The view that the returns to educational investments are highest for early childhood interventions is widely held and stems primarily from several influential randomized trials-Abecedarian, Perry, and the Early Training Project-that point to super-normal returns to early interventions. This paper presents a de novo analysis of these experiments, focusing on two core issues that have received limited attention in previous analyses: treatment effect heterogeneity by gender and over-rejection of the null hypothesis due to multiple inference. To address the latter issue, I implement a statistical framework that combines summary index tests with Familywise Error Rate and False Discovery Rate corrections. The first technique reduces the number of tests conducted; the latter two adjust the p-values for multiple inference. The primary finding of the reanalysis is that girls garnered substantial short-and long-term benefits from the interventions. However, there were no significant long-term benefits for boys. These conclusions, which have appeared ambiguous when using "naive" estimators that fail to adjust for multiple testing, contribute to a growing literature on the emerging female-male academic achievement gap. They also demonstrate that in complex studies where multiple questions are asked of the same data set, it can be important to declare the family of tests under consideration and to either consolidate measures or report adjusted as well as unadjusted p-values.

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Atmospheric rivers (ARs) play vital roles in the western United States and related regions globally, not only producing heavy precipitation and flooding, but also providing beneficial water supply. This paper introduces a scale for the intensity and impacts of ARs. Its utility may be greatest where ARs are the most impactful storm type and hurricanes, nor’easters, and tornadoes are nearly nonexistent. Two parameters dominate the hydrologic outcomes and impacts of ARs: vertically integrated water vapor transport (IVT) and AR duration [i.e., the duration of at least minimal AR conditions (IVT ≥ 250 kg m–1 s–1)]. The scale uses an observed or predicted time series of IVT at a given geographic location and is based on the maximum IVT and AR duration at that point during an AR event. AR categories 1–5 are defined by thresholds for maximum IVT (3-h average) of 250, 500, 750, 1,000, and 1,250 kg m–1 s–1, and by IVT exceeding 250 kg m–1 s–1 continuously for 24–48 h. If the AR event duration is less than 24 h, it is downgraded by one category. If it is longer than 48 h, it is upgraded one category. The scale recognizes that weak ARs are often mostly beneficial because they can enhance water supply and snowpack, while stronger ARs can become mostly hazardous, for example, if they strike an area with antecedent conditions that enhance vulnerability, such as burn scars or wet conditions. Extended durations can enhance impacts. Short durations can mitigate impacts.

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