
"details" : [ {
"value" : 1.0,
"description" : "tf(termFreq(text:shi)=1)"
}, {
"value" : 5.0829277,
"description" : "idf(docFreq=7503, maxDocs=445129)"
}, {
"value" : 20.0,
"description" : "fieldNorm(field=text, doc=5860)"
} ]
} ]
}, {
"value" : 66.8446,
"description" : "weight(text:shim in 5860), product of:",
"details" : [ {
"value" : 0.49862078,
"description" : "queryWeight(text:shim), product of:",
"details" : [ {
"value" : 6.7029495,
"description" : "idf(docFreq=1484, maxDocs=445129)"
}, {
"value" : 0.074388266,
"description" : "queryNorm"
} ]
}, {
"value" : 134.05899,
"description" : "fieldWeight(text:shim in 5860), product of:",
"details" : [ {
"value" : 1.0,
"description" : "tf(termFreq(text:shim)=1)"
}, {
"value" : 6.7029495,
"description" : "idf(docFreq=1484, maxDocs=445129)"
}, {
"value" : 20.0,
"description" : "fieldNorm(field=text, doc=5860)"
} ]
} ]
}, {
"value" : 81.75818,
"description" : "weight(text:shiml in 5860), product of:",
"details" : [ {
"value" : 0.5514458,
"description" : "queryWeight(text:shiml), product of:",
"details" : [ {
"value" : 7.413075,
"description" : "idf(docFreq=729, maxDocs=445129)"
}, {
"value" : 0.074388266,
"description" : "queryNorm"
} ]
}, {
"value" : 148.2615,
"description" : "fieldWeight(text:shiml in 5860), product of:",
"details" : [ {
"value" : 1.0,
"description" : "tf(termFreq(text:shiml)=1)"
}, {
"value" : 7.413075,
"description" : "idf(docFreq=729, maxDocs=445129)"
}, {
"value" : 20.0,
"description" : "fieldNorm(field=text, doc=5860)"
} ]
} ]
}, {
"value" : 81.8187,
"description" : "weight(text:shimla in 5860), product of:",
"details" : [ {
"value" : 0.55164987,
"description" : "queryWeight(text:shimla), product of:",
"details" : [ {
"value" : 7.415818,
"description" : "idf(docFreq=727, maxDocs=445129)"
}, {
"value" : 0.074388266,
"description" : "queryNorm"
} ]
}, {
"value" : 148.31636,
"description" : "fieldWeight(text:shimla in 5860), product of:",
"details" : [ {
"value" : 1.0,
"description" : "tf(termFreq(text:shimla)=1)"
}, {
"value" : 7.415818,
"description" : "idf(docFreq=727, maxDocs=445129)"
}, {
"value" : 20.0,
"description" : "fieldNorm(field=text, doc=5860)"
} ]
} ]
} ]
}
}, {
"_shard" : 1,
"_node" : "KOebAnGhSJKUHLPNxndcpQ",
"_index" : "acqindex",
"_type" : "autocomplete_questions",
"_id" : "50efed1c38cc6fdabd8b8d2f",
"_score" : 268.29953, "_source" : {"_id":"50efed1c38cc6fdabd8b8d2f","ad":"himachal pradesh,IN","category":["Hill","See and Do","Destination","Mountain","Nature and Wildlife"],"ctype":"destination","eid":"503b2a64e4b032e338f0d0af","po":8.781970310391364,"text":"shimla","url":"/travel-guide/shimla"},
"_explanation" : {
"value" : 268.29953,
"description" : "sum of:",
"details" : [ {
"value" : 38.52957,
"description" : "weight(text:shi in 14769), product of:",
"details" : [ {
"value" : 0.37895453,
"description" : "queryWeight(text:shi), product of:",
"details" : [ {
"value" : 5.083667,
"description" : "idf(docFreq=7263, maxDocs=431211)"
}, {
"value" : 0.07454354,
"description" : "queryNorm"
} ]
}, {
"value" : 101.67334,
"description" : "fieldWeight(text:shi in 14769), product of:",
"details" : [ {
"value" : 1.0,
"description" : "tf(termFreq(text:shi)=1)"
}, {
"value" : 5.083667,
"description" : "idf(docFreq=7263, maxDocs=431211)"
}, {
"value" : 20.0,
"description" : "fieldNorm(field=text, doc=14769)"
} ]
} ]
}, {
"value" : 66.67524,
"description" : "weight(text:shim in 14769), product of:",
"details" : [ {
"value" : 0.49850821,
"description" : "queryWeight(text:shim), product of:",
"details" : [ {
"value" : 6.6874766,
"description" : "idf(docFreq=1460, maxDocs=431211)"
}, {
"value" : 0.07454354,
"description" : "queryNorm"
} ]
}, {
"value" : 133.74953,
"description" : "fieldWeight(text:shim in 14769), product of:",
"details" : [ {
"value" : 1.0,
"description" : "tf(termFreq(text:shim)=1)"
}, {
"value" : 6.6874766,
"description" : "idf(docFreq=1460, maxDocs=431211)"
}, {
"value" : 20.0,
"description" : "fieldNorm(field=text, doc=14769)"
} ]
} ]
}, {
"value" : 81.53204,
"description" : "weight(text:shiml in 14769), product of:",
"details" : [ {
"value" : 0.5512571,
"description" : "queryWeight(text:shiml), product of:",
"details" : [ {
"value" : 7.3951015,
"description" : "idf(docFreq=719, maxDocs=431211)"
}, {
"value" : 0.07454354,
"description" : "queryNorm"
} ]
}, {
"value" : 147.90204,
"description" : "fieldWeight(text:shiml in 14769), product of:",
"details" : [ {
"value" : 1.0,
"description" : "tf(termFreq(text:shiml)=1)"
}, {
"value" : 7.3951015,
"description" : "idf(docFreq=719, maxDocs=431211)"
}, {
"value" : 20.0,
"description" : "fieldNorm(field=text, doc=14769)"
} ]
} ]
}, {
"value" : 81.56268,
"description" : "weight(text:shimla in 14769), product of:",
"details" : [ {
"value" : 0.55136067,
"description" : "queryWeight(text:shimla), product of:",
"details" : [ {
"value" : 7.3964915,
"description" : "idf(docFreq=718, maxDocs=431211)"
}, {
"value" : 0.07454354,
"description" : "queryNorm"
} ]
}, {
"value" : 147.92982,
"description" : "fieldWeight(text:shimla in 14769), product of:",
"details" : [ {
"value" : 1.0,
"description" : "tf(termFreq(text:shimla)=1)"
}, {
"value" : 7.3964915,
"description" : "idf(docFreq=718, maxDocs=431211)"
}, {
"value" : 20.0,
"description" : "fieldNorm(field=text, doc=14769)"
} ]
} ]
} ]
}
}
}
}
文件是：
{“_class”：“com.ixigo.next.cms.model.AutoCompleteObject”，“_id”：“50efec6c38cc6fdabd8653a3”，“ad”：“拉贾斯坦邦，IN”，“类别”：[“目的地”]，“ctype ":"目的地","eid":"503b2a65e4b032e338f0d24b","po":8.772307692307692,"text":"西姆拉","url":"/旅行指南/西姆拉"}
{"_id":"50efed1c38cc6fdabd8b8d2f","ad":"喜马偕尔 邦，IN","类别":["山","参见和 做","目的地","山","自然和野生动物"],"ctype":"目的地","eid":"503b2a64e4b032e338f0d0af","po":8.781970310391364,"text":"shimla", "url":"/旅行指南/西姆拉"}
请指导我理解分数差异的原因。
lucene 分数取决于不同的因素。使用tf idf相似度（默认）主要取决于：
在您的情况下，您必须考虑到您的两个文档来自不同的分片，因此每个分片的分数都是单独计算的，因为每个分片实际上都是一个单独的 lucene 索引。
您可能想看看 Elasticsearch 提供的更昂贵的 DFS、“查询然后获取”搜索类型，以实现更准确的评分。默认是简单的查询然后获取。
javanna明确指出了分数差异来自于多个分片评分的问题。这些分片可能有不同数量的文档。这会影响评分算法。
但是，Elasticsearch：权威指南 的作者告知：
添加到索引中的文档越多，本地和全局 IDF [逆文档频率] 之间的差异就会减小。凭借现实世界中的大量数据，当地的 IDF 很快就趋于平衡。问题不在于相关性被破坏，而在于数据太少。
您不应该在生产中使用 dfs_query_then_fetch。为了进行测试，请将索引放在一个主分片上或指定
?search_type=dfs_query_then_fetch在您的情况下，您必须考虑到您的两个文档来自不同的分片，因此每个分片的分数都是单独计算的，因为每个分片实际上都是一个单独的 lucene 索引。2013 年 1 月 29 日