```json { "classifications": [ { "column": "Overall rank", "role": "dimension", "confidence": 0.85, "reason": "Ordinal ranking used for sorting/filtering; not aggregated or used as a join key" }, { "column": "Country or region", "role": "identifier", "confidence": 0.95, "reason": "Primary key with 156 distinct values matching row count; uniquely identifies each country" }, { "column": "Score", "role": "measure", "confidence": 0.95, "reason": "Numeric happiness score to be aggregated (avg/sum) across countries or regions" }, { "column": "GDP per capita", "role": "measure", "confidence": 0.9, "reason": "Numeric economic indicator to be aggregated; continuous values suitable for avg/sum" }, { "column": "Social support", "role": "measure", "confidence": 0.9, "reason": "Numeric metric to be aggregated; continuous values representing social support levels" }, { "column": "Healthy life expectancy", "role": "measure", "confidence": 0.9, "reason": "Numeric health metric to be aggregated; continuous values suitable for statistical analysis" }, { "column": "Freedom to make life choices", "role": "measure", "confidence": 0.9, "reason": "Numeric freedom index to be aggregated; continuous values for statistical operations" }, { "column": "Generosity", "role": "measure", "confidence": 0.9, "reason": "Numeric generosity metric to be aggregated; continuous values for avg/sum calculations" }, { "column": "Perceptions of corruption", "role": "measure", "confidence": 0.9, "reason": "Numeric corruption perception index to be aggregated; continuous values for analysis" } ] } ```