{
    "classifications": [
        {
            "column": "Name",
            "role": "attribute",
            "confidence": 0.6,
            "reason": "Player name, descriptive text with many distinct values; could serve as a grouping label but is primarily displayed"
        },
        {
            "column": "Date",
            "role": "dimension",
            "confidence": 0.95,
            "reason": "Match date, used for time slicing"
        },
        {
            "column": "Tournament",
            "role": "dimension",
            "confidence": 0.8,
            "reason": "Tournament label used to group or filter matches"
        },
        {
            "column": "Surface",
            "role": "dimension",
            "confidence": 0.98,
            "reason": "Low-cardinality categorical (Clay, Grass, Hard, Carpet)"
        },
        {
            "column": "Rd",
            "role": "dimension",
            "confidence": 0.97,
            "reason": "Round code, low-cardinality category"
        },
        {
            "column": "Rk",
            "role": "measure",
            "confidence": 0.55,
            "reason": "Player ranking, numeric and averageable, though it could be used as a dimension"
        },
        {
            "column": "vRk",
            "role": "measure",
            "confidence": 0.55,
            "reason": "Opponent ranking, numeric and averageable"
        },
        {
            "column": "against",
            "role": "attribute",
            "confidence": 0.85,
            "reason": "Messy free-form opponent text, nearly unique per row"
        },
        {
            "column": "Score",
            "role": "attribute",
            "confidence": 0.8,
            "reason": "Free-form match score string with high cardinality"
        },
        {
            "column": "TP",
            "role": "measure",
            "confidence": 0.85,
            "reason": "Total points won, a numeric count"
        },
        {
            "column": "Aces",
            "role": "measure",
            "confidence": 0.95,
            "reason": "Count of aces, aggregated"
        },
        {
            "column": "DFs",
            "role": "measure",
            "confidence": 0.95,
            "reason": "Count of double faults, aggregated"
        },
        {
            "column": "SP",
            "role": "measure",
            "confidence": 0.93,
            "reason": "Service points count"
        },
        {
            "column": "1SP",
            "role": "measure",
            "confidence": 0.93,
            "reason": "First-serve points won count"
        },
        {
            "column": "2SP",
            "role": "measure",
            "confidence": 0.93,
            "reason": "Second-serve points won count"
        },
        {
            "column": "vA",
            "role": "measure",
            "confidence": 0.92,
            "reason": "Opponent aces count"
        },
        {
            "column": "Time",
            "role": "measure",
            "confidence": 0.6,
            "reason": "Match duration as an h:mm string, averageable once converted; stored as text"
        }
    ]
}