`Worst case' methodology for the initial assessment of societal risk from proposed major accident installations

This is an up-to-date introduction to and overview of the Minimum Description Length (MDL) Principle, a theory of inductive inference that can be applied to general problems in statistics, machine learning and pattern recognition. While MDL was originally based on data compression ideas, this introduction can be read without any knowledge thereof. It takes into account all major developments since 2007, the last time an extensive overview was written. These include new methods for model selection and averaging and hypothesis testing, as well as the first completely general definition of MDL estimators. Incorporating these developments, MDL can be seen as a powerful extension of both penalized likelihood and Bayesian approaches, in which penalization functions and prior distributions are replaced by more general luckiness functions, average-case methodology is replaced by a more robust worst-case approach, and in which methods classically viewed as highly distinct, such as AIC versus BIC and cross-validation versus Bayes can, to a large extent, be viewed from a unified perspective.

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Mosaic Mapping: A Means of Tiling Images to Shorten Acquisition Speed for Lower - Magnification SEM Images and Wavelength Dispersive Spectrometers (WDS) X-Ray Maps

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100164659 ◽

1996 ◽

Vol 54 ◽

pp. 438-439

Author(s):

J.D. Geller ◽

C.R. Herrington

Keyword(s):

Limiting Factors ◽

X Rays ◽

Angular Range ◽

Acceptance Angle ◽

Sem Images ◽

Worst Case ◽

X Ray ◽

Focusing Distance ◽

Layered Crystals ◽

Working Distance

The minimum magnification for which an image can be acquired is determined by the design and implementation of the electron optical column and the scanning and display electronics. It is also a function of the working distance and, possibly, the accelerating voltage. For secondary and backscattered electron images there are usually no other limiting factors. However, for x-ray maps there are further considerations. The energy-dispersive x-ray spectrometers (EDS) have a much larger solid angle of detection that for WDS. They also do not suffer from Bragg’s Law focusing effects which limit the angular range and focusing distance from the diffracting crystal. In practical terms EDS maps can be acquired at the lowest magnification of the SEM, assuming the collimator does not cutoff the x-ray signal. For WDS the focusing properties of the crystal limits the angular range of acceptance of the incident x-radiation. The range is dependent upon the 2d spacing of the crystal, with the acceptance angle increasing with 2d spacing. The natural line width of the x-ray also plays a role. For the metal layered crystals used to diffract soft x-rays, such as Be - O, the minimum magnification is approximately 100X. In the worst case, for the LEF crystal which diffracts Ti - Zn, ˜1000X is the minimum.

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Reassessment of Suicide Attempters at Home, Shortly After Discharge from Hospital

Crisis ◽

10.1027/0227-5910/a000041 ◽

2010 ◽

Vol 31 (6) ◽

pp. 303-310 ◽

Cited By ~ 9

Author(s):

Bas Verwey ◽

Jeroen A. van Waarde ◽

Molla A. Bozdağ ◽

Iris van Rooij ◽

Edwin de Beurs ◽

...

Keyword(s):

Suicide Attempt ◽

General Hospital ◽

Hospital Environment ◽

Initial Assessment ◽

Suicide Attempters ◽

Systematic Assessment ◽

Suicide Intent ◽

Initial Hospital ◽

Discharge From Hospital ◽

At Home

Background: Assessment of suicide attempters in a general hospital may be influenced by the condition of the patient and the unfavorable circumstances of the hospital environment. Aims: To determine whether the results of a reassessment at home shortly after discharge from hospital differ from the initial assessment in the hospital. Methods: In this prospective study, systematic assessment of 52 suicide attempters in a general hospital was compared with reassessment at home, shortly after discharge. Results: Reassessments at home concerning suicide intent, motives for suicide attempt, and dimensions of psychopathology did not differ significantly from the initial hospital assessment. However, patients’ motives for the suicide attempt had changed to being less impulsive and more suicidal, worrying was significantly higher, and self-esteem was significantly lower. A third of the patients had forgotten their aftercare arrangements and most patients who initially felt no need for additional help had changed their mind at reassessment. Conclusions: Results from this group of suicide attempters suggest that a brief reassessment at home shortly after discharge from hospital should be considered.

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Delay Discounting in Impulsive Behavior

European Psychologist ◽

10.1027/1016-9040/a000360 ◽

2019 ◽

Vol 24 (4) ◽

pp. 312-321 ◽

Cited By ~ 4

Author(s):

Diana Moreira ◽

Fernando Barbosa

Keyword(s):

Delay Discounting ◽

Human Subjects ◽

Empirical Studies ◽

Cochrane Collaboration ◽

Initial Assessment ◽

Impulsive Behavior ◽

Manual Search ◽

Study Results ◽

Depth Analysis ◽

The Future

Abstract. Delay discounting (DD) is the process of devaluing results that happen in the future. With this review, we intend to identify specificities in the processes of DD in impulsive behavior. Studies were retrieved from multiple literature databases, through rigorous criteria (we included systematic reviews and empirical studies with adult human subjects), following the procedures of the Cochrane Collaboration initiative. Of the 174 documents obtained, 19 were considered eligible for inclusion and were retained for in-depth analysis. In addition, 13 studies from the manual search were included. Thus, a total of 32 studies were selected for review. The objectives/hypotheses, results, and the main conclusion(s) were extracted from each study. Results show that people with pronounced traits of impulsivity discount rewards more markedly, that is, they prefer immediate rewards, though of less value, or postponed losses, even though they worsen in the future. Taken together, the existing data suggest the importance of inserting DD as a tool for initial assessment in conjunction with measures of addiction and stress level, as well as the consideration of new therapies.

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