survivor function

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Measurement Error for Age of Onset in Prevalent Cohort Studies

Measurement Error for Age of Onset in Prevalent Cohort Studies

we use the same strategy to generate length-biased survival data with measurement error in disease onset times as in Section 3.2. The “correct” likelihood is considered here in two scenarios: the variance of the measurement error ( φ = log σ ) is known or unknown. Figure 3 shows the estimated survivor functions based on the condi- tional and unconditional likelihood approaches which ignoring the measurement error and “correct” conditional and unconditional likelihood approaches based on (12) and (14). From this figure, we can find that the proposed “correct” likelihood approach adjusts the measurement error well and leads to better estimates of the survivor functions. Table 4 summarizes the empirical properties of the estimates based on the naive parametric condi- tional likelihood, the “correct” parametric conditional likelihood, the naive parametric unconditional likelihood, and the “correct” parametric unconditional likelihood. For the corrected likelihood we maximize (12) and (14) both with respect to ψ (i.e. when φ is treated as unknown) and with respect to θ when φ is fixed at the true value. Whether the variance of error ( ) φ is known or unknown, the “correct” likelihood approach reduces the bias of estimates, and the resulting empirical coverage probabilities are all within the acceptable range. These simulations therefore provide empirical support to the claim that the “correct” likelihood approach adjusts for the measurement error and yields consistent estimators. Notable is the only modest increase in the empirical or average standard errors of parameter estimates when the variance of the measurement error distribution is es- timated, especially for the shape parameter κ . The “correct” likelihood approach also provides a good estima- tor of φ , and the empirical bias of estimator for φ is small at 0.03 with standard error 0.27 for the conditional analysis and 0.01 with standard error 0.11 for the unconditional analysis, when φ = log1 0 = , for example.
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THE IMPACT OF LOCATION BASED ATTACKS ON GEOGRAPHICAL ROUTING PROTOCOLS

THE IMPACT OF LOCATION BASED ATTACKS ON GEOGRAPHICAL ROUTING PROTOCOLS

Survival analysis, also known as time-to-event analysis, focuses on modeling waiting times until events of interest occur. This paper proposes statistical flowgraph models (SFGMs) as a suitable decision support tool for survival analysis in power systems. SFGMs are useful for modeling time-to-event data that result from a stochastic process. Analysis from the flowgraph model gives an entire waiting time distribution as well as cumulative distribution function, survivor function and hazard function for any total or partial waiting time. The importance of survival analysis in power system is demonstrated when our power supply is disrupted. Two examples illustrated in this paper demonstrate with clarity, the effectiveness of SFGMs to the survival analysis in power systems. One of the advantages of SFGMs is to reduce the multistate models into an equivalent binary-state model. Based on this study, the authors suggest that the use of SFGMs will help decision makers to identify weak points in the system in order to control system conditions.
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Cross-sectional and longitudinal approaches in a survival mixture model

Cross-sectional and longitudinal approaches in a survival mixture model

for the parameters defining the susceptible survivor function perform better at an earlier time and smaller gap between the first and second visit. The reverse however is true for the estimators of the unknown parameters defining the proportion of long term survivors in the data. Nonetheless, the combined results from the longitudinal approach are still desirable since the bias in most cases is small and the level of precision is evidently better in the longitudinal analysis which is further justified by the smaller-than-unity values of the relative efficiency measures.

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Power-Law Adjusted Failure-Time Models

Power-Law Adjusted Failure-Time Models

Fig.3 shows the MLES of the hazard rate for (clockwise from upper left) the power-law adjusted Weibull, log-gamma, lognormal and Pareto distributions. While these plots may appear very different to the non-parametric estimate of the hazard function (Fig.2) at the upper end, it should be noted that the upper part of the non-parametric estimate is not very precise, since in the dataset there are only two observations greater than 6000 (with values 6065 and 9701). Fig.4 shows the fitted power-law adjusted Pareto hazard rate function superimposed on the non-parametric estimate on the range 0 to 6000 cycles. Also Fig.5 shows the Kaplan-Meier estimate of the survivor function and the fitted survivor function for the power-law adjusted Pareto distribution. Both plots suggest a good fit.
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Determination of the most appropriate method for extrapolating overall survival data from a placebo-controlled clinical trial of lenvatinib for progressive, radioiodine-refractory differentiated thyroid cancer

Determination of the most appropriate method for extrapolating overall survival data from a placebo-controlled clinical trial of lenvatinib for progressive, radioiodine-refractory differentiated thyroid cancer

In order to fully capture the benefits of a therapy, it is often necessary to extrapolate survival data to a sufficient time point. The use of a transparent, systematic approach with an a priori selection process is required to facilitate the choice of an extrapolation method while reducing the risk of bias. Although it is tempting to present an extrapolation method that demonstrates the greatest marginal benefits, an appropri- ate approach should be conservative and fulfill the selection criteria. For the extrapolation of the RPSFT-adjusted OS data in SELECT, a piecewise model was considered the optimal, where the KM survivor function was used for the period of the trial data and the extrapolated tail was modeled using an Exponential distribution. The results presented here should not be considered definitive and should be used alongside expert clinical opinion to inform a final decision; nonetheless, they offer a valuable insight into extrapolation approaches for future comparative analyses.
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Extrapolating survival from randomised trials using external data : a review of methods

Extrapolating survival from randomised trials using external data : a review of methods

The long-term survivor function for the external data source S C ð t Þ may be estimated from national administrative data on population survival, disease registries, cohort studies, or elicited expert belief. Typical life-tables published by national statistics authorities provide age, sex, country, year, and cause-specific annual survival probabilities, which can be used to estimate lifetime survival for the gen- eral population. External data may also consist of cohorts of patients who are similar to the patients of interest. This could include national or regional reg- istries (such as cancer registries), or hospital-based cohorts including all patients with a particular condi- tion or receiving a particular treatment, from a partic- ular period of time. There may even be data from randomized trials in a similar population with a lon- ger follow-up. The advantages of registry or cohort data compared to unselected national population data are that the patient population may be more rep- resentative of the target population, and relevant covariates are more likely to be recorded. However, they may not necessarily have follow-up times cover- ing the whole lifetimes of all participants.
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Survivor Derivatives: A Consistent Pricing Framework

Survivor Derivatives: A Consistent Pricing Framework

These three hedging strategies fix the commitments of the pension fund, either for the entire period of survivorship or for all but the first 5 years, and this means that the fund would have no exposure to any financial benefits from decreasing survivorship during the hedged periods. These benefits could, however, be obtained by our fourth hedging strategy, namely, a position in a 5-year payer swaption. Again, the fund would accept survivor risk for the first 5 years but would then have the right, but not the obligation, to enter a pay-fixed swap on pre-agreed terms. Using the same beta parameters as above, the annual volatility of the forward contract is 4.36 percent and the premium for an at-the-money forward swaption is 3.35 percent. Applying the swaption formula, the pension fund would pay an option premium of approximately $32 million to gain the right but not the obligation to fix the payments at a π rate of 15.07 percent thereafter. If survivorship declines, the fund will not exercise the option and will have lost merely the $32 million swaption premium but then reaps the benefit of the decline in survivorship.
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Building survivor activism: An organisational view

Building survivor activism: An organisational view

after each event; when a group is strong, individual feedback forms are often not wanted. Instead, creating a climate of trust and building confidence means that survivor activists will express themselves when they need to. And this works two ways in a mutually respectful relationship. All of this information is collated and fed back into the development of the projects. Unfortunately, we have not yet had the resources to carry out any clinical evaluations as a result of our projects. Certainly, for many of the survivor activists, although anecdotal evidence, they report that their involvement has led to an increase in their skills and confidence, and many have since secured employment including in engineering, academia, as interpreters, writers and authors, and as well as organisations like Freedom from Torture. Additionally, Freedom from Torture carried out a survivor-led six month study in 2016 involving over 100 clients to explore the meaning of rehabilitation to survivors. Some clients reported that feeling empowered to speak out about what had happened to them, and advocating for other survivors with decision makers or to public audiences, was a key part of rehabilitation. “They said that using their voice empowers them and helps restore their confidence. This is especially important for people who previously felt unable to use their voice to speak out in public.” (Haoussou, 2018 p. 69)
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Is the Traditional Banking Model a Survivor?

Is the Traditional Banking Model a Survivor?

The concept of survivorship was first introduced by Stigler (1958) and we adapt it for our own unique purposes here. We label a bank to be a survivor if it did not fail, and was not acquired by another bank, during our 1997 to 2012 sample period. In other words, we recognize that non-survival can occur not just for financial reasons (for example, a bank becomes insolvent or illiquid), but also for strategic reasons (for example, a bank has a bad business model and/or it executes its business model poorly, and as a result disappears in the market for corporate control). We measure the degree to which surviving and non-surviving banks were using traditional business models based on four hallmark characteristics of traditional commercial banking: Relationship lending, core deposit funding, revenues generated from traditional banking services, and intensive use of bank branches. We focus our analysis on banks with assets between $500 million and $10 billion, that is, banks that are large enough to capture the bulk of the scale economies available in the traditional business model, but still too small to fully exploit the production efficiencies available in a more modern transactions-type business model.
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Non-survivor patients with malignant middle cerebral artery infarction showed persistently high serum malondialdehyde levels

Non-survivor patients with malignant middle cerebral artery infarction showed persistently high serum malondialdehyde levels

We believed that those higher concentrations of serum malondialdehyde during the first week of MMCAI in non-survivor patients reflects a higher ROS production and lipid peroxidation in comparison to survivor pa- tients, and the use of antioxidant agents could be a new therapeutic to explore in MMCAI patients. The adminis- tration of melatonin in animal models of ischemic stroke has been associated with a reduction of oxidation [18–22], specifically a reduction of malondialdehyde levels [21, 22], and even an increase of survival. In patients with ischemic stroke, the oral administration of different antioxidant vi- tamins (B2, B6, B12, C, E) during the first 14 days of stroke has been associated with lower plasma levels of malondial- dehyde [23–25]. Thus, although we recognize that our study has the limitation that other oxidant state com- pounds were not reported, we think that all those findings could open the interest for study in patients with ischemic strike the oxidative stress and the potential role of antioxi- dant agents in your treatment.
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Total antioxidant capacity is associated with mortality of patients with severe traumatic brain injury

Total antioxidant capacity is associated with mortality of patients with severe traumatic brain injury

Background: Previously, circulating total antioxidant capacity (TAC) in traumatic brain injury (TBI) patients has been scarcely studied and only in studies of small sample size (lower than 55 TBI patients). In one study were found higher serum TAC in non-survivor than in survivor TBI patients; however, an association between circulating TAC and mortality in patients with TBI has not been previously reported. Thus, the objective of this study was to determine whether there is an association between circulating TAC, peroxidation state and mortality in patients with severe TBI.

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Tension Analysis in Survivor Interviews: A Computational Approach

Tension Analysis in Survivor Interviews: A Computational Approach

So it is necessary to have rules that can disambiguate di ff erent markers as well. Moreover, we trained our model for recognizing emotion from text using Twitter data. We would achieve [r]

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Power Efficient Survivor Memory Architecture for Viterbi Decoder

Power Efficient Survivor Memory Architecture for Viterbi Decoder

In Fig. 1 (a), the trellis states are denoted as (S1, S0) = 00, 01, 10, 11. Each branch is a survivor path transition determined by the decision bits from the ACSU. The black branch is the final converged path, which can be utilized for decoding. Fig. 1 (b) shows the operation of the register in the RE scheme, and Fig. 1 (c) is the TF technique. Both 2 schemes exchange the contents of the register like the survivor path transition. In this example, the initial decoding bit is 0, and the initial start state is state 2. After 10 iteration, the register contents of 2 schemes all converges.
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FROM MOUNTAINS TO MOLEHILLS: EPISODES FROM THE LIFE OF A SURVIVOR

FROM MOUNTAINS TO MOLEHILLS: EPISODES FROM THE LIFE OF A SURVIVOR

autobiography. I read feminist theory on autobiography; discussions of women's writing and 'the' canon and incest survivor autobiographies. Much of what I read illuminated my experienc[r]

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FROM MOUNTAINS TO MOLEHILLS: EPISODES FROM THE LIFE OF SURVIVOR

FROM MOUNTAINS TO MOLEHILLS: EPISODES FROM THE LIFE OF SURVIVOR

Trisha stayed with me. I wrote up my death notice for Grandma. Our family is very big on personal notices. I walked around her garden endlessly. I listened to plans for the funeral tha[r]

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The Construction of Self in an Adult Survivor of Childhood Sexual Abuse

The Construction of Self in an Adult Survivor of Childhood Sexual Abuse

Construction of Self in an Adult Survivor of Childhood Sexual Abuse: Thematic Structure. Central Construct: Self[r]

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Sex Trafficking Survivor, Pro-Life Advocate

Sex Trafficking Survivor, Pro-Life Advocate

I would like to express my sincere gratitude to Dr. Donna Hughes for the opportunity and guidance through this report, as well as Lisa Thompson, whose technical suggestions added clarity to the work. I’d also like to thank Anthy Pallas and Marilyn Birnie for their heroic actions that made this possible. Rebecca Kiessling for her assistance with this project. I’m grateful for all who are cited in this piece. Dignity thanks the following people for their time and expertise in reviewing and editing: Lisa Thompson, vice president for education and outreach, National Center on Sexual Exploitation, Tanya Street, human trafficking survivor leader and founder of Identifiable Me, and Lily Lachapelle, University of Rhode Island double major in psychology and gender and women’s studies with a minor in Arabic.
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Effects of Intravascular Laser Irradiation of Blood
on Cognitive Function in a Stroke Survivor with
Hyperhomocysteinemia: Dual Recuperations in
Thalamus and Serum Homocysteine

Effects of Intravascular Laser Irradiation of Blood on Cognitive Function in a Stroke Survivor with Hyperhomocysteinemia: Dual Recuperations in Thalamus and Serum Homocysteine

tracts consisting of the fornix, mammillothalamic tract, cingulum bundle, and anterior thalamic nuclei [27]. In addition, three pre- frontal-subcortical circuits are involved in Behavioral and cognitive alterations, e.g. the dorsolateral prefrontal circuits, the orbitofron- tal circuits and the anterior cingulate circuits [28]. An ischemic stroke lesion related to post-stroke cognitive impairment often perturb the prefrontal-subcortical circuits including the bundles of white matter (corona radiate or centrum semiovale) [29], leading to executive deficits associated with prefrontal hypoperfusion [30]. Since disturbances in both local and global networks in the brain have been associated with deficits in cognitive function, therefore, disrupted or lately repaired neural network activity may provide valuable observation of a therapeutic intervention.
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Exited Prostitution Survivor Policy Platform

Exited Prostitution Survivor Policy Platform

Beth Jacobs is a survivor of child sex trafficking who earned a degree in social work, leading to over 15 years helping victims of sex trafficking and sexual exploitation become survivors and leaders. She spearheaded the Offenders’ Prostitution Program (John school) in St. Paul Minnesota; started Willow Way in Tucson, Arizona, to help sexually exploited people; and collaborated with county courts and police in Arizona to create Project Raise, as an alternative to jail for prostituted and sex trafficked people. At the national and state levels, she has advocated for more effective legislation, especially to update laws against human trafficking. She is a National Survivor Network policy champion and has worked for the Alliance to End Slavery and Trafficking (ATEST). Jacobs is a field trainer for Truckers Against Trafficking as well as a field instructor for social work students at Winona State University and the Alfred Adler Institute. Jacobs was a speaker at the first International Meeting for Human Trafficking Survivors held in Cali, Columbia in 2014.
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Exploring survivor perceptions of pre eclampsia and eclampsia in Nigeria through the health belief model

Exploring survivor perceptions of pre eclampsia and eclampsia in Nigeria through the health belief model

Exploring survivor perceptions of pre eclampsia and eclampsia in Nigeria through the health belief model RESEARCH ARTICLE Open Access Exploring survivor perceptions of pre eclampsia and eclampsia in N[.]

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