地質学的データにおける周期性に関する非パラメトリック試験における実質的なバイアス
Science (New York, N.Y.)
|November 13, 1987
まとめ
周期的な絶滅率を示唆するために以前使用された統計的テストには欠陥があります. この方法はバイアスで,データ記録の問題により,人工的な2600万年周期を生成することがあります.
科学分野:
- パレオントロジー・パレオントロジー
- 統計分析 統計分析について
- 地球科学 地球科学 地球科学
背景:
- 過去の研究では,2600万年周期の周期的な大量絶滅が示唆されていた.
- 絶滅率の周期性を分析するために,非パラメトリック的統計テストが採用されています.
研究 の 目的:
- 周期的な絶滅率を検出するために使用される非パラメトリックテストを批判的に評価する.
- 絶滅率の周期性分析における潜在的なバイアスと人工的結果を調査する.
主な方法:
- 周期性に関する特定の非パラメトリック統計テストの分析.
- シミュレーションと測定誤差,特にシニョーロ・リップス効果に対するテストの感度検査.
- 統計的結果に対する時間間隔の不均等なデータの影響の評価.
主要な成果:
- 非パラメトリックテストは,実際のデータに関係なく,2600万年の期間の結論に大きく偏っている.
- このテストは,化石記録データにおける一般的な問題であるシニョール・リップス効果に対して非常に敏感です.
- 不均等なタイムシリーズのデータは,統計的に有意な,しかし人工的な2600万年の期間を生成することができます.
結論:
- 以前報告された2600万年の絶滅周期は,使用された統計的方法の人工物である可能性が高い.
- 採用されたテストは,絶滅率の真の周期性を検出するのに信頼できない.
- さらなる研究は,絶滅パターンを分析するためのより堅実な統計的アプローチを必要とします.
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