elasticsearch boost problem

es_boost_problem.sh

curl -XDELETE 'http://localhost:9200/myindex'

curl -XPOST 'http://localhost:9200/myindex'

curl -XPOST 'http://localhost:9200/_refresh'

curl -XPUT 'http://localhost:9200/myindex/author/_mapping' -d '{
  "author": {
    "_boost": {
      "name": "boostFactor",
      "null_value": 1.0
    },
    "properties": {
      "id": {
        "type": "long"
      },
      "boostFactor": {
        "type": "float",
        "null_value": 1.0
      },
      "name": {
        "type": "string",
        "index": "not_analyzed",
        "boost": 20.0
      },
      "countryOfBirth": {
        "type": "string"
      }
    }
  }
}'

curl -XPUT 'http://localhost:9200/myindex/author/1' -d '{
  "id": 1,
  "boostFactor": 0.22,
  "name": "Sewald Kruse",
  "countryOfBirth": "Deutschland"
}'

curl -XPUT 'http://localhost:9200/myindex/author/2' -d '{
  "id": 2,
  "boostFactor": 0.61,
  "name": "Sergio Herold",
  "countryOfBirth": "Peru"
}'

curl -XPUT 'http://localhost:9200/myindex/author/3' -d '{
  "id": 3,
  "boostFactor": 0.03,
  "name": "Sebastion Wund",
  "countryOfBirth": "Deutschland"
}'

curl -XPUT 'http://localhost:9200/myindex/author/4' -d '{
  "id": 4,
  "boostFactor": 0.07,
  "name": "Gudrun Weil",
  "countryOfBirth": "Serbien"
}'

curl -XPOST 'http://localhost:9200/_refresh'

curl -XGET 'http://localhost:9200/myindex/author/_search' -d '{
  "query": {
    "prefix": {
      "name": "Se"
    }
  }
}'