56,181 research outputs found
Applied statistics: A review
The main phases of applied statistical work are discussed in general terms.
The account starts with the clarification of objectives and proceeds through
study design, measurement and analysis to interpretation. An attempt is made to
extract some general notions.Comment: Published at http://dx.doi.org/10.1214/07-AOAS113 in the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Concepts and a case study for a flexible class of graphical Markov models
With graphical Markov models, one can investigate complex dependences,
summarize some results of statistical analyses with graphs and use these graphs
to understand implications of well-fitting models. The models have a rich
history and form an area that has been intensively studied and developed in
recent years. We give a brief review of the main concepts and describe in more
detail a flexible subclass of models, called traceable regressions. These are
sequences of joint response regressions for which regression graphs permit one
to trace and thereby understand pathways of dependence. We use these methods to
reanalyze and interpret data from a prospective study of child development, now
known as the Mannheim Study of Children at Risk. The two related primary
features concern cognitive and motor development, at the age of 4.5 and 8 years
of a child. Deficits in these features form a sequence of joint responses.
Several possible risks are assessed at birth of the child and when the child
reached age 3 months and 2 years.Comment: 21 pages, 7 figures, 7 tables; invited, refereed chapter in a boo
Frequentist statistics as a theory of inductive inference
After some general remarks about the interrelation between philosophical and
statistical thinking, the discussion centres largely on significance tests.
These are defined as the calculation of -values rather than as formal
procedures for ``acceptance'' and ``rejection.'' A number of types of null
hypothesis are described and a principle for evidential interpretation set out
governing the implications of -values in the specific circumstances of each
application, as contrasted with a long-run interpretation. A variety of more
complicated situations are discussed in which modification of the simple
-value may be essential.Comment: Published at http://dx.doi.org/10.1214/074921706000000400 in the IMS
Lecture Notes--Monograph Series
(http://www.imstat.org/publications/lecnotes.htm) by the Institute of
Mathematical Statistics (http://www.imstat.org
Another self-similar blast wave: Early time asymptote with shock heated electrons and high thermal conductivity
Accurate approximations are presented for the self-similar structures of nonradiating blast waves with adiabatic ions, isothermal electrons, and equation ion and electron temperatures at the shock. The cases considered evolve in cavities with power law ambient densities (including the uniform density case) and have negligible external pressure. The results provide the early time asymptote for systems with shock heating of electrons and strong thermal conduction. In addition, they provide analytical results against which two fluid numerical hydrodynamic codes can be checked
Revealing local failed supernovae with neutrino telescopes
We study the detectability of neutrino bursts from nearby direct black
hole-forming collapses (failed supernovae) at Megaton detectors. Due to their
high energetics, these bursts could be identified - by the time coincidence of
N >= 2 or N >= 3 events within a ~ 1 s time window - from as far as ~ 4-5 Mpc
away. This distance encloses several supernova-rich galaxies, so that failed
supernova bursts could be detected at a rate of up to one per decade,
comparable to the expected rate of the more common, but less energetic, neutron
star-forming collapses. Thus, the detection of a failed supernova within the
lifetime of a Mt detector is realistic. It might give the first evidence of
direct black hole formation, with important implications on the physics of this
phenomenon.Comment: LaTeX, 4 pages, 4 figures; minor changes to the text, results
unchange
Saturn S-IB stage Final static test report, stage S-IB-4
Acceptance static test firing data for Saturn flight stage S-IB-
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