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This article examines the treatment of statistics and error analysis in introductory physics lab manuals. It compares lab manuals from community colleges and universities and identifies inconsistencies in how these topics are addressed. The article suggests that a probabilistic approach to data analysis could enhance the teaching of measurement and uncertainty in the lab. It also highlights the International Organization for Standardization's guide to uncertainty in measurement as a valuable resource for standardizing lab instruction. The article concludes that there is a need for more consistent and rigorous treatment of statistics and error in introductory physics lab manuals. [Extracted from the article]

When biological populations expand into new territory, the evolutionary outcomes can be strongly influenced by genetic drift, the random fluctuations in allele frequencies. Meanwhile, spatial variability in the environment can also significantly influence the competition between subpopulations vying for space. Little is known about the interplay of these intrinsic and extrinsic sources of noise in population dynamics: When does environmental heterogeneity dominate over genetic drift or vice versa, and what distinguishes their population genetics signatures? Here, in the context of neutral evolution, we examine the interplay between a population's intrinsic, demographic noise and an extrinsic, quenched random noise provided by a heterogeneous environment. Using a multispecies Eden model, we simulate a population expanding over a landscape with random variations in local growth rates and measure how this variability affects genealogical tree structure, and thus genetic diversity. We find that, for strong heterogeneity, the genetic makeup of the expansion front is to a great extent predetermined by the set of fastest paths through the environment. The landscapedependent statistics of these optimal paths then supersede those of the population's intrinsic noise as the main determinant of evolutionary dynamics. Remarkably, the statistics for coalescence of genealogical lineages, derived from those deterministic paths, strongly resemble the statistics emerging from demographic noise alone in uniform landscapes. This cautions interpretations of coalescence statistics and raises new challenges for inferring past population dynamics. [ABSTRACT FROM AUTHOR]