66,478 research outputs found
Conflation of short identity-by-descent segments bias their inferred length distribution
Identity-by-descent (IBD) is a fundamental concept in genetics with many
applications. In a common definition, two haplotypes are said to contain an IBD
segment if they share a segment that is inherited from a recent shared common
ancestor without intervening recombination. Long IBD segments (> 1cM) can be
efficiently detected by a number of algorithms using high-density SNP array
data from a population sample. However, these approaches detect IBD based on
contiguous segments of identity-by-state, and such segments may exist due to
the conflation of smaller, nearby IBD segments. We quantified this effect using
coalescent simulations, finding that nearly 40% of inferred segments 1-2cM long
are results of conflations of two or more shorter segments, under demographic
scenarios typical for modern humans. This biases the inferred IBD segment
length distribution, and so can affect downstream inferences. We observed this
conflation effect universally across different IBD detection programs and human
demographic histories, and found inference of segments longer than 2cM to be
much more reliable (less than 5% conflation rate). As an example of how this
can negatively affect downstream analyses, we present and analyze a novel
estimator of the de novo mutation rate using IBD segments, and demonstrate that
the biased length distribution of the IBD segments due to conflation can lead
to inflated estimates if the conflation is not modeled. Understanding the
conflation effect in detail will make its correction in future methods more
tractable
A rational approach to the harmonisation of the thermal properties of building materials
The Energy Systems Research Unit at the University of Strathclyde in Glasgow was contracted by the Building Research Establishment to review existing data-sets of thermo-physical properties of building materials and devise vetting and conflation mechanisms. The UK Chartered Institute of Building Services Engineers subsequently commissioned a project to extract a sub-set of these data for inclusion in Guide A, Section 3. This paper reports the project process and outcome. Specifically, it describes the source of existing data, comments on the robustness of the underlying test procedures and presents a new approach to data classification and conflation
âIâd Rather Be Dead Than DisabledââThe Ableist Conflation and the Meanings of Disability
Despite being assailed for decades by disability activists and disability studies scholars spanning the humanities and social sciences, the medical model of disabilityâwhich conceptualizes disability as an individual tragedy or misfortune due to genetic or environmental insultâstill today structures many cases of patientâpractitioner communication. Synthesizing and recasting work done across critical disability studies and philosophy of disability, I argue that the reason the medical model of disability remains so gallingly entrenched is due to what I call the âableist conflationâ of disability with pain and suffering. In an effort to better equip healthcare practitioners and those invested in health communication to challenge disability stigma, discrimination, and oppression, I lay out the logic of the ableist conflation and interrogate examples of its use. I argue that insofar as the semiosis of pain and suffering is structured by the lived experience of unwelcome bodily transition or variation, experiences of pain inform the ableist conflation by preemptively tying such variability and its attendant disequilibrium to disability. I conclude by discussing how philosophy of disability and critical disability studies might better inform health communication concerning disability, offering a number of conceptual distinctions toward that end
Conflation: a new type of accelerated expansion
In the framework of scalar-tensor theories of gravity, we construct a new
kind of cosmological model that conflates inflation and ekpyrosis. During a
phase of conflation, the universe undergoes accelerated expansion, but with
crucial differences compared to ordinary inflation. In particular, the
potential energy is negative, which is of interest for supergravity and string
theory where both negative potentials and the required scalar-tensor couplings
are rather natural. A distinguishing feature of the model is that, for a large
parameter range, it does not significantly amplify adiabatic scalar and tensor
fluctuations, and in particular does not lead to eternal inflation and the
associated infinities. We also show how density fluctuations in accord with
current observations may be generated by adding a second scalar field to the
model. Conflation may be viewed as complementary to the recently proposed
anamorphic universe of Ijjas and Steinhardt.Comment: 22 pages, 6 figures, replaced with published versio
How to Combine Independent Data Sets for the Same Quantity
This paper describes a new mathematical method called conflation for consolidating data from independent experiments that measure the same physical quantity. Conflation is easy to calculate and visualize and minimizes the maximum loss in Shannon information in consolidating several independent distributions into a single distribution. A formal mathematical treatment of conflation has recently been published. For the benefit of experimenters wishing to use this technique, in this paper we derive the principal basic properties of conflation in the special case of normally distributed (Gaussian) data. Examples of applications to measurements of the fundamental physical constants and in high energy physics are presented, and the conflation operation is generalized to weighted conflation for cases in which the underlying experiments are not uniformly reliable. When different experiments are designed to measure the same unknown quantity, how can their results be consolidated in an unbiased and optimal way? Given data from experiments made at different times, in different locations, with different methodologies, and perhaps differing even in underlying theory, is there a straightforward, easily applied method for combining the results from all of the experiments into a single distribution? This paper describes a new mathematical method called conflation for consolidating data from independent experiments that measure the same physical quantity
Acronyms as an integral part of multiâword term recognition - A token of appreciation
Term conflation is the process of linking together different variants of the same term. In automatic term recognition approaches, all term variants should be aggregated into a single normalized term representative, which is associated with a single domainâspecific concept as a latent variable. In a previous study, we described FlexiTerm, an unsupervised method for recognition of multiâword terms from a domainâspecific corpus. It uses a range of methods to normalize three types of term variation â orthographic, morphological and syntactic variation. Acronyms, which represent a highly productive type of term variation, were not supported. In this study, we describe how the functionality of FlexiTerm has been extended to recognize acronyms and incorporate them into the term conflation process. The main contribution of this study is not acronym recognition per se, but rather its integration with other types of term variation into the term conflation process. We evaluated the effects of term conflation in the context of information retrieval as one of its most prominent applications. On average, relative recall increased by 32 percent points, whereas index compression factor increased by 7 percent points. Therefore, evidence suggests that integration of acronyms provides nonâtrivial improvement of term conflation
Further developments in the conflation of CFD and building simulation
To provide practitioners with the means to tackle problems related to poor indoor environments, building simulation and computational fluid dynamics can usefully be integrated within a single computational framework. This paper describes the outcomes from a research project sponsored by the European Commission, which furthered the CFD modelling aspects of the ESP-r system. The paper summarises the form of the CFD model and describes the method used to integrate the thermal and flow domains
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