Improved confidence intervals for estimating the position of a mass extinction boundary

From: Paleobiology | Date: January 1, 2004| Author: Marshall, Charles R; Wang, Steve C | Copyright information

Abstract.-Marshall (1995) used the distribution of the endpoints of 50% range extensions added to the stratigraphic ranges of individual taxa to bracket the position of an extinction boundary. Here we describe two improvements to Marshall's method. First, we show that more precise estimates of the position of such a boundary may be obtained using range extensions with confidence levels of less than 50% (e.g., 20%). Second, we introduce a new method of calculating confidence intervals that exp...

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