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Information About the Measures Included in the Study
| Variable | Unit | Year Measure Was Available | Source | Statistical Role |
|---|---|---|---|---|
| Positive Peace Index | 1–5 | 2019 | link | Predictor |
| Global Peace Index | 1–5 | 2019 | link | Predictor |
| Population Estimate | Millions | 2020 | link | Covariate |
| Gross Domestic Product | Millions | 2018 | link | Covariate |
| Population Density | People/km2 | 2018 | link | Covariate |
| Air travel | Thousands | 2014–2018 | link | Covariate |
| COVID‐19 statistics | N, N/1 mil. | 2020 | link | Outcome |
