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作者：Akritas, Michael G.; Antoniou, Efi S.; Kuha, Jouni
作者单位：Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; University of London; London School Economics & Political Science; University of London; London School Economics & Political Science
摘要：We propose a nonparametric approach to the analysis of factorial designs where each subject is observed at two time points and both observations are subject to missingness. The procedures are fully nonparametric in that they do not require continuity, and do not impose models to describe the relation of the response distribution in different factor-level combinations. The approach for estimating and testing treatment and time effects is based on a method, which we introduce, for estimating a d...
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作者：Morris, Jeffrey S.; Arroyo, Cassandra; Coull, Brent A.; Ryan, Louise M.; Herrick, Richard; Gortmaker, Steven L.
作者单位：University of Texas System; UTMD Anderson Cancer Center; Morehouse School of Medicine; Harvard University; Harvard T.H. Chan School of Public Health; Harvard University; Harvard T.H. Chan School of Public Health
摘要：We present a case study illustrating the challenges of analyzing accelerometer data taken from a sample of children participating in an intervention study designed to increase physical activity. An accelerometer is a small device worn on the hip that records the minute-by-minute activity levels throughout the day for each day it is worn. The resulting data are irregular functions characterized by many peaks representing short bursts of intense activity. We model these data using the wavelet-ba...
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作者：Tan, Zhiqiang
作者单位：Johns Hopkins University; Johns Hopkins Bloomberg School of Public Health
摘要：Recent researches in econometrics and statistics have gained considerable insights into the use of instrumental variables (lVs) for causal inference. A basic idea is that IVs serve as an experimental handle, the turning of which may change each individual's treatment status and, through and only through this effect, also change observed outcome. The average difference in observed outcome relative to that in treatment status gives the average treatment effect for those whose treatment status is...
