100 research outputs found
Contextual classification of multispectral image data
There are no author-identified significant results in this report
Estimating a Service-Life Distribution Based on Production Counts and a Failure Database
Problem: A manufacturer wanted to compare the service-life distributions of two similar products. These concern product lifetimes after installation (not manufacture). For each product, there were available production counts and an imperfect database providing information on failing units. In the real case, these units were expensive repairable units warrantied against repairs. Failure (of interest here) was relatively rare and driven by a different mode/mechanism than ordinary repair events (not of interest here).
Approach: Data models for the service life based on a standard parametric lifetime distribution and a related limited failure population were developed. These models were used to develop expressions for the likelihood of the available data that properly accounts for information missing in the failure database.
Results: A Bayesian approach was employed to obtain estimates of model parameters (with associated uncertainty) in order to investigate characteristics of the service-life distribution. Custom software was developed and is included as Supplemental Material to this case study. One part of a responsible approach to the original case was a simulation experiment used to validate the correctness of the software and the behavior of the statistical methodology before using its results in the application, and an example of such an experiment is included here.
Because of confidentiality issues that prevent use of the original data, simulated data with characteristics like the manufacturer\u27s proprietary data are used to illustrate some aspects of our real analyses. We note also that, although this case focuses on rare and complete product failure, the statistical methodology provided is directly applicable to more standard warranty data problems involving typically much larger warranty databases where entries are warranty claims (often for repairs) rather than reports of complete failures
An Introduction to Statistical Issues and Methods in Metrology for Physical Science and Engineering
This article provides an overview of the interplay between statistics and measurement. Measurement quality affects inference from data collected and analyzed using statistical methods while appropriate data analysis quantifies the quality of measurements. This article brings material on statistics and measurement together in one place as a resource for practitioners. Both frequentist and Bayesian methods are discussed
An Exact Formula for the Average Run Length to False Alarm of the Generalized Shiryaev-Roberts Procedure for Change-Point Detection under Exponential Observations
We derive analytically an exact closed-form formula for the standard minimax
Average Run Length (ARL) to false alarm delivered by the Generalized
Shiryaev-Roberts (GSR) change-point detection procedure devised to detect a
shift in the baseline mean of a sequence of independent exponentially
distributed observations. Specifically, the formula is found through direct
solution of the respective integral (renewal) equation, and is a general result
in that the GSR procedure's headstart is not restricted to a bounded range, nor
is there a "ceiling" value for the detection threshold. Apart from the
theoretical significance (in change-point detection, exact closed-form
performance formulae are typically either difficult or impossible to get,
especially for the GSR procedure), the obtained formula is also useful to a
practitioner: in cases of practical interest, the formula is a function linear
in both the detection threshold and the headstart, and, therefore, the ARL to
false alarm of the GSR procedure can be easily computed.Comment: 9 pages; Accepted for publication in Proceedings of the 12-th
German-Polish Workshop on Stochastic Models, Statistics and Their
Application
An ounce of time, a pound of responsibilities and a ton of weight to lose: An autoethnographic journey of barriers, message adherence and the weight-loss process
This article uses an autoethnographic approach to determine how the intersectionality of identities affects message perceptions about weight loss from the lens of two doctoral students. This autoethnography links our personal experiences with the societal and cultural phenomena of obesity and weight loss, and the rhetoric of messages. We know there is a gap in public relations literature about autoethnography, health communication and intersectionality, and we hope to fill it. We also know health communicators seek more effective ways to reach an increasingly diverse audience; we hope to shed light on the issue. We know that many women want to lose weight and hope our narratives will resonate with them. Finally, we recognize autoethnographic skeptics exist in academia, and we hope our article provides insight into and understanding of the usefulness of autoethnographies in the field of public relations.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
Imagining the Lives of Others: Empathy in Public Relations
This paper asks how we might theorise empathy in public relations (PR) in the light of a widespread ‘turn’ towards emotion in the academy, as well as in popular discourse. Two distinct notions of empathy are explored: ‘true’empathy as discussed in intercultural communication, is driven by a human concern for the other in order to understand experiences, feelings and situations that may be different from our own; whereas ‘instrumental’ empathy, reflecting a self orientation, is said to characterise much neoliberal market discourse in which corporations are urged to understand their customers better. Thus, while empathy may seem highly desirable as a means to enter into dialogue with an organisation’s publics, particularly during times of social upheaval and crisis, it is important to pay attention to empathy in public relations discourses including whose goals are served by empathetic engagement; and the type(s) of empathy called upon within a PR context. A literature review identified a socio-cultural definition of empathy as ‘imaginary effort’. A review of the public relations literature, however, found that while empathy is considered an important principle and personal attribute, notions of empathy, with a few exceptions, are under-explored. Nonfunctionalist, socio-cultural research which examines the meanings that practitioners associate with empathy is distinctly lacking; therefore in order to gain further insight into empathy, two sources of data were explored. The analysis of a popular online practitioner blog showed that other-centred empathic skill is discursively framed as instrumental in achieving clients’ business objectives. The analysis of three empathy statements drawn from 12 in-depth interviews with practitioners revealed complex empathic discourse in practitioner-client relationships. While the findings are limited to illustrative analyses only, this paper challenges researchers to develop conceptualisations and perspectives of empathy as imaginary effort in public relations
Statistical Modeling of Single Target Cell Encapsulation
High throughput drop-on-demand systems for separation and encapsulation of individual target cells from heterogeneous mixtures of multiple cell types is an emerging method in biotechnology that has broad applications in tissue engineering and regenerative medicine, genomics, and cryobiology. However, cell encapsulation in droplets is a random process that is hard to control. Statistical models can provide an understanding of the underlying processes and estimation of the relevant parameters, and enable reliable and repeatable control over the encapsulation of cells in droplets during the isolation process with high confidence level. We have modeled and experimentally verified a microdroplet-based cell encapsulation process for various combinations of cell loading and target cell concentrations. Here, we explain theoretically and validate experimentally a model to isolate and pattern single target cells from heterogeneous mixtures without using complex peripheral systems.Wallace H. Coulter Foundation (Young Investigator in Bioengineering Award)National Institutes of Health (U.S.) (Grant R01AI081534)National Institutes of Health (U.S.) (Grant R21AI087107
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