Mathias Basner

Bio: Mathias Basner is an academic researcher from University of Pennsylvania. The author has contributed to research in topics: Noise & Sleep deprivation. The author has an hindex of 41, co-authored 183 publications receiving 8052 citations. Previous affiliations of Mathias Basner include Harvard University & German Aerospace Center.

Ultra-short objective alertness assessment: an adaptive duration version of the 3 minute PVT (PVT-BA) accurately tracks changes in psychomotor vigilance induced by sleep restriction

Abstract: Abstract Study Objectives The Psychomotor Vigilance Test (PVT) is a widely used and sensitive assay of the cognitive deficits associated with sleep loss and circadian misalignment. As even shorter versions of the PVT are often considered too long, I developed and validated an adaptive duration version of the 3 min PVT (PVT-BA). Methods The PVT-BA algorithm was trained on data from 31 subjects participating in a total sleep deprivation protocol and validated in 43 subjects undergoing 5 days of partial sleep restriction under controlled laboratory conditions. With each subject response, the algorithm updated the odds of the test being high, medium or low performance based on lapses plus false starts on the full 3 min PVT-B. Results With a decision threshold of 99.619%, PVT-BA classified 95.1% of training data tests correctly without incorrect classifications across two performance categories (i.e. high as low or low as high) and resulted in an average test duration of 1 min 43 s with a minimum duration of 16.4 s. Agreement corrected for chance between PVT-B and PVT-BA was “almost perfect” for both the training (kappa = 0.92) and validation data (kappa = 0.85). Across the three performance categories and data sets, sensitivity averaged 92.2% (range 74.9–100%) and specificity averaged 96.0% (range 88.3–99.2%). Conclusions PVT-BA is an accurate adaptive version of PVT-B and, to my knowledge, the shortest version to date that maintains key properties of the standard 10 min duration PVT. PVT-BA will facilitate the use of the PVT in settings in which it was previously considered impractical.

Effects of nocturnal air and rail traffic noise on sleep

Abstract: Undisturbed and sufficiently long sleep is a prerequisite for a healthy life as well as for the prevention of fatigue-induced accidents. Especially the increasing air and freight rail traffic is more and more shifted to shoulder and night-time hours due to missing capacity and infrastructure during daytime. Thus, the sleep of residents near airports or railway tracks is increasingly affected by traffic noise. Only very few main airports, such as Frankfurt (Germany), implemented a night flight ban in order to countervail this trend. Since 1999 the Institute of Aerospace Medicine of the German Aerospace Center (DLR) has investigated these night time noise effects in several field studies in which the sound pressure levels LAS and LAF and sound files were continuously measured with class one sound level meters at the sleeper’s ear. Sleep structure was recorded with polysomnography (simultaneous measurement of brain waves, eye movements, and muscle tone), the gold-standard to quantify sleep objectively. The results on sleep quality and additional awakening reactions due to traffic noise from former studies performed at Cologne/Bonn airport (high night time traffic) and a busy railway track in the Rhine valley (high night time freight traffic) are compared with the results of the recently completed NORAH (Noise-Related Annoyance, Cognition, and Health) study at Frankfurt airport. In the latter study data were collected both before as well as after the implementation of a ban of night flights between 11 p.m. and 5 a.m.. Sound exposure distributions, average sound levels and sound level rise time distributions at the sleepers’ ear are presented for all three studies.

Multiple Imputation for Nonresponse in Surveys

Abstract: 25. Multiple Imputation for Nonresponse in Surveys. By D. B. Rubin. ISBN 0 471 08705 X. Wiley, Chichester, 1987. 258 pp. £30.25.

Of Theory and Practice

Abstract: Much has been written about theory and practice in the law, and the tension between practitioners and theorists. Judges do not cite theoretical articles often; they rarely "apply" theories to particular cases. These arguments are not revisited. Instead the Essay explores the working and interaction of theory and practice, practitioners and theorists. The Essay starts with a story about solving a legal issue using our intellectual tools - theory, practice, and their progenies: experience and "gut." Next the Essay elaborates on the nature of theory, practice, experience and "gut." The third part of the Essay discusses theories that are helpful to practitioners and those that are less helpful. The Essay concludes that practitioners theorize, and theorists practice. They use these intellectual tools differently because the goals and orientations of theorists and practitioners, and the constraints under which they act, differ. Theory, practice, experience and "gut" help us think, remember, decide and create. They complement each other like the two sides of the same coin: distinct but inseparable.

Reliability and validity

Abstract: Definition: To what extent does the study allow us to draw conclusions about a causal effect between two or more constructs? Issues: Selection, maturation, history, mortality, testing, regression towrd the mean, selection by maturation, treatment by mortality, treatment by testing, measured treatment variables Increase: Eliminate the threats, above all do experimental manipulations, random assignment, and counterbalancing.