Search results for "Receiver"

Feature selection using ROC curves on classification problems

2010

Feature Selection (FS) is one of the key stages in classification problems. This paper proposes the use of the area under Receiver Operator Characteristic curves to measure the individual importance of every input as well as a method to discover the variables that yield a statistically significant improvement in the discrimination power of the classification model.

2021

ObjectivesTo assess the ability to predict individual unfavourable future status and development in the 20m shuttle run test (20MSRT) during adolescence with machine learning (random forest (RF) classifier).MethodsData from a 2-year observational study (2013‒2015, 12.4±1.3 years, n=633, 50% girls), with 48 baseline characteristics (questionnaires (demographics, physical, psychological, social and lifestyle factors), objective measurements (anthropometrics, fitness characteristics, physical activity, body composition and academic scores)) were used to predict: (Task 1) unfavourable future 20MSRT status (identification of individuals in the lowest 20MSRT tertile after 2 years), and (Task 2) u…

Receiver-operating characteristic curves for somatic cell scores and California mastitis test in Valle del Belice dairy sheep.

2013

Using receiver-operating characteristic (ROC) curve methodology this study was designed to assess the diagnostic effectiveness of somatic cell count (SCC) and the California mastitis test (CMT) in Valle del Belice sheep, and to propose and evaluate threshold values for those tests that would optimally discriminate between healthy and infected udders. Milk samples (n = 1357) were collected from 684 sheep in four flocks. The prevalence of infection, as determined by positive bacterial culture was 0.36, 87.7% of which were minor and 12.3% major pathogens. Of the culture negative samples, 83.7% had an SCC < 500,000/mL and 97.4% had <1,000,000 cells/mL. When the associations between SC score (SC…

Accuracy in Detecting Artificial Root Resorption in Panoramic Radiography versus Tomosynthetic Panoramic Radiographs.

2019

The aim of this study was to compare the detection accuracy of panoramic radiography (PAN) and tomosynthetically reconstructed panoramic radiography (TPAN) for the detection of artificial external root resorption in a multiobserver approach.Thirty-six teeth in 5 dry human mandibles were prepared with artificial root resorption by means of diamond bur defects (0.8, 1.0, and 1.2 mm). The samples were exposed in a digital panoramic radiographic unit in a predetermined appropriate position using a wax layer (6.25 mm thickness) as soft tissue scatter equivalent and a water-filled plastic bottle to mimic the absorption of the cervical spine. This resulted in 5 panoramic radiographs and 5 tomosynt…

Evaluating a Two-Level vs. Three-Level Fall Risk Screening Algorithm for Predicting Falls Among Older Adults

2020

Background and Objectives: Falls account for the highest proportion of preventable injury among older adults. Thus, the United States' Centers for Disease Control and Prevention (CDC) developed the Stopping Elderly Accidents, Deaths, and Injuries (STEADI) algorithm to screen for fall risk. We referred to our STEADI algorithm adaptation as “Quick-STEADI” and compared the predictive abilities of the three-level (low, moderate, and high risk) and two-level (at-risk and not at-risk) Quick-STEADI algorithms. We additionally assessed the qualitative implementation of the Quick-STEADI algorithm in clinical settings. Research Design and Methods: We followed a prospective cohort (N = 200) of adults …

The Stroke Riskometer (TM) App: Validation of a data collection tool and stroke risk predictor

2014

Background The greatest potential to reduce the burden of stroke is by primary prevention of first-ever stroke, which constitutes three quarters of all stroke. In addition to population-wide prevention strategies (the ‘mass’ approach), the ‘high risk’ approach aims to identify individuals at risk of stroke and to modify their risk factors, and risk, accordingly. Current methods of assessing and modifying stroke risk are difficult to access and implement by the general population, amongst whom most future strokes will arise. To help reduce the burden of stroke on individuals and the population a new app, the Stroke Riskometer™, has been developed. We aim to explore the validity of the app fo…

Vasoactive peptide urotensin II in plasma is associated with cerebral vasospasm after aneurysmal subarachnoid hemorrhage and constitutes a potential …

2019

National audience; OBJECTIVECerebral vasospasm (VS) is a severe complication of aneurysmal subarachnoid hemorrhage (SAH). Urotensin II (UII) is a potent vasoactive peptide activating the urotensin (UT) receptor, potentially involved in brain vascular pathologies. The authors hypothesized that UII/UT system antagonism with the UT receptor antagonist/biased ligand urantide may be associated with post-SAH VS. The objectives of this study were 2-fold: 1) to leverage an experimental mouse model of SAH with VS in order to study the effect of urotensinergic system antagonism on neurological outcome, and 2) to investigate the association between plasma UII level and symptomatic VS after SAH in huma…

Increased serum miR-193a-5p during non-alcoholic fatty liver disease progression: Diagnostic and mechanistic relevance

2022

Background & Aims Serum microRNA (miRNA) levels are known to change in non-alcoholic fatty liver disease (NAFLD) and may serve as useful biomarkers. This study aimed to profile miRNAs comprehensively at all NAFLD stages. Methods We profiled 2,083 serum miRNAs in a discovery cohort (183 cases with NAFLD representing the complete NAFLD spectrum and 10 population controls). miRNA libraries generated by HTG EdgeSeq were sequenced by Illumina NextSeq. Selected serum miRNAs were profiled in 372 additional cases with NAFLD and 15 population controls by quantitative reverse transcriptase PCR. Results Levels of 275 miRNAs differed between cases and population controls. Fewer differences were seen wi…

In vitro perception of low-contrast features in digital, film, and digitized dental radiographs: A receiver operating characteristic analysis

2005

Objective To compare experimentally the image quality of charged-coupled device (CCD)-based digital, flatbed scanner digitized, and dental film radiographs. Study design High-contrast standardized radiographs of an aluminum step wedge containing boreholes were obtained on dental radiographic film (F) and a CCD receptor (D). Digitization (S) was done with a flatbed scanner. Each radiograph was separated into 23 single images, 18 of which showed a dark spot. Thirty observers indicated their confidence on the visibility of the spots for a receiver operating characteristic (ROC) analysis. Results Mean Az values (area beneath the ROC curves) differed significantly (P < .05), being highest for D …

On Obtaining Classification Confidence, Ranked Predictions and AUC with Tsetlin Machines

2020

Tsetlin machines (TMs) are a promising approach to machine learning that uses Tsetlin Automata to produce patterns in propositional logic, leading to binary (hard) classifications. In many applications, however, one needs to know the confidence of classifications, e.g. to facilitate risk management. In this paper, we propose a novel scheme for measuring TM confidence based on the logistic function, calculated from the propositional logic patterns that match the input. We then use this scheme to trade off precision against recall, producing area under receiver operating characteristic curves (AUC) for TMs. Empirically, using four real-world datasets, we show that AUC is a more sensitive meas…