"value over replacement player" meaning in English

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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "A statistical measure which evaluates the relative performance of a batter or pitcher compared to a hypothetical replacement player of average fielding skill and below average hitting or pitching."
      ],
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      "raw_glosses": [
        "(baseball) A statistical measure which evaluates the relative performance of a batter or pitcher compared to a hypothetical replacement player of average fielding skill and below average hitting or pitching."
      ],
      "topics": [
        "ball-games",
        "baseball",
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      "wikipedia": [
        "value over replacement player"
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  "word": "value over replacement player"
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      "expansion": "value over replacement player",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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        "English lemmas",
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      "glosses": [
        "A statistical measure which evaluates the relative performance of a batter or pitcher compared to a hypothetical replacement player of average fielding skill and below average hitting or pitching."
      ],
      "links": [
        [
          "baseball",
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        "(baseball) A statistical measure which evaluates the relative performance of a batter or pitcher compared to a hypothetical replacement player of average fielding skill and below average hitting or pitching."
      ],
      "topics": [
        "ball-games",
        "baseball",
        "games",
        "hobbies",
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        "value over replacement player"
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  "word": "value over replacement player"
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