{
  "processing_date": "2025-07-03T23:21:43.275322",
  "processed_years": [
    2015,
    2018,
    2022
  ],
  "file_formats": {
    "2015": "sav",
    "2018": "sav",
    "2022": "sav"
  },
  "key_variables": {
    "student_id": [
      "CNTSTUID",
      "STIDSTD",
      "STUID",
      "STDID",
      "StIDStd"
    ],
    "country": [
      "CNT",
      "CNTRYID",
      "COUNTRY"
    ],
    "school_id": [
      "CNTSCHID",
      "SCHOOLID",
      "SCHID",
      "SCID"
    ],
    "gender": [
      "ST004D01T",
      "ST04Q01",
      "ST003D01T"
    ],
    "age": [
      "AGE",
      "ST003Q02TA",
      "ST003D02T"
    ],
    "grade": [
      "ST001D01T",
      "ST01Q01"
    ],
    "escs": [
      "ESCS"
    ],
    "wealth": [
      "WEALTH"
    ],
    "cultural": [
      "CULTPOSS"
    ],
    "homework_time": [
      "TMINS",
      "ST057Q01TA",
      "ST57Q01",
      "ST046Q01TA"
    ],
    "motivation": [
      "MOTIVAT",
      "MOTIVA"
    ],
    "belong": [
      "BELONG"
    ],
    "perseverance": [
      "PERSEV",
      "GRIT"
    ],
    "math_score": [
      "PV1MATH",
      "PV2MATH",
      "PV3MATH",
      "PV4MATH",
      "PV5MATH"
    ],
    "read_score": [
      "PV1READ",
      "PV2READ",
      "PV3READ",
      "PV4READ",
      "PV5READ"
    ],
    "science_score": [
      "PV1SCIE",
      "PV2SCIE",
      "PV3SCIE",
      "PV4SCIE",
      "PV5SCIE"
    ]
  },
  "output_files": {
    "combined_international": "trend_analysis/pisa_combined_2006_2022.parquet",
    "spain_trends": "spain_trends/spain_trends_2006_2022.parquet",
    "spain_summary": "spain_trends/spain_summary_by_year.csv"
  },
  "notes": {
    "harmonization": "Variables harmonized across years using key_variables mapping",
    "spain_filtering": "Spain identified using country codes: ESP, ES, 724",
    "missing_data": "Missing values preserved as null/NaN in Parquet format",
    "optimization": "Uses column selection and Polars for efficient processing"
  }
}