# Field boost changes in ElasticSearch version7.6.2

**URL:** <https://discuss.elastic.co/t/field-boost-changes-in-elasticsearch-version7-6-2/247882>\
**Category:** Elasticsearch\
**Created:** [September 8, 2020, 11:39am UTC](https://discuss.elastic.co/t/field-boost-changes-in-elasticsearch-version7-6-2/247882 "2020-09-08T11:39:49Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![Barkha\_Jain](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/barkha_jain/32/45778_2.png) [@Barkha\_Jain](https://discuss.elastic.co/u/Barkha_Jain)\
**Post date:** [September 8, 2020, 11:39am UTC](https://discuss.elastic.co/t/field-boost-changes-in-elasticsearch-version7-6-2/247882/1 "2020-09-08T11:39:49Z")

</div>

We recently moved to ElasticSearch version 7.6.2 from version 6.2.3  
The search query that we use has field boosts applied in different match queries. I was looking into the changes related to scoring of docs in the new version and found that the boost applied in the newer version varies from the actual number that I used in the search query.  
(I checked using the explain API).  
eg.,  
Search Query:

```auto
{
  "explain": true, 
  "query": {
    "match": {
      "connectorSpecific.alpha": {
        "query":"goexpense",
      "boost": 5
      }
    }
  }
}

```

Score Generated:

```auto

        "_explanation" : {
          "value" : 46.694355,
          "description" : "weight(connectorSpecific.alpha:goexpense in 226) [PerFieldSimilarity], result of:",
          "details" : [
            {
              "value" : 46.694355,
              "description" : "score(freq=1.0), computed as boost * idf * tf from:",
              "details" : [
                {
                  "value" : 11.0,
                  "description" : "boost",
                  "details" : []
                },
                {
                  "value" : 6.449522,
                  "description" : "idf, computed as log(1 + (N - n + 0.5) / (n + 0.5)) from:",
                  "details" : [
                    {
                      "value" : 2,
                      "description" : "n, number of documents containing term",
                      "details" : []
                    },
                    {
                      "value" : 1580,
                      "description" : "N, total number of documents with field",
                      "details" : []
                    }
                  ]
                },
                {
                  "value" : 0.6581793,
                  "description" : "tf, computed as freq / (freq + k1 * (1 - b + b * dl / avgdl)) from:",
                  "details" : [
                    {
                      "value" : 1.0,
                      "description" : "freq, occurrences of term within document",
                      "details" : []
                    },
                    {
                      "value" : 1.2,
                      "description" : "k1, term saturation parameter",
                      "details" : []
                    },
                    {
                      "value" : 0.75,
                      "description" : "b, length normalization parameter",
                      "details" : []
                    },
                    {
                      "value" : 1.0,
                      "description" : "dl, length of field",
                      "details" : []
                    },
                    {
                      "value" : 4.1031647,
                      "description" : "avgdl, average length of field",
                      "details" : []
                    }
                  ]
                }
              ]
            }
          ]
        }

```

Is there a reason for such a difference in boost?

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [October 6, 2020, 11:39am UTC](https://discuss.elastic.co/t/field-boost-changes-in-elasticsearch-version7-6-2/247882/2 "2020-10-06T11:39:58Z")

</div>

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