Vocabulary metrics

Below are the detailed feedback metrics appearing in the response for vocabulary along with their descriptions, are as follows.

These metrics are returned by including include_ielts_feedback = 1 parameter in the Spontaneous Speech API.

Parameter	Description
vocab.overall_metrics.lexical_diversity	The degree of word diversity in the response.
vocab.overall_metrics.word_sophistication	The degree of use of advanced, less common vocabulary in the response.
vocab.overall_metrics.word_specificity	The degree of use of specific (less general) verbs, nouns, and adjectives which are specific to the meaning being conveyed.
vocab.overall_metrics.academic_language_use	The degree of use of academic language in the response.
vocab.overall_metrics.collocation_commonality	The degree of use of advanced word combinations.
vocab.overall_metrics.idiomaticity	The degree of use of idiomatic language.

Below is an example showing the snippet of vocabulary metrics:

"vocab": {
      "overall_metrics": {
        "lexical_diversity": {
          "score": 10,
          "level": "high"
        },
        "word_sophistication": {
          "score": 9,
          "level": "high"
        },
        "word_specificity": {
          "score": 6,
          "level": "mid",
          "message": "Your response uses more general words than most advanced speakers. To improve, you should aim to learn and use verbs, nouns, and adjectives more specific to the meaning you wish to convey."
        },
        "academic_language_use": {
          "score": 1,
          "level": "low",
          "message": "Your response is low on use of academic words. You should learn and use some academic language in your responses to improve."
        },
        "collocation_commonality": {
          "score": 9,
          "level": "high"
        },
        "idiomaticity": {
          "score": 4,
          "level": "mid"
        }
      }
    }