世界の人口の倍増はありえない
W Lutz1, W Sanderson, S Scherbov
1International Institute for Applied Systems Analysis, Laxenburg, Austria. lutz@iiasa.ac.at
Nature
|June 19, 1997
まとめ
この研究は,生育率,死亡率,移住傾向に関する専門家の洞察を活用して,世界的な人口予測のための新しい確率的アプローチを導入しています. 研究結果は,世界の人口が今世紀中に倍増しない確率は3分の2であることを示唆しています.
科学分野:
- デモグラフィー デモグラフィー 人口統計
- 人口研究 人口研究
- 統計モデリング 統計モデリング
背景:
- 伝統的な人口予測には,しばしば明確な不確実性定量化が欠けている.
- 既存の確率論的方法は,特定の国のタイムシリーズ分析に限られている.
- グローバルの人口統計データの制限と移行の複雑さは,タイムシリーズアプローチを妨げています.
研究 の 目的:
- 世界の人口予測のための新しい確率論的方法を開発する.
- 生育率,死亡率,移住の不確実性に関する専門家の意見を組み込む.
- 2100年までの人口の規模と年齢構造に関する確率予測を提供する.
主な方法:
- 生育率,死亡率,移住傾向に関する専門家の誘導を利用した.
- 重要な人口統計的変数に対する90%の不確実性範囲を組み込みました.
- 確率分布を生成するシミュレーション技術を採用した.
- 人口予測のための世界の13の地域を分析した.
主要な成果:
- 世界13地域における概率的な人口規模と年齢構造の分布を生成した.
- 2100年までに世界の人口が倍増しない確率は3分の2と推定されている.
- 世界規模での将来の人口動態動向に関する定量化された不確実性.
結論:
- 新規の確率論的アプローチは,地球の人口予測のためのより堅牢な方法を提供します.
- 専門家の意見は,データが乏しい地域では,人口予測の不確実性に対処するために極めて重要です.
- 将来の世界人口増加は,以前から考えられていたよりも遅い成長の可能性があり,大きな不確実性がある.
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